La Mesa City Council
June 14, 2022

56 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 57 Current Status of 2 the Urban Forest
Table 15. Age Distribution of La Mesa’s Urban Forest Based on Trees’ Diameter at Standard Height DSH (inches) Age Category* % of All City Trees City Street Trees (%) City Park Trees (%) 0–6 Immature 26% 26% 26%
7–18 Young 65% 68% 60%
19–24 Middle-aged 5% 4% 10%
25–30+ Mature 3% 2% 4%
Note: DSH = diameter at standard height. | * Source: Richards 1983.

Table 16. Tree Inventory Health Categories
Dead Tree is no longer viable and should be removed
Poor Tree exhibits significant deficiencies in health and canopy structure Fair Tree exhibits minor deficiencies in health and canopy structure Good Tree exhibits normal health and canopy structure
Table 17. Health Composition
of All City-Maintained Trees
Number
of Trees
% of
Trees
Dead 63 1%
Poor 256 2.5%
Fair 1072 10.5%
Good 8769 86%
Table 18. Health Composition of Park Trees and Street Trees by Age Park Trees Street Trees
Immature* Young Middle-aged Mature Immature Young Middle-aged Mature Dead 1% 1% 1% 1% 0% 1% 0% 1%
Poor 4% 2% 3% 1% 3% 2% 1% 1%
Fair 13% 8% 7% 8% 12% 11% 11% 13%
Good 83% 89% 89% 90% 84% 86% 88% 85%
determine the structural integrity of the trees.

Arborists are not able to determine all the
causal factors contributing to tree health while
conducting an inventory in the field, and more
sophisticated diagnostic studies would be
recommended if warranted.

La Mesa fosters a healthy, publicly managed
tree inventory, with 96.5% of trees rated as
good or fair (Table 17). Understanding the
health of particular age classes (Richards
1983) could also help identify if, trees of a
certain age are experiencing poor health due
to maintenance factors. When separating
the trees by age class and location (street
tree versus park tree), Table 18 shows that
between 96% and 98% of park trees and
between 96% and 99% of street trees were
rated as good or fair, regardless of their age
class. Based on the data presented in Table
18, age does not appear to be a factor in the
health composition of La Mesa’s urban forest.

Although the data reflects a positive health
rating of the City’s tree inventory, the
distribution of trees rated as good appears
to be higher than what is usual for municipal
tree inventories in an urban setting. It will
be important for the City to understand the
methods used by the inventory arborists to
assign health ratings to ensure a consistent
application of health ratings that align
with International Society of Arboriculture
standards. Established definitions and
practices for health ratings will help promote
effective management decisions to maintain
tree health as well as provide a clear baseline
for when trees are performing well or are in
decline.

2.5.4 Relative Performance Index
Another component of the health of the
City’s urban forest is to look at the relative
performance index (RPI) of tree species
(USFS 2020). RPI is a numerical value, which
is calculated by dividing the percentage of a
tree species rated as having a good health
condition by the percentage of the entire
tree population rated as having good health
condition. Trees with RPI values higher than
1 are performing better than the average city
tree, and those with an RPI value less than
1 are performing below average. Table 19
provides the RPI values for La Mesa’s 10 most
common tree species.

The RPI values show that 9 of the 10 most
Park trees in La Mesa, CA common species are performing at or better

58 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 59 Current Status of 2 the Urban Forest
Table 20. Top 10 Importance Values of Tree Species in La Mesa Scientific Name Common Name % of population % Leaf Area Importance values Syagrus romanzoffianum Queen palm 12.9 7.5 20.3
Washingtonia robusta Mexican fan palm 9.9 9.1 19.0
Eucalyptus cladocalyx Sugar gum 2.8 9.3 12.2
Eucalyptus camaldulensis River red gum 2.8 6 8.9
Liquidambar styraciflua Sweetgum 4.4 4 8.4
Lagerstroemia indica Crape myrtle 5.5 1.3 6.7
Platanus × hispanica London plane 2.2 4.3 6.5
Pinus canariensis Canary Island pine 3.3 3.2 6.5
Pinus halepensis Aleppo pine 2.7 3.1 5.8
Jacaranda mimosifolia Jacaranda 2.6 2.6 5.2
Syagrus romanzoffianum, Queen palm
Table 19. Relative Performance Index Values for the Top 10 Most Common Species in La Mesa’s Urban Forest Rank Scientific Name Common Name No. of Trees
% of trees rated in
good health
Relative Performance
Index (RPI)
All Trees 8,769 86% 1.000
1 Syagrus romanzoffianum Queen palm 1,307 92% 1.070
2 Washingtonia robusta Mexican fan palm 1,004 97% 1.128 3 Lagerstroemia indica Crape myrtle 543 96% 1.116
4 Liquidambar styraciflua Sweetgum 441 89% 1.035
5 Pinus canariensis Canary Island pine 333 93% 1.081
6 Eucalyptus camaldulensis River red gum 289 79% 0.919
7 Eucalyptus cladocalyx Sugar gum 288 92% 1.070
8 Pinus halepensis Aleppo pine 274 90% 1.047
9 Jacaranda mimosifolia Jacaranda 266 92% 1.070
10 Afrocarpus gracilior Fern pine 260 86% 1.000
Pinus halepensis, Aleppo pine

60 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 61 Current Status of 2 the Urban Forest

LARGE TREES
VS. SMALL TREES

THE BENEFITS OF
OXYGEN
CARBON

REALEASED INTO

ATMOSPHERE
OXYGEN

RELEASED INTO

THE ENVIRONMENT
CARBON

CAPTURED BY
TREES

5.5X MORE

STRUCTURAL
VALUE
4XMORE
CARBON
SEQUESTERED 4X GREATER

ENVIRONMENTAL
BENEFIT VALUE 5XMORE

STORMWATER
AVOIDANCE 6XMORE
SHADE
PROVIDED 7X MORE
CARBON

STORAGE
Large trees provide more benefits than small trees:
than the average city tree (Table 20). The
only species with a value lower than 1 is the
river red gum (Eucalyptus camaldulensis),
which has an RPI value of 0.919 that is close
to approaching the City average. As noted in
the discussion on health composition, further
information is needed on the assignment of
health ratings by the inventory arborists to
make definitive determinations as to what the
RPI is for the City inventory.

2.5.5 Importance Value
The importance value of a tree species is
another way to understand the dynamics
of how individual tree species impact La
Mesa’s urban forest. The importance value,
a tool designed by iTree-Eco, considers the
percentage of the species in the population
of City-owned trees and its corresponding
percentage of leaf area. These two percentages
are added together to determine the species’
importance of a City-managed tree to the
total urban forest. Table 20 shows the top 10
importance values of tree species in the La
Mesa tree inventory.

The trees with the highest importance values
include queen palm, Mexican fan palm,
and sugar gum (Eucalyptus cladocalyx). It is
expected that the two palm species have the
two highest importance values, 20.3 and 19.0,
respectively, given that these trees
make up 23% of La Mesa’s urban forest.

However, queen palms make up 12.9% of
the population but only 7.5% of the leaf area,
demonstrating that these palms species
provide a lower quantity of leaf area per tree in
comparison to other species in the inventory.

For example, the sugar gum makes up only

2.8% of the population but contributes 9.3%
of the inventory leaf area, for the third highest
importance value of 12.2. Similarly, river red
gum trees make up 2.8% of the population but
6% of the City’s leaf area and have the fourth
highest importance value of 8.9.

A high importance value does not inherently
mean it should be prioritized for tree planting
efforts, as is the case with Eucalyptus spp.

Research conducted by McBride and Lacan
(2018) suggest that Eucalyptus spp. trees
may have a difficult time adapting to future
warming trends that are predicted for
California. While both the river red gum and
sugar gum are contributing great benefits
to the urban forest, their ability to adapt to
changing climate conditions may warrant
substituting different large stature, climate
adapted trees on future planting plans.

2.6 Pest Management
Ensuring that trees are frequently monitored
for pests and diseases is an important
component of any pest management program.

The species composition of La Mesa’s tree
inventory is susceptible to several invasive
pests and pathogens that have been detected
in San Diego County by the California
Department of Food and Agriculture and
U.S. Department of Agriculture Animal Plant
Health Inspection Service, Plant Protection
and Quarantine Division (USDA APHIS PPQ).

Early detections of plant health problems
will provide the City with the best chances to
Figure 8: Benefits of large vs. small trees
A proactive approach to
pest management can help limit
the impact of regional pest threats
like palm weevils, goldspotted oak
borers, invasive shothole borer, and
Asian citrus psyllid.

The environmental benefits of a sample selection of
large, medium and small stature trees species were
analyzed to determine how their environmental
benefits compare:

62 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 63 Current Status of 2 the Urban Forest
Table 21. Invasive Pests and Pathogens that Threaten La Mesa’s Urban Forest Invasive Pests and
Pathogens that
Threaten La Mesa’s
Urban Forest
Scientific
Name Important Host Species Signs & Symptoms Management Actions Resources Photo Palm weevil Rhynochophorus spp. •Canary Island date palm (Phoenix canariensis)
•Dieback of the new growth
•Tunnels at trunk bases
•Sap ooze from tunnel holes
•Frass (insect excrement)
•Trunk and or crown failure.
•Regular scouting
•Send suspected individuals to the Entomology Diagnostic Lab at the San Diego County Agriculture Commissioner’s Office for identification. •Systemic insecticide programs and/or biological control of beetles involving parasitic flies may be recommended depending on the severity of the infestation. •Red palm weevil: https://cisr.ucr.edu/invasive-species/ red-palm-weevil
•South American palm weevil: https://biocontrol.ucr.
edu/ south-american-palm-weevil
Goldspotted Oak Borer Agrilus auroguttatus •California black oak, (Quercus agrifolia), •Coast live oak (Quercus agrifolia),
•Canyon live oak (Q. chrysolepis),
•Crown thinning
•Exit holes
•Bark staining
•Larva feeding galleries
•Regular scouting
•Send suspected individuals to the Entomology Diagnostic Lab at the San Diego County Agriculture Commissioner’s Office for identification. •Remove infested trees
•Cover removed, infested material with plastic to solarize wood and prevent adult emergence, as juveniles can live in dead wood until emergence.
•Replace removed trees with non-host species such as holly oak (Quercus ilex), cork oak (Quercus suber), or nonoaks.
•UC IPM: http://ipm.ucanr.edu/PMG/PESTNOTES/
pn74163.html
•UC Riverside Center for Invasive Species Research:
https://cisr.ucr.edu/invasive-species/goldspotted-oak-borer Invasive Shothole Borer and
Fusarium Dieback
Euwallacea spp. and
Fusarium spp.
•London plane (Platanus × hispanica)
•Box elder (Acer negundo),
•Oaks (Quercus spp.)
•Cottonwoods (Populus spp.)
•Willows (Salix spp.)
•Many other species
•Bark staining
•Gumming
•White powder on tree trunks
•Insect frass
•Regular scouting
•Use the Detection & Management Assessment Tool to gauge appropriate management decisions. •Send suspected individuals to the Entomology Diagnostic Lab at the San Diego County Agriculture Commissioner’s Office for identification. •Monitoring, chemical injections, and/or tree removal may be required. •For a complete host range, visit https://ucanr.edu/sites/ pshb/pest-overview/ishb-reproductive-hosts/
•ISHB Detection & Management Assessment Tool:
https://ucanr.co1.qualtrics.com/
jfe/form/SV_bIuyTZY7hkqiqod
Asian Citrus Psyllid and
Huanlongbing
Diaphorina citri and
Candidatus Liberibacter
asiaticus
•All citrus species
•Curry leaf (Murraya)
•Visible psyllids or waxy psyllid droppings
•Lopsided, bitter, hard fruit
•Fruit that remains green even when ripe
•Blotchy yellow and green leaves
•Yellow shoots
•Twig dieback
•Stunted, sparsely foliated trees that may bloom off season •All citrus species are currently under quarantine and cannot be transported across county lines. •Inform backyard citrus growers of the disease and pest risk. •UCANR Management Guidelines: https://ucanr.edu/
sites/ACP/Grower_Options/Grower_Management/Monitoring_15/ •UC IPM: http://ipm.ucanr.edu/PMG/
PESTNOTES/pn74155.html

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Table 22. Tree Species Planted in San Diego that Are Also Planted in La Mesa Scientific Name Common Name Scientific Name Common Name Acacia baileyana Bailey acacia Archontophoenix cunninghamiana King palm Acacia decurrens Green wattle Bauhinia blakeana Hong Kong orchid tree Acacia longifolia Sydney golden wattle Bauhinia variegata Purple orchid tree Acacia melanoxylon Black acacia Betula pendula European white birch Acacia salicina Willow acacia Brachychiton acerifolius Australian flame tree Acacia stenophylla Shoestring acacia Brachychiton populneus Bottle tree Acca sellowiana Pineapple guava Brahea armata Mexican blue palm Acer negundo Box elder Brahea edulis Guadalupe palm
Acer palmatum Japanese maple Butia capitata Pindo palm
Afrocarpus gracilior Fern pine Caesalpinia spinosa Bird of paradise Agonis flexuosa Peppermint tree Carya illinoinensis Pecan Ailanthus altissima Tree of heaven Caryota urens Fishtail wine palm Albizia julibrissin Silk tree Cassia leptophylla Golden wonder senna Alnus rhombifolia White alder Casuarina cunninghamiana River she-oak Araucaria columnaris Star pine Cedrus atlantica “Glauca” Cedar blue atlas Araucaria heterophylla Norfolk island pine Cedrus deodara Deodar cedar Arbutus “Marina” Marina madrone Ceratonia siliqua Carob Arbutus unedo Strawberry tree Cercis canadensis Eastern redbud sustain a healthy urban forest for the future.

Table 21 presents important invasive
pests and pathogens, management
recommendations, and resources to use in
the case of a plant health issue. These invasive
species have been recently introduced to
Southern California and are typically more
aggressive because they do not have natural
predators to keep their populations in check.

2.7 Recommended Species
Climate change is likely to cause substantial
negative impacts on commonly planted
street tree species in California (McBride and
Lacan 2018). Over the past century, average
maximum temperatures in California have
increased between 1.6°F to 2.5°F, and these
temperatures are expected to continue to rise
over the coming years (CDWR 2015.). Though
Southern California cities are predicted to
receive comparable levels of precipitation as
it does currently, rainfall is expected to occur
in less frequent, more severe events. These
precipitation events will result in the potential
for increased drought conditions. As such,
finding additional irrigation water or funding
sources for irrigation infrastructure as cities
become warmer and drier is likely to increase
in difficulty (McBride and Lacan 2018).

The City will need to examine its street tree
palette to understand whether it is prepared
for these predicted weather and climate
changes. Recent research by McBride and
Lacan (2018) provides helpful findings that
can guide the City as it plans for its hotter,
dryer future. The study selected 16 cities to
represent 16 different climate and weather
conditions throughout California. It then
identified a study city with a cooler climate to
one with a climate that represents what the
cooler study city is predicted to experience
over the next 100 years. The city-managed
tree inventory of each city was compared to
understand if there were differences between
the street tree species represented in each
city.

San Diego was identified as a cooler study
city, and it was compared to Santa Ana. Of San
Diego’s 25 most common street tree species,
none were absent from Santa Ana. Based
on the study’s findings, many of the trees
currently planted in San Diego will likely be
adapted to future climate conditions, and its
inventory can provide a baseline of appropriate
species for La Mesa. Table 22 shows the list of
species that are currently planted in both San
Diego and La Mesa. Of La Mesa’s 230 inventory
species, 201 of them are also planted in San
Diego.

The comparison with the San Diego inventory
is just one aspect of determining appropriate
tree species to plant in La Mesa. Another
component of developing a recommended
species list is the Water Use Classification of
Landscape Species (WUCOLS) rating, which
shows the level of water the species needs
to thrive. Prioritizing tree species that are
classified as very low or low water use trees will
help to ensure trees are adapted to predicted
drought conditions, while still allowing for a
Of La Mesa’s 230 species, 201 are planted in San Diego.

Research shows these species are likely to exist
under future climate conditions
Ceratonia siliqua, Carob

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Table 22. Tree Species Planted in San Diego that Are Also Planted in La Mesa, continued.

Scientific Name Common Name Scientific Name Common Name Cercis occidentalis Western redbud Dodonaea viscosa Dragon tree Chamaerops humilis Mediterranean fan palm Dodonaea viscosa “Purpurea” Hopseed bush Chilopsis linearis Desert willow Dracaena draco Dragon tree Chitalpa tashkentensis Chitalpa Dypsis decaryi Triangle palm Chitalpa tashkentensis “Pink Dawn” Pink Dawn chitalpa Elaeocarpus decipiens Japanese blueberry tree Cinnamomum camphora Camphor Eriobotrya deflexa Bronze loquat Citrus limon Lemon Eriobotrya japonica Edible loquat
Citrus reticulata Tangerine Erythrina caffra Kaffirbroom coral tree Citrus sinensis Orange Erythrina coralloides Naked coral tree Corymbia citriodora Lemon-scented gum Eucalyptus camaldulensis Red gum Corymbia ficifolia Red flowering gum Eucalyptus cinerea Ash gum Corymbia maculata Spotted gum Eucalyptus cladocalyx Sugar gum Cotinus coggygria Smoke tree Eucalyptus globulus Blue gum Cupaniopsis anacardioides Carrotwood Eucalyptus leucoxylon “Rosea” Red-flowering gum Cupressocyparis x leylandii Leyland cypress Eucalyptus nicholii Nichol’s willow leafed peppermint Cupressus sempervirens Italian cypress Eucalyptus polyanthemos Silver dollar gum Cycas revoluta Sago palm Eucalyptus robusta Swamp mahogany Cycas thouarsii Madagascar cycad Eucalyptus rudis Desert gum Table 22. Tree Species Planted in San Diego that Are Also Planted in La Mesa, continued.

Scientific Name Common Name Scientific Name Common Name Eucalyptus sideroxylon Red ironbark Juglans regia English walnut Euphorbia cotinifolia Caribbean copper tree Juniperus chinensis Chinese juniper Ficus benjamina Weeping fig Juniperus chinensis “Columnaris” Chinese blue column juniper Ficus carica Edible fig Juniperus chinensis “Torulosa” Hollywood juniper Ficus elastica Rubber tree Koelreuteria bipinnata Chinese flame tree Ficus macrophylla Moreton Bay fig Koelreuteria paniculata Goldenrain tree Ficus rubiginosa Rusty leaf fig Lagerstroemia indica Crape myrtle Fraxinus uhdei Shamel ash Lagerstroemia indica “Muskogee” Muskogee crape myrtle Fraxinus velutina Arizona ash Lagerstroemia indica “Tuscarora” Tuscarora crape myrtle Fraxinus velutina “Modesto” Modesto ash Laurus nobilis Sweet bay Geijera parviflora Silk oak Ligustrum japonicum Japanese privet Ginkgo biloba Gingko Ligustrum lucidum Glossy privet
Grevillea robusta Silk oak Liquidambar styraciflua American sweet gum Handroanthus heterophylla Pink trumpet tree Liquidambar styraciflua “Rotundiloba” Round-leafed sweetgum Harpephyllum caffrum Kaffir plum Livistona chinensis Chinese fountain palm Hesperocyparis forbesii Tecate cypress Livistona decipiens Weeping fountain palm Hymenosporum flavum Sweetshade Lophostemon confertus Brisbane box Jacaranda mimosifolia Jacaranda Macadamia integrifolia Smooth-shell macadamia Citrus sinensis, Orange Liquidambar styraciflua, American sweet gum

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Table 22. Tree Species Planted in San Diego that Are Also Planted in La Mesa, continued.

Scientific Name Common Name Scientific Name Common Name Magnolia champaca Champaca Phoenix roebelenii Pygmy date palm Magnolia grandiflora Southern magnolia Phoenix rupicola Cliff date palm Malus domestica Common apple Photinia X fraseri Fraser’s photinia Maytenus boaria Mayten tree Pinus brutia Calarian pine
Melaleuca armillaris Drooping melaleuca Pinus canariensis Canary island pine Melaleuca linariifolia Flaxleaf paperbark Pinus contorta Lodgepole pine Melaleuca nesophila Pink melaleuca Pinus eldarica Cajeput tree Melaleuca quinquenervia Cajeput tree Pinus halepensis Chinaberry Melia azedarach Chinaberry Pinus pinea Italian stone pine Metrosideros excelsus New Zealand Christmas tree Pinus radiata Monterey pine Morus alba White mulberry Pinus thunbergiana Japanese black pine Myoporum laetum Myoporum Pinus torreyana Torrey pine
Olea europaea Olive Pistacia chinensis Chinese pistache Parkinsonia aculeata Jerusalem thorn Pittosporum floribundum Himalayan pittosporum Persea americana Avocado Pittosporum undulatum Victorian box Phoenix canariensis Canary Island date palm Platanus racemosa California sycamore Phoenix dactylifera Date palm Platanus X hispanica London plane Phoenix reclinata Senegal palm Platanus X hispanica “Columbia” Columbia plane Ravenea rivularis, Majesty palm
Table 22. Tree Species Planted in San Diego that Are Also Planted in La Mesa, continued.

Scientific Name Common Name Scientific Name Common Name Platycladus orientalis Oriental arborvitae Pyrus kawakamii Evergreen pear Plumeria rubra Frangipani Quercus agrifolia Coast live oak Populus fremontii Fremont cottonwood Quercus coccinea Scarlet oak Prosopis chilensis Chilean mesquite Quercus ilex Holly oak Prosopis glandulosa Mesquite Quercus suber Cork oak
Prunus armeniaca Apricot Quercus virginiana Southern live oak Prunus avium Sweet cherry Ravenea rivularis Majesty palm Prunus blireiana Flowering plum Rhus integrifolia Lemonade berry Prunus caroliniana Caroline laurel cherry Rhus lancea African sumac Prunus cerasifera Purple-leaf plum Robinia pseudoacacia Black locust Prunus cerasifera “Purple Pony” Dwarf purple leaf plum Robinia pseudoacacia “Purple Robe” Purple robe locust Prunus domestica Plum Salix gooddingii Goodding’s willow Prunus ilicifolia Hollyleaf cherry Salix laevigata Red willow Prunus ilicifolia ssp. lyonii Catalina cherry Salix lasiolepis Arroyo willow Prunus persica Peach Salix matsudana “Tortuosa” Corkscrew willow Prunus serrulata Japanese flowering cherry Sambucus neomexicana Elderberry Psidium cattleianum Strawberry guava Schefflera actinophylla Queensland umbrella tree Pyrus calleryana Ornamental pear Schinus molle Peruvian pepper Olea europaea, Olive

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Table 22. Tree Species Planted in San Diego that Are Also Planted in La Mesa, continued.

Scientific Name Common Name Scientific Name Common Name Schinus terebinthifolius Brazilian pepper Triadica sebifera Chinese tallow tree Sequoia sempervirens Coast redwood Tristaniopsis laurina Water gum Spathodea campanulata African tulip tree Ulmus parvifolia Chinese elm Stenocarpus sinuatus Firewheel tree Ulmus parvifolia “Drake” Drake elm Strelitzia nicolai Giant bird of paradise Ulmus pumila Siberian elm Syagrus romanzoffianum Queen palm Washingtonia filifera California fan palm Syzygium paniculatum Brush cherry Washingtonia robusta Mexican fan palm Tecoma stans Yellow elder Wodyetia bifurcata Foxtail palm Tipuana tipu Tipu Xylosma congestum Xylosma
Trachycarpus fortunei Windmill palm Yucca gloriosa Spanish dagger Syagrus romanzoffianum , Queen Palm
Palms in La Mesa, CA

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of the City where it is needed most. For
example, areas with low canopy cover,
excessive hardscape, extreme heat, or
exposure to pollutants should be prioritized.

6. Set canopy cover goals for individual
parks and pursue opportunities to
increase canopy cover in City parks as park
development and redevelopment projects
occur.

7. Increase species diversity by planting
fewer palms and selecting new plantings
from the recommended species list when
palms and crape myrtles need replacement.

8. Consider a third-party company to
conduct another tree inventory in 3–4 years
to monitor the health and condition of public
trees.

Downtown La Mesa, CA
selection of moderate/medium water use rated
trees that may meet other urban forest goals
of the City.

Another important factor of the recommended
tree species list is the size classification of
trees. While large trees provide a higher level
of environmental services and benefits, large
stature trees are not always feasible to plant
in a dense urban environment. A mix of small,
medium, and large stature trees will help to
ensure that the City can progress towards
species diversity targets while also planting
trees suitable for the available space, a practice
commonly referred to as “right tree, right
place.”
The recommended tree species list in Table
23 was based on the factors discussed above,
and further refined in consultation with local
arborists and urban foresters who plant and
maintain City trees on a regular basis. The list
of species is a reflection of current information
on tree performance in the urban landscape,
available research, and climate change
predictions. This list will need to evolve and be
reviewed on a periodic basis to ensure it aligns
with current research and the experience of
arborists and urban foresters. Information
in the table about height, canopy spread,
spacing needed, and minimum parkway
width needed was sourced from the Urban
Forest Ecosystems Institute (UFEI). UFEI was
developed by the California Polytechnic State
University, San Luis Obispo, to address the
increasing need for improved management of
the urban forests in California (UFEI n.d.).

2.8 Urban Forest
Recommendations

1. Set achievable canopy cover goals and
develop a long-term tree planting strategy
for public and private tree planting. The
planting plan should use all available public
tree planting sites to the extent feasible,
prioritizing areas of low canopy cover first.

2. Include trees during the early planning
stages of projects to ensure trees are set up
for success and the largest possible canopy
trees may be selected and sited to provide
the maximum environmental services. Large
trees provide up to four to eight times the
environmental services as small trees. Tree
species should be selected based on their
anticipated size and available planting and
growing space in the ground and in the air
to avoid conflicts with existing or planned
infrastructure, such as sidewalks, curbs,
and underground/overhead utilities. Tree
selection will vary by location, and trees
should be selected in consideration of “the
right tree in the right place” concept (Arbor
Day Foundation 2021b).

3. Reduce/offset canopy loss by
creating ordinances for tree protection,
tree replacement, and canopy cover goals/
planting requirements by land use type.

4. Develop a private property tree
planting program. The City has limited
available planting space for additional
public trees and will need to rely on private
property owners to help increase canopy
cover. Additionally, the majority of the
City’s canopy cover is on private property,
and maintaining this existing canopy by
supporting private property owners is
essential to growing the urban forest. The
program could include a free tree program,
management and maintenance support, and
outreach and education for private property
owners about best management practices to
help expand the amount of large and healthy
trees on private property.

5. Identify opportunity and priority
planting areas to increase canopy in parts

74 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 75 Current Status of 2 the Urban Forest
Table 23. Recommended Tree Species for La Mesa
Genus Species Common Name
Evergreen,
Deciduous,
Conifer
Size Classificaiton
Height
(Feet)
Crown
Spread
(Feet)
Spacing
between
trees
(Feet)
Minimum
Parkway
Width
(Feet)
Water Use Classification of Landscape Species
(WUCOLS) rating
Regionally
Native
Afrocarpus falcatus Fern Pine E. Large 65 30-35 30-35 8+ Moderate/Medium Albizia julibrissin Silk tree D. Small 30-35 15-20 20-25 4 to 6 Low Arbutus unedo Strawberry madrone E. Small 20-35 20-35 20-25 3 to 4 Low Arbutus marina' Strawberry Tree E. Medium 30-40 20-30 20-25 6 to 8 Low Bauhinia blakeana Hong Kong Orchid D. Medium 30-40 20-25 20-25 4 to 6 Moderate/Medium Bauhinia purpurea Purple Orchid D. Small 30-35 20-35 20-25 4 to 6 Moderate/Medium Brachychiton populneus Kurrajong E. Medium 30-50 30 30-35 6 to 8 Low Cassia leptophylla Gold Medallion D/E. Small 20-25 25-30 20-25 4 to 6 Moderate/Medium Cedrus deodara Deodor Cedar C. Large 50+ 20-30 30-35 8+ Low Cercis candensis Eastern Redbud D. Small 25-35 25-35 20-25 3 to 4 Moderate/Medium Cercis occidentalis Western Redbud D. Small -20 -20 15-20 3 to 4 Low Yes Chilopsis linearis Desert Willow D. Small 20-30 10-20 15-20 4 to 6 Very low Yes Chitalpa tashkentensis Chitalpa D. Small 25-35 20-30 20-25 3 to 4 Low Yes Corymbia papuana Ghost Gum E. Medium 40-50 20-35 30-35 6 to 8 Low Geijera parviflora Australian Willow E. Medium 30-40 15-20 20-25 6 to 8 Low Handroanthus avellandedae Pink Trumpet D. Small 20-30 15-25 20-25 3 to 4 Moderate/Medium Jacaranda mimosifolia Jacaranda D. Medium 40-50 15-30 25-30 6 to 8 Moderate/Medium Koelreuteria paniculata Goldenrain D. Small 25-35 25-40 30-35 6 to 8 Low Koelreuteria bipinnata Chinese Flame D. Medium 30-40 15-30 25-30 6 to 8 Moderate/Medium Lagerstroemia indica Crape Myrtle D. Small 20-25 20-25 20-25 3 to 4 Moderate/Medium Laurus nobilis Sweetbay E. Medium 30-40 15-30 20-25 4 to 6 Low Yes Note: * Based on available data from McBride and Lacan 2018 and UFEI n.d..

Table 23. Recommended Tree Species for La Mesa, continued.

Genus Species Common Name
Evergreen,
Deciduous,
Conifer
Size Classificaiton
Height
(Feet)
Crown
Spread
(Feet)
Spacing
between
trees
(Feet)
Minimum
Parkway
Width
(Feet)
Water Use Classification of Landscape Species
(WUCOLS) rating
Regionally
Native
Ligustrum japonicum Japanese privet E. Small 10-15 5-8 20-25 3 to 4 Low Lophostemon conferta Brisbane Box E. Medium 40-50 30-Oct 25-30 4 to 6 Moderate/Medium Olea europae Fruitless olive E. Small 20-30 25-30 25-30 8+ Low Parkinsonia acuelata 'Cercidium'
hybrid
Palo Verde D. Small 20-30 20-25 20-25 4 to 6 Low Yes
Pinus eldarica Afghan Pine C. Large 70-80 15-25 20-25 8+ Very low Pinus torreyana Torrey Pine C. Medium 40-50 20-25 25-30 6 to 8 Low Yes Pistacia x 'red push' Red Push' Pistache D. Medium 25-40 20-40 30-35 4 to 6 unknown Pistacia chinensis Chinese Pistache D. Medium 30-35 25-30 25-30 6 to 8 Moderate/Medium Platanus mexicana Mexican Sycamore D. Large 50+ 25-30 30-35 8+ Moderate/Medium Prosopis chilensis Chilean mesquite D. Small 25-30 25-30 20-25 4 to 6 Low Prunus ilicifolia Hollyleaf Cherry E. Small 10-30 10-25 20-25 3 to 4 Very low Yes Pyrus calleryana 'Aristocrat' Aristocrat Pear D. Medium 30-40 15-20 20-25 4 to 6 Moderate/Medium Quercus ilex Holly Oak E. Medium 40-60 30-60 35-40 6 to 8 Low Quercus fusiformis Escarpment Oak E. Medium 30-50 20-40 30-35 6 to 8 Moderate/Medium Quercus engelmannii Engelman Oak E. Large 50-65 40+ 35-40 8+ Very low Yes Quercus suber Cork Oak E. Large 60-70 60-70 35-40 8+ Low Quercus agrifolia Coast Live Oak E. Large 40-70 20-70 35-40 8+ Very low Yes Rhus lancea African Sumac E. Medium 20-40 20-40 30-35 6 to 8 Low Tipuana tipu Tipu D./E. Large 40-50 40-50 35-40 8+ Low
Tristaniaopsis laurina Water Gum E. Medium 20-35 15-30 20-25 3 to 4 Moderate/Medium Zelkova serrata Sawleaf zelkova D. Large 50-65 50-65 30-35 8+ low Note: * Based on available data from McBride and Lacan 2018. Source: UFEI n.d.

CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 77

3. City-Managed
Trees
The City of La Mesa has compiled the policies
and practices to manage trees located in the
public space into the City’s Tree Policy Manual
(Manual). The purpose of the Manual is to
“provide a reference for existing City of La
Mesa guidelines, policies and standards for
the planting, care, preservation, maintenance,
replacement and removal of trees within the
public right-of-way and on private property”
(City of La Mesa 2013). The review of City
policies and practices of tree management will
include a thorough review of the Tree Policy
Manual, information provided in department
interviews, and Working Group meeting
discussions.

3.1 Governance Structure
Exhibit 1 provides the City of La Mesa
governance structure. The Department
of Public Works is responsible for the
management of trees in the public right-of-way,
per the policies and practices outlined in the
Tree Policy Manual. The parks maintenance
supervisor manages the population of Citymanaged trees, overseeing one staff member qualified to maintain street trees and the
contractor that performs scheduled City
managed tree pruning. The parks maintenance
supervisor is also responsible for park facilities,
the staff who maintain the park sites, and
various other duties for managing landscape
and streetscapes. When City staff are needed
to maintain street trees, a work crew of park
maintenance staff are pulled from their regular
duties to assist the City tree trimmer.

The City does not have an on-staff arborist to
assist in managing the City tree population,
and staff rely on their own experience with
trees when making maintenance decisions. City
staff recognized the need for a City arborist
and expressed that budget constraints and
limited workload make it difficult to support a
full-time arborist. One solution offered by City
staff is to potentially enter into an agreement
with adjacent municipalities to share the
cost of a full-time arborist. This is a creative
solution to address a City staffing issue and
warrants further exploration to determine if it
is a viable option. Another option could be to
increase the internal capacity by supporting
current staff members to receive the training
to become certified as an arborist.

Other staffing considerations to increase the
efficiency for managing public space trees
could be to separate the responsibilities for
managing park trees and park facilities from
street trees. This would allow for one staff
member to commit more time to the specific
issues related to park and street trees and
maintain tree safety in the public space.

3.2 Tree Policy Manual
The Tree Policy Manual covers “trees and
other landscaping located within or which

3. City-Managed Trees

78 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 79 3 City-Managed Trees
encroach into the public right-of-way,” with
trees on private property subject to the
policies outlined in the City Municipal Code.

The Manual is a thorough document with
standards and policies that address the major
components of street tree management,
including tree planting and establishment
care, pruning, removal and replacement, and
root pruning. Since the Manual is intended to
contain all tree-related policies, it is important
to ensure standards are clearly defined
and communicated to all staff who directly
manage trees, review tree applications, and
review development plans to ensure they
are appropriately implemented across all
departments.

As stated in the Manual, the City maintains an
inventory of all trees within the public rightof-way and is responsible for their continual maintenance. The following sections discuss
how the specific management actions of the
Manual align with best management practices
as defined by the International Society
of Arboriculture (ISA), American National
Standards Institute (ANSI) A-300, and emerging
trends supported by peer reviewed research.

3.2.1 Installation and
Establishment Care
Installation and establishment care practices
are inextricably linked as tree planting efforts
can be considered successful when trees
have established roots in the landscape
and are healthy. Ensuring a newly planted
tree establishes in the landscape depends
on the level of watering and care provided.

Conversely, poor planting practices can impact
future maintenance needs and may limit the
ability of a tree to establish in the landscape
even with ideal establishment care. The main
avenues for planting street trees in the City
and providing post-planting establishment care
are grant-funded, City-led capital improvement
projects; private property owners requesting
to replace an existing tree or plant an
additional tree along their property frontage;
and as a condition of a development permit.

Each of these planting situations are subject to
the establishment care standards of the Tree
Policy Manual.

TREE PLANTING

STANDARD DRAWINGS
The City’s standard drawings related to
tree planting and associated systems were
reviewed. This review revealed that the City’s
standard drawings contain elements that
align with ISA standards for tree planting
and staking. Of the standard drawings
reviewed, LMSD LS-1, Tree Planting and
Staking, and LMSD LS-2, Tree Planting and
Staking with Grates, are recommended
to be updated. Exhibit 2 presents LMSD
LS-1 and specific areas recommended for
updates are numbered. Table 24 provides
the corresponding recommended updates to
the tree planting and staking standard details
(updates shown on LMSD LS-1 should also
be carried over to LMSD LS-2). Additionally,
Appendix D includes ISA standard details
for tree planting and staking, and identifies
additional recommended updates that could
be adopted by the City or used to update the
current City standards.

PRIVATE PROPERTY

OWNER-INITIATED TREE PLANTING
New tree plantings in La Mesa are most
often initiated when private property owners
Exhibit 1. City of La Mesa governance structure.

80 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 81 3 City-Managed Trees
request a street tree planting in the public
right-of-way adjacent their property. This
approach is implemented in many cities
throughout California as the cities assume
the short-term cost of tree planting but
reduce the long-term financial commitment to
establishment care. Instead, private property
owners assume the labor and watering costs
to establish new trees.

In La Mesa, a private property owner may
request a street tree to be planted by
submitting an application to the City. While
the tree would be a City maintained tree
and would be added to the City's regular
maintenance cycle, the resident will be asked
to sign an agreement with the City that they
will be responsible for watering the tree
during its establishment (1-2 years). The
establishment care agreement, included as
Appendix E, informs tree recipients of the
commitment it will take to properly care for
the newly planted tree.

While this is a common practice, it has
shortcomings in its effectiveness to grow and
maintain tree canopy cover. One issue of this
model is the dependence on private property
owners agreeing to have a City-planted
Table 24. Recommended Updates to Standard Detail LMSD LS-1, Tree Planting and Staking U p d a t e
No. LMSD LS-1 Details Recommended Updated
1 Approved Hose & Wire Ties
Ties should be in middle portion of tree. Remove hose/wire from detail and replace with standard ties with information on what they are. 2 Lodge-Pole Pine Tree Stakes
Tree stakes are always needed on a 15-gallon or larger tree and should be installed in a way that can properly support vertical tree growth and trunk taper development.
3 8’ chemically treated or plastic root barrier along sidewalk/curb (new trees only) Min. 18” deep @ curb
Min. 12” deep @ walk
Root barriers should be installed on sidewalk side only; remove from detail on curb/street side. Root barriers should be installed at a minimum depth of 24 inches on the sidewalk side to be effective. 4 Approved backfill Backfill should be native soil
5 Actual root ball area; sloped 6” for drainage Remove slope; root ball should be resting on a flat soil. 6 Stakes to extend to a min. of 12” below root ball Stakes should be installed to a minimum depth of 24 inches 7 3-inch PVC perforated or corrugated drainpipe with
drain grate, on high side of tree well Remove from detail 8 Top of root ball min. 1” above existing soil Root flare should be no more than 1 inch above existing soil grade. 9 Notes: 2. Canopy shall not extend below 7’
Remove from detail. For newly planted trees this would allow for minimal to no lower branches that are needed to develop trunk caliper and would lead to “lollipop” trees.
10 Notes: 4. Fill standpipe with water weekly or as needed to keep from drying out, until fully established Follow watering guidelines, remove drainpipe. 1 2
3 4
5 6
7 8
9 10
Exhibit 2. LMSD LS-1 and specific areas recommended for updates.

82 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 83 3 City-Managed Trees
tree adjacent their property and to provide
establishment care. Often this approach
can have sporadic results in filling vacant
planting locations. Additionally, the reliance on
private property owners has the potential for
inconsistent watering and establishment care
practices that may lead to under-performing
trees or early mortality. Exhibit 3 provides a
recommendation for City establishment care
guidelines that can be provided to private
property owners so they understand the
needs of newly planted trees.

It is difficult to determine how well private
property owners provide establishment care
to newly planted trees. Based on the City
inventory data, 88.6% of street trees with a
DSH of 0 to 6 inches are in good health (Table
25), indicating a high level of care. This is also
supported by anecdotal evidence provided
by City tree managers who expressed in
interviews that private property owners
provide establishment care at a level that is
consistent with City standards.

Overcoming low participation in City tree
planting efforts and increasing knowledge
of establishment care needs can be difficult
without sustained education and engagement
of residents on the value of trees and
addressing issues that may make property
owners hesitant to have a tree planted.

To address this need, the City is currently
implementing an engagement strategy in
partnership with the nonprofit organization
Tree San Diego to increase the level of support
from residents.

The City received a California Department of
Forestry and Fire Protection (CAL FIRE) grant
to support the development of this UFMP and
to plant 350 trees in La Mesa neighborhoods
that are most vulnerable to pollution hazards.

Residents in target neighborhoods were
notified of the opportunity to have the City
plant a tree adjacent their property and to
participate in establishment care workshops.

The workshops were led by Tree San Diego
staff and provided information on the basic
steps private property owners can take to
ensure a healthy tree after it is planted, such
as watering guidelines, benefits of mulch, and
structural pruning. Despite extensive efforts
on behalf of the City and Tree San Diego to
inform residents of the opportunity, the rate
of participation from property owners has
been low. This does not necessarily mean
that the program is ineffective or that a
different model would achieve better results.

Rather it indicates that building support and
participation for City tree planting efforts is a
long-term effort that will take a commitment of
time and resources to shift public perception.

3.2.2 Pruning
Per the Manual, the City Public Works
Department is responsible for the pruning of
Weeding
■ Remove all the grass and
weeds growing in the tree
basin by hand.
■ To avoid root damage, do not
dig into the soil with a shovel
or hoe.
■ To avoid trunk damage, do
not use a weed whacker or
lawnmower for weed
removal.

Pruning
■ Newly planted trees may require
minor pruning to remove damaged
and or dead branches.
■ Trees should be pruned sparingly. All
other pruning should be withheld until
the second or third growing season
following tree planting.
■ Sucker growth (sprouts from the base
of the plant or from roots) should be
removed at any time.
■ All pruning should be conducted in
accordance with ISA pruning
standards.

Repair and extend tree basins
■ Newly planted trees should have a
4"–6" high berm just outside the
root ball to direct water to where it
is needed.
■ As a tree grows and matures,
extend the berm to the drip line.

Drip line
Ensure proper tree support
■ Tree stakes should be firmly
secured.
■ Leaning or loose stakes should
be re-installed immediately.
■ Tree ties should be placed in
the middle to lower portion of
the tree and allow for tree
movement.
■ When the roots of the tree are
established, remove the stakes
and tree ties. This typically
occurs 1 to 3 years after
planting.

Mulch
■ Apply mulch to a depth of 3"–4"
(slightly thinner on top of the root
ball).
■ Mulch should be an organic
material, such as leaf litter,
shredded bark, or wood chips.
■Keep mulch 4" from the trunk of
the tree.
■Replenish mulch at least 1 time
per year to ensure complete
coverage.

Tree Maintenance
Guidelines
Exhibit 3. Establishment Care Guidelines
Table 25. Health Condition of Street Trees with a DSH of 0 to 6 Inches Health Condition Total Percent of Total
Good 1,691 88.6%
Fair 157 8.2%
Poor 50 2.6%
Dead 11 .6%
Total 1,909 100%

ESTABLISHMENT CARE GUIDELINES

84 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 85 3 City-Managed Trees
all street trees either by City forces or private
contract. Street trees are on a 7-year prune
cycle that rotates each year through one of
seven maintenance zones (see Figure 9).

The intent of the regular pruning is to ensure
tree limbs and branches maintain 7 feet of
clearance above sidewalks and 14 feet above
streets. The City’s 7-year pruning cycle is
within the 5- to 7-year pruning cycle that is
considered the optimal timeframe for tree
pruning to ensure safety while minimizing
costs (Miller et. al 1981). This management
practice results in safer street trees and avoids
a loss of revenue from having to pay tree
related settlements. This is evident by City data
that shows only 12 accident claims related to
City tree limbs between July 2014 through June
2019, which resulted in paying damages of
$2,000 total for all claims.

The Manual also states that “trees will be
thinned out and or have their crowns reduced”
as part of the scheduled tree pruning (City
of La Mesa 2013). Tree pruning in an urban
forest is a practice to manage trees in a built
environment to promote sound structure that
contributes to safer trees with reduced risk to
people and property. The structure of each
tree must be evaluated within its surrounding
environment to determine the goals for
pruning a tree before one begins to make cuts
and remove tree parts. A generalized practice
of thinning or reducing crown size should be
removed from the manual and replaced with a
policy based on individual tree needs.

In addition to the scheduled City-conducted
pruning, it was reported by City staff that
private property owners may prune their
street tree with approval from the City. This
helps to reduce the City’s costs to maintain
the street tree population, but the City is still
responsible for any damage that tree may
cause. Improper pruning practices can result
in trees with compromised health and safety.

By providing approval for private residences
to prune trees adjacent their property, the
City has less control over ensuring these trees
are properly pruned for maximum health and
safety of the tree. If the City continues to allow
private property owners to prune the street
tree adjacent their property, the City could
reduce their liability for tree claims by requiring
the property owner to sign an agreement
to assume the responsibility for any liability
claims that could occur from tree part failure.

The current Tree Planting and Maintenance
Agreement provides a framework for the
City to develop an agreement to address the
specific liability concerns of a private property
owner who desires to prune the street
tree adjacent their property. The City could
also provide property owners with a list of
approved tree trimmers and/or guidelines for
proper tree pruning practices.

3.2.3 Removal and Replacement
Tree removal is only allowed by the City
under certain cases and when approved by
the Director of Public Works. The City lists
eight conditions under which tree removal is
permitted. The conditions are as follows:

1. The tree is dead.

2. The tree is damaged, diseased, or
infested beyond the point of saving using
reasonable horticultural practices, or
should be removed to prevent the spread
of disease or infestation.

3. The tree is uprooted and a hazard.

4. The tree is damaging improvements
such as pavement, curb and gutter, and
sidewalk, and all options such as root
pruning, re-routing of improvements
around the tree, or other methods
which may become available, have been
considered but deemed infeasible.

5. The tree is damaging private
improvements and methods described in
number 4 above are not feasible.
8 8
8 125
125
125
94 94
Broadway
w
Lake Murray Blvd
Lemon Ave
Baltimore Dr
Jackson Dr
El Cajon Blvd
University Ave
Spring St
El Cajon Blvd
1 2
3 5
8 4 7
6 Figure 9. La Mesa Maintenence Zones

86 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 87 3 City-Managed Trees

6. The tree is deemed by the Department
of Public Works to be a substantial hazard
to traffic or pedestrians, and all other
reasonable alternatives are deemed
infeasible.

7. The tree is noxious, a public nuisance,
or is otherwise a safety or health risk.

Property owner dislike or dissatisfaction
with a particular street tree shall not
be grounds for removal, unless strong
medical or other reasons are documented
to the satisfaction of the Public Works
Superintendent.

8. Root intrusion into a private sewer
lateral shall not be grounds for removal
of a tree. Root intrusions shall be handled
in a manner consistent with the revised
sewer lateral maintenance policy adopted
December 24, 2012.

Overall, the conditions for tree removal
are clear and place the emphasis on tree
preservation before removal when trees
conflict with infrastructure. When trees are
lifting sidewalks and damaging curbs, gutters,
and private property removal may ultimately
be the only solution in each circumstance but
is considered the last option. The methods
identified in condition 4 do not encompass all
possible alternatives and could be expanded
to include reinforcing sidewalks, structural
soils, and suspended pavements (see
Appendix F for additional sidewalk and tree
conflict resolution strategies). Suspended
pavement systems are already required
when a street tree is required to be planted
as part of a condition for a redevelopment
project (see Section 4.1.2 for a discussion of
suspended pavement requirements per La
Mesa Standard Drawings LMSD WQ-03 Storm
Water Treatment Curb Inlet for Silva Cell, and
WQ-04 Modular Root Management System).

This provides the City an already existing policy
that can be implemented in other locations.

Determinations of tree retention should
be made by an ISA-Certified Arborist with
experience in tree preservation. As such, the
conditions could also include a requirement
that an ISA-Certified Arborist prepare a report
for the application that discusses the reason
for tree removal and why alternative methods
are not feasible.

3.2.4 Root Pruning
Street trees planted in urban environments
at times will come into conflict with adjacent
sidewalks, tree wells, curbs, and other
infrastructure that will need to be repaired
to maintain the location in a safe condition.

Every effort should be made to preserve trees
when repairing damaged infrastructure. Prior
to root pruning activities, alternative designs
and materials should be evaluated that will
minimize impacts to tree health and safety (see
Appendix F). When impacts to trees and tree
roots cannot be avoided, careful consideration
must be given to determine if root pruning and
tree preservation is feasible.

Improper root pruning and unnecessary
damage from construction-related activities
can significantly damage trees, resulting in
health decline and/or structural instability. In
the event that root pruning is necessary to
preserve the tree(s), the following guidelines
may be used to inform the decision-making
process and decrease the likelihood of tree
health decline and/or structural stability prior
to and following root pruning.

Minimization of root damage is best
accomplished by minimizing overall root
pruning and maximizing the distance from the
tree’s trunk that roots are cut. Each tree and
situation is unique, and requires a decisionmaking process. As such, the City should require the following qualifications of any
individual who will make recommendations for
trees that require root pruning:
• ISA-Certified Arborist
• ISA Tree Risk Assessment Qualified
• Experience with root pruning Foundation
for the Standards
The City of La Mesa recognizes the most
current editions of the following pruning
standards:
• American National Standards Institute
(ANSI) A300 Pruning Standards
• ANSI Z133.1 Safety Standards
• ISA Best Management Practices: Tree
Pruning
Step 1 – Tree and Site Assessment
To minimize root-pruning impacts, a tree
assessment will be conducted by a Cityqualified arborist prior to pruning. During the evaluation, the arborist will evaluate tree and
site conditions to determine the potential for
injury and loss of structural stability. Tables 26
and 27 provide guidelines to determine if the
tree is a suitable candidate for root pruning.

If the assessment finds the tree is a suitable
candidate for root pruning, constructionrelated activities can commence under the supervision of a City-qualified arborist.

Step 2 – Root Pruning
A City-qualified arborist will be on site during Tree trimming

88 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 89 3 City-Managed Trees
Table 26. Tree Health and Safety Factors to Consider
Factor Description
Tree Species Some species tolerate root pruning/damage better than others.

Tree Health Trees in poor or declining health should not be root pruned.

Tree Age Older trees are more likely to decline following root pruning and/or damage.

Tree Lean Leaning trees should not be root pruned.

Root Pruning Damage Proximity The closer that the root cut is to the tree, the greater the chance of tree decline and loss of stability.

Percentage of Anticipated Root Loss More loss increases the likelihood of decline.

Structural Root Damage Increased likelihood of structural failure and increased risk to the community.

Prior Root Pruning Trees that have had prior root pruning should be documented to minimize additional decline.

Soil Volume Roots in shallow soils require additional distancing from the trunk of the tree to minimize the likelihood of root damage.

Table 27. Long-Term Objectives to Consider
Factor Description
Future Site Development The tree will require removal due to a pending project.

Sustainability The tree species does not meet the City standards for water use, drought tolerance, and adaptability to changing climate conditions.

Increasing Canopy Cover An alternative species in the same location would provide increased canopy coverage to meet the goals of the City.
construction-related activities to monitor
impacts to the tree and roots. If root pruning is
required, root pruning will be minimized to the
extent possible. The following guidelines are
examples of potential root pruning approval
conditions that will help guide the decisionmaking process prior to root pruning.

Conditions to Determine Possible Tree
Candidates:
• The tree appears to be in good health and
a safe condition as determined by a Cityqualified arborist. • The tree species meets the City standards
for water use, drought tolerance, and
adaptability to changing climate conditions.
• The tree species provides a maximum
level of canopy cover for the growing space
provided in the ground and air.

Suitable Conditions for Root Pruning:

1. The roots to be pruned are greater than
or equal to 5 feet from the tree’s drip line.

2. The root measures < 2 inches, and:
a. is a distance from the trunk of more
than 5 times the diameter of the trunk.
b. pruning is less than 30% of the total
root system.

Conditions that Require a Determination
by a City Arborist Inspector:

1. Any disturbance within the dripline of
the tree.

2. Any root cutting within 5 times the
diameter of the trunk of the tree.

3.3 City-Managed Trees
Recommendations
City Managed Trees – Specifications and
Details

1. Update standard detail LMSD LS-1, Tree
Planting & Staking, and LMSD LS-2, Tree
Planting and Staking with Grates
City Managed Trees – Installation, Management and Maintenance

1. Establish a monitoring schedule to evaluate trees for potential pest and disease infestations.

2. Update the language in the Tree Policy
Manual for thinning and reducing crowns
to reflect the City’s goals for trees and the
urban forest.

3. Develop a maintenance agreement for
private property owners who desire to
prune the street tree adjacent their property, that results in the property owner assuming responsibility for the risk and any
liability claims that may arise for limb or
whole tree failure.

4. Adopt tree establishment care guidelines.

Explore options to provide establishment
care to all newly planted trees in the City for
a minimum of 3 years.

Jacaranda mimosifolia, Jacaranda

90 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 91 4 Private Property Trees

4. Private
Property Trees
To have a sustainable urban forest, the
planting, pruning, and maintenance of a
city’s trees must be coupled with effective
policies and ordinances that adhere to best
management practices, protect and preserve
trees, and have penalties sufficient enough
to deter them from being violated. These
pillars work in unison to protect and grow
the investment a city makes in trees and
the services they deliver as a return on that
investment. Throughout the UFMP process,
the City recognized the need to protect and
preserve trees on private property. This
section discusses current City policies and
ordinances for private property and provides
guidelines that can be used by the City if they
choose to develop a protected tree ordinance.

4.1 Tree Policies and
Ordinances for Private
Property
The City of La Mesa Tree Policy Manual (City of
La Mesa 2013) lists two goals directed toward
the preservation and protection of trees on
private property:
• The City values trees for their role
in processing carbon dioxide in the
atmosphere, and will continue efforts to
save existing trees and to require planting
of new trees in conjunction with public and
private developments. (La Mesa General
Plan - Conservation and Open Space
Element -Conservation Policies - #5 -p. 3)
• The Community Development Department
will review the Zoning Ordinance to
consider what standards can be added
to preserve and protect stands of mature
trees within the City. (La Mesa General Plan
- Conservation and Open Space Element -
Conservation Objectives - #2 - p. 4)
The City does not have a tree protection
ordinance to protect and preserve trees on
private property, and as such, any tree on
private property can be removed without
oversight from the City. There is not sufficient
data to determine the extent to which tree
removal on private property has impacted the
urban forest and canopy cover in La Mesa. A
2017 study determined that redevelopment
of single-family home lots in the County of
Los Angeles between the years of 2000–2009
resulted in a loss of 14% to 55% of green cover
per lot (Lee et. al.). This research reflects the

4. Private Property Trees

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significant impact private development can
have on the urban forest and the potential to
preserve canopy cover through an effective
ordinance.

While a tree protection ordinance would not
prevent all tree removals, it would increase
the frequency of trees being preserved during
site development and require tree planting to
replace lost canopy. Successfully implementing
a tree protection ordinance would require
penalties sufficient to deter violation and
a commitment of City resources to enforce
the ordinance. It would also require a public
education campaign to notify and inform
private property owners of the new ordinance
and the process for applying to remove a
protected tree(s). The investment of resources
to institute a tree preservation ordinance may
exceed current budget constraints but is worth
considering as it will be key to achieving Citywide canopy cover goals outlined in this UFMP and the CAP.

The positive or negative impact private
property owners can have on the City-wide
urban forest was thoroughly discussed with
City staff and working group members as
most City-wide canopy cover exists on private
property. The working group discussions
covered a multitude of options to increase
canopy cover on private property. The
consensus was a preference to encourage
private property owners to voluntarily
adopt City arboriculture standards through
community education and engagement efforts
as opposed to enforcement of an ordinance.

The preference was in part due to the City’s
political climate, in which residents could view
a tree protection ordinance as an infringement
on property rights. The online survey results
suggest otherwise but not enough surveys
were completed to make a statistically relevant
conclusion.

4.1.1 Zoning Ordinace
The goals of the Zoning Ordinance have
been reviewed below to address the existing
standards to preserve and protect mature
trees in the City. Table 28 presents the
current Zoning Ordinance standards that
relate to trees. The Zoning Ordinance policies
provide a framework and examples of various
ways the City enforces standards on private
property that can be used to develop a tree
protection ordinance. The Zoning Ordinance
includes standards to preserve trees during
site development, replacement ratios,
requirements for trees to be planted on
residential property, size specifications for
tree planting, and maintenance requirements.

The City’s Zoning Code also includes adopted
overlay zones that provide modified provisions
for specific areas within the City. The overlay
zones listed below contain policies related to
trees that are unique to the underlying area.

Tree-related policies are listed in Table 28 and
further discussed below.
• Chapter 24.09 Scenic Preservation Overlay
Zone
• Chapter 24.10 Brier Tract Overlay Zone
• Chapter 24.17 Bowling Green Overlay Zone
• Chapter 24.18 Mixed Use Overlay Zone
Chapter 24.09, Scenic Preservation Overlay
Zone, establishes regulations to preserve
the visual character and quality of views in
the City’s recognized scenic areas. Trees are
a key component that help define the scenic
character of an area, adding visual relief
and softening the contrast of development.

As such, a tree protection ordinance can
be an important part of maintaining scenic
quality. Section 24.09.040, Requirements for
Landscaping and Maintenance of the Scenic
Preservation Overlay Zone, describes a
process similar to a tree protection ordinance
by requiring a landscape plan that shows
details of the trees proposed to be removed
Table 28. Tree Policies of the Zoning Ordinance
Chapter Section Policy
Chapter 24.05 -

RESIDENTIAL ZONES

AND DEVELOPMENT

STANDARDS

8. Accessory dwelling units, attached and detached.x. Within the Bowling Green Overlay Zone, any tree that was required to be planted pursuant to Municipal Code Section 24.17.030D that is disturbed by a project to construct an accessory dwelling unit shall be preserved in place, or replaced in kind on the subject property if disturbed by the project.

24.05.035 - Planned
residential developments.

D. PRD–Required Findings All findings required by this Title to approve a use or development which is proposed within, or as part of, a PRD [planned residential development] shall be made. In addition, to approve a site development plan for PRD development or modification, the following findings shall be made:

The site has not been substantially altered within twenty-four months prior to submittal of the project application to the planning department and prior to consideration of the project. Substantial alterations include, but are not limited to, the removal of mature trees, the removal of significant vegetation, the removal of wildlife habitat, grading, or similar changes to the site which are inconsistent with the intent and purpose of the Planned Residential Development.

24.05.040 - General
provisions.
. MAINTENANCE OF PROPERTY REQUIRED—RESPONSIBILITY.1. All yards and other open spaces around buildings shall be kept free of junk including but not limited to trash; refuse; paper; glass; cans; rags; fabrics; bedding; ashes; trimmings from lawns, shrubbery or trees, except when used for mulch;

2. All landscaped areas shall be regularly watered, fertilized, weeded and otherwise kept in good condition. Dead, decayed, or hazardous trees or other vegetation which is likely to harbor rats or vermin, or is dangerous to public health and welfare is prohibited. All trees, shrubs, lawns and other planting shall be maintained, including regular irrigation, pruning of trees, trimming of shrubs and cutting of lawns. Landscaped areas shall be covered with natural materials or other materials whose general use is intended for use as outdoor landscaped material. Unnatural or synthetic materials, such as but not limited to carpet, plastic sheeting, or paper products are prohibited.

Note: Bolding added to highlight discussion of trees.

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Table 28. Tree Policies of the Zoning Ordinance
Chapter Section Policy
Chapter 24.09 - SCENIC

PRESERVATION OVERLAY
ZONE — P

24.09.020 - Limitations on permitted uses and
structures.

A. The improvement of the building site either initially or after a principal use has been established shall not involve alteration of the surface of the land by construction, excavation, filling, or otherwise, through which trees would be removed, water courses would be altered, or earth banks exceeding 3 feet in height would be created unless the development is first submitted to and approved by the Planning Commission.

24.09.040 - Requirements for landscaping and
maintenance.

All building sites shall be landscaped and maintained. In connection with each proposed development a landscaping plan shall be submitted with application for building permit. Such plan shall show location, size, and type of all trees proposed to be removed together with the size, location, and type of all trees proposed for replacement. All specimen trees shall be replaced with healthy trees also of specimen size except where this requirement is relieved by the Planning Commission upon justification.

Chapter 24.10 - BRIER

TRACT OVERLAY ZONE
— BT*

24.10.02 - Development standards. C. Landscaping: Regardless of any other standard, four trees shall be required on every lot within the Brier Tract Overlay zone. Two of the required four trees shall be placed in the front setback area and the required trees shall be not less than ten feet high and three inches in girth.

Chapter 24.17 - BOWLING

GREEN OVERLAY ZONE

24.17.030 - Development standards. D. Landscaping. A minimum of three 36-inch boxed trees shall be planted on a lot prior to occupancy of any single-family home constructed after December 1, 1985.

Chapter 24.18 - MIXED
USE OVERLAY ZONE—MU

24.18.010 - Effect of chapter. B. 2. Increase opportunities for infill housing while transforming and aesthetically improving transportation corridors into tree-lined civic boulevards with mixed use projects;

24.18.040 - Development standards. E. Open Space.

5. A minimum of twenty-five percent of the common space shall be planted area including trees, shrubs and gardens. Planters and planting containers may be counted toward this requirement.

Note: Bolding added to highlight discussion of trees.
and planted. The language could be improved
by stating that an arborist’s report should be
prepared for the proposed removed trees to
ensure accurate tree information is presented
to the City. The tree replacement policy also
needs clarification as to what constitutes a
specimen size tree and appropriate species
and a replanting ratio that is directed towards
the City’s canopy goals.

Chapter 24.10, Brier Tract Overlay Zone,
establishes development standards for
the residential area that fronts Brier Road,
Bramble Road, Briercrest and Nokomis in the
Brier Tract. Trees in this portion of the City
contribute to the rural and rustic character in
the area. Chapter 24.17, Bowling Green Overlay
Zone, establishes developmental standards
and regulations for the Bowling Green Drive
area. It is notable that the development
standards for both the Brier Tract Overlay
Zone and Bowling Green Overlay Zone have
requirements for trees to be planted on
private property, setting a precedent for more
direct management by the City for trees on
private property. A combination of community
education and ordinances is one approach
to tree management on private property
that provides an opportunity for voluntary
compliance before the enforcement of an
ordinance. Whichever path the City chooses,
it has a precedent of policies that support a
tree protection ordinance for private property
trees and will need to direct resources toward
a robust education campaign.

Chapter 24.18, Mixed Use Overlay Zone,
establishes development standards and
regulations for the land uses, structures, and
lots that abut El Cajon Boulevard, University
Avenue, and La Mesa Boulevard, or that
are near the Spring Street Trolley Station.

The development standards apply to new
construction of mixed-use projects and
residential-only projects in the area. Through
policies and regulations in this overlay zone,
trees are intended to improve the aesthetics
of the area by adding them to common areas,
new development, infill development, and
transportation corridor improvement projects.

4.1.2 Landscape Standards
The La Mesa City Council has adopted landscape
standards that contain provisions for landscape
plan review, landscape design, installation and
maintenance, water efficiency, erosion control,
and street tree selection. These landscape
standards are complemented by the City’s
Water Efficient Landscape Ordinance, which
was adopted pursuant to statewide measures
(Assembly Bill 1881 [Water Conservation in
Landscaping Act of 2006]) to reduce water use
in landscapes as a result of ongoing drought
conditions. The landscape standards include
Landscaping

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requirements for the design and installation
of trees, shrubs, turf grass, and irrigation, and
serve as the other main avenue by which the
City directs tree management activities on
private property. The landscape standards
apply to all new and rehabilitated landscapes
on public agency projects, private industrial and
commercial projects, multiple-unit residential
projects, and developer-installed landscaping in
single-family residential projects. The purpose of
the standards is to:
• Promote the values and benefits of
landscapes while recognizing the need
to invest water and other resources as
efficiently as possible.
• Establish a structure for designing,
installing, and maintaining water-efficient
landscapes in new projects.
• Establish provisions for water management
practices and water waste prevention for
established landscapes.

Compliance with the landscape standards is
often hindered by enforcement issues that
were expressed in interviews with City staff.

The language of the landscape standards
includes final review of installed landscapes by
the Community Development Department, but
does not provide a mechanism to penalize the
site developer for noncompliance or conduct
additional site inspections.

Landscape and irrigation plan review is
required by the City to demonstrate compliance
with state-mandated water conservation
requirements, the City’s landscape standards,
and the Water Efficient Landscape Ordinance
(Chapter 14.29 of the Municipal Code). This plan
review is required for new construction projects
with an aggregate landscape area greater than
500 square feet and rehabilitated landscape
projects with an aggregate landscape area of
at least 2,500 square feet requiring a building
or landscape permit, plan check, or design
review. Landscape plans are reviewed by the
City’s landscape architect and must include a
sufficient level of detail to ensure landscape and
irrigation requirements are met. However, not
all landscape plans require review. The City also
offers a prescriptive compliance option for new
water efficient landscape installations between
500 and 2,500 square feet. Such projects are not
required to undergo landscape plan submittal
and review.

Applicants must pay a deposit for the landscape
plan review, which is calculated based on the
total anticipated landscaping costs and covers
the cost to process applications and review
submissions. The fee could also include the
cost for a third-party independent consulting
arborist to review applications to ensure
arboriculture standards are accurately reflected
in applications. Cities often utilize third-party, oncall arborists as a means to provide review of site plans and tree removal applications when they
do not have an arborist on staff. Independent
review can be advantageous for the objective
opinion that is not representing a specific
interest (site developer or property owner). This
can have the benefit of reduced staff time to
make decisions on site plans, permit applications,
and preparing reports for elected officials.

Tree-related standards from the Landscape
Ordinance are provided in Table 29 and detailed
in the following paragraphs.

LANDSCAPE PLAN AND DESIGN
Some of the City’s landscape standards are
specific and detailed in what is required
while others are not. One of the main ways
the ordinance impacts trees is through the
requirement of 1 tree for every 500 square feet
of landscaped area. The standard does not
stipulate a minimum size requirement for the
tree to be planted within the landscaped area
and would allow for small stature trees that
provide a lower environmental benefit. If the
project covered 2,000 square feet of landscaped
Table 29. Tree-Related Landscape Standards
Section Standard
Landscape
Plan Design
• All areas should be provided with a mixture of groundcover, shrubs, and trees. Trees shall generally be in minimum 15-gallon containers and shrubs in 5 gallon containers, except where approved by the Community Development Department (or by the Public Works Department where appropriate)
• At least one tree shall be provided for every 500 square feet of landscaped area (except in public parks, subject to approval by the Public Works Department). A minimum of 20% of the trees shall be specimen size (i.e., in 24" box or larger containers). Additional trees may be required for screening or to provide vertical scale as a requirement of the Design Review process. • Existing mature trees should be preserved and incorporated into the landscape design wherever feasible and appropriate.

Specifications and
Details
• The plans shall include the details for the installation of trees and shrubs, including details for the staking and guying of all trees. • The location, type and caliper size of any existing mature trees to remain, to be relocated, or to be removed. If mature trees are removed due to grading or other reasons, replacement specimen size trees may be required.

Installation
and maintenance
• All trees, shrubs and groundcovers should be free of insects, pests, or fungus disease or the effects of previous infestations. They should have normally well developed branch systems and a vigorous and fibrous root system which is not root or pot bound. • Trees shall be staked or guyed until they are self-supporting. • All trees, shrubs, and groundcovers which have been planted and which due to accident, disease, or other cause, fail to show a healthy growth within one year should be replaced.
• Watering should be scheduled between the hours of 2:00 AM and 10:00 AM to avoid irrigating during times of high wind or high temperature.

Deep watering practices shall be utilized to promote deep rooting of trees and shrubs. • Trees and shrubs should be trimmed or pruned to prevent blocking or interference with the following:
• Sight distance views.
• Pedestrian or motor vehicle access.
• Installation, maintenance or repair of any public utility or fire lane. • Damage to property line fences or structures on adjoining properties.

Street tree
Program
• Street trees are encouraged for all new developments. In areas where a Specific Plan does not identify approved street tree selections, trees may be chosen from the approved Street Tree List which may be obtained from the Public Works Department. • In established neighborhoods with an existing mature street tree pattern, street trees should be selected to match the existing street trees in the vicinity.
• Street trees shall be planted at a minimum of one 15-gallon tree per 40 feet of lineal street frontage. Trees may be placed on center or clustered in groups, dependent on the prevailing pattern in the neighborhood. • Trees shall be selected and maintained so that upon maturity a minimum distance of 60 inches clear is maintained between the finish grade and the lower branches.
• Other street tree requirements may be required by the Director of Public Works.

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area, four small trees, such as a western redbud
(Cercis occidentalis), could be planted to meet
the requirement. Updating the standards so the
tree planting requirement is based on reaching
a canopy cover target for the area may result in
fewer trees planted on site, but a greater canopy
cover area and shade provided, as medium- to
large-canopy trees would cover more area.

Additionally, the environmental benefit would
increase as medium- to large-canopy trees can
provide 4 to 8 times the benefit of a small canopy
tree.

The standards also state that existing mature
trees “should” be preserved whenever feasible
and appropriate, but this is not required as the
City does not have a tree protection ordinance.

The landscape standards could be updated to
state that existing mature trees can meet the
canopy cover requirement for the landscaped
area instead of planting new trees. While planting
new trees can add new canopy in areas where
there is little to no canopy, recovering lost canopy
will take years and may never fully recover the
extent of lost canopy if a large stature tree is
replaced with a small stature tree. Preserving
existing canopy cover is an important part of
reaching City canopy cover goals to ensure newly
planted trees are adding to existing canopy cover
rather than only replacing lost canopy. Preserving
trees on site also ensures a continuation of the
high level of environmental services provided by
medium- to large-stature trees. A goal of 75%
canopy cover per square foot of landscaped
area would provide sufficient cover of the site
and encourage the preservation and planting
of medium- to large-stature trees. This type of
requirement is also aligned with City canopy
cover targets of the CAP and this UFMP.

SPECIFICATION AND DETAILS
The City’s tree planting specifications and
details state that site plans should include
the location, type, and caliper size of existing
matures trees to be relocated or removed.

This language should be updated to require an
arborist’s report by an International Society of
Arboriculture (ISA) Certified Arborist to verify the
required tree information. It should also include
a discussion of why tree removal is required, an
explanation about why tree preservation is not
feasible, and guidelines to protect trees during
construction if trees are to be preserved during
site development. Since the City does not have
an arborist on staff, a third-party consulting
arborist could be required to further review the
report for its accuracy and make an independent
determination if tree removal is justified.

INSTALLATION AND MAINTENANCE
The landscape standards do not provide enough
detail for the installation and maintenance of
trees in the landscape to clearly define the
requirements. This practice can be improved
by providing site developers a modified version
of the City LMSD standard details based on ISA
industry best management practices for how to
properly plant, stake, maintain, and prune trees.

The installation standards can also be improved
by including industry standards for nursery stock
selection to encourage the planting of trees
with root and branch structure to support its
long-term health and safety. Details for these
standards are provided in Appendix D.

STREET TREE PROGRAM
The Street Tree Program is the final section of
the landscape standards that discusses trees.

Like other aspects of the standards, street tree
planting is encouraged but not required, which
is reasonable given that projects would most
likely not impact street trees. However, the site’s
canopy cover requirement could be met by a
street tree if the landscape area is adjacent a
vacant street tree planting location. Allowing a
street tree to count towards the canopy cover
requirement would have an added benefit to
the general public of shading the sidewalk and
reducing stormwater management by the City.

Suspended pavement systems are required
by the City when a street tree is required as
a condition of approval for a development or
redevelopment project. La Mesa Standard
Drawings LMSD WQ-03 Storm Water Treatment
Curb Inlet for Silva Cell, and WQ-04 Modular
Root Management System, outline requirements
for suspended pavements for street tree
installation. Suspended pavement systems
consist of structural support modules under
concrete/pavement that create a void space
to be filled with soil, making lightly compacted,
high-quality soils available for tree roots urban
environments. A study from the Bartlett Tree
Research Lab (Bartlett Tree Experts 2015)
revealed that suspended pavements resulted
in significant improvements in tree growth,
foliage color, root growth and crown dieback
compared to alternative soil. Insufficient usable
soil for root growth is a major limiting factor
for urban trees, resulting in root bound trees
and conflicts with hardscape. With suspended
pavement systems, nearly all of the space (94%)
under the sidewalk is available for root growth. In
addition to promoting healthy urban tree growth,
suspended pavement systems also aid in on-site
stormwater management (Bartlett Tree Experts
2015).

To improve tree health, the City can use
its existing standard drawings and expand
these requirements to all development or
redevelopment throughout La Mesa, and
not only when street trees are installed as a
condition of approval.

4.2 Developing a Tree
Protection Ordinance
The goal of the protected tree ordinance is to
move the City closer toward achieving its vision
for the urban forest as expressed in the UFMP.

Specifically, the vision statement articulates
the value and importance placed by the City
to ‘foster a sustainable urban forest that
supports residents living in an equitable, healthy
environment, resilient to climate change’, as
trees are inextricably connected to preserving
and enhancing the quality of life for La Mesa
residents. The following guidelines are intended
to give the City a clear understanding of what
is included in a tree protection ordinance,
examples from other regional jurisdictions, and
draft language that can be developed into a City
ordinance.

4.2.1 Guidelines

4.2.2 Clear Staff Responsibility
The effectiveness of a protected tree ordinance
largely depends on whether it can be enforced.

This begins with clearly defined roles and
responsibilities for the City staff charged with
implementing the ordinance. There should be no
ambiguity in the language of the ordinance as to
who has the authority to do the following:
• Make final decisions on permit approval.
• Enforce penalties if the ordinance is
violated.
• Review permits to prune or remove
protected trees.
• Review appeals on denied permits.

A key decision in deciding City staff responsibility
is determining what department(s) will manage
the application process from permit review and
approval, to enforcement of tree replacement.

Protected tree ordinances have a bifurcated
nature in that they cover private property
trees, under the purview of Community
Development, and public right-of-way trees
under the purview of Public Works. Often, all
private property permit review is housed in
one department, including those related to a

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protected tree ordinance. While this streamlines
city coordination of permit review, it can also
place arboricultural decisions on staff who are
not arborists or tree experts. This must be
avoided to ensure permits for tree removals
are only issued when they meet the standards
of the ordinance. An arborist should review all
tree-related issues, so the best arboricultural
determinations are used in processing tree
permits.

Budget constraints impact the ability of the City
to have an on-staff arborist. In the absence of
a City arborist, the City could contract with a
third-party consulting arborist to review permit
applications using standards of arboriculture.

4.2.3 Scope of Ordinance
Protected tree ordinances determine what is
protected by either species defining specific
tree type, size, or both. Other narrower species
definitions include trees being defined as a
“heritage” tree in a city General Plan, or trees
that are considered native to the city or region.

The definition and criteria of what qualifies a
tree as “protected” can widely sway how many
trees will fall under protection in the ordinance.

The discussion below examines these criteria
through the lens of the vision statement and
goals for the program to provide a framework for
City decision makers on the scope of what will be
protected.
• Size: The most consistently used standard
for determining status as a protected tree
is its diameter at standard height (DSH).

DSH is the diameter of the trunk measured
4 feet 6 inches from the base of the trunk.

There is not a set best management
practice for a City to follow in determining
a DSH standard for an ordinance,
and standards can widely vary. Some
ordinances protect trees when they reach
a DSH range of 4 inches to 8 inches to
provide more protection of specific species
like native or heritage trees. Cities with a
larger selection of protected species, or no
species designation at all, will use a higher
DSH standard that can range from 14
inches to 36 inches.
• Species: Tree species are typically
protected when they have a significant
environmental or cultural value to a
City. The determination of significance is
specific to the City, as every City has its
own unique history, native species, and
culture. The role of the City is to examine
those factors and conclude if that will be
one part for determining if a tree species
should be protected.
• Native trees: Native tree species support
biodiversity within an area by providing
habitat for regionally native birds, animals,
and insects. Native trees are also culturally
relevant for the indigenous peoples
that originally inhabited the Southern
California area. These two factors are why
many cities have adopted protected tree
ordinances that include native Southern
California tree species.
• Heritage trees: Heritage trees are a
unique definition in a protected tree
ordinance as it designates specific
individual trees, and not general guidelines
of species or size. This designation
identifies trees that the City and residents
consider to have a significant cultural
value to the community. This can include
individual trees, groups of trees that are
historic, a unique or exceptional specimen,
or remnants of previous agricultural
land uses. These standards should be
considered for drafting a provision of the
protected tree ordinance for heritage
trees.

4.2.4 Enforcement
For a tree protection ordinance to be effective, a
City must be committed to consistently enforcing
the ordinance and established penalties. The
overall environmental and economic value of the
tree is one consideration for determining what an
appropriate fine is. Some valuation methods can
calculate the financial value significant trees add
to a property in the tens of thousands of dollars.

The environmental services of a tree-like carbon
sequestration, avoided stormwater runoff,
and lower energy temperatures have a real
and quantified economic value to the City. On
average, it would cost La Mesa $2,077 to replace
the environmental services a tree provides. The
following discussion explores frequently used
methods for penalties/fines to help the City
determine what it considers a sufficient penalty.
• Administrative fines are essentially a
ticket issued to the private property owner.

These fines usually begin around $250
and increase in the amount per violation.

If a violation is considered particularly
egregious, it could be elevated to a
misdemeanor, punishable by a $1,000 fine
or 6 months in prison. This is a relatively
straightforward way to issue penalties for
ordinance violations, but it also does not
provide the City equal compensation for
the lost value.
• The Guide for Plant Appraisal was
created by the International Society of
Arboriculture to provide arborists with an
industry method to evaluate the financial
value of a tree. This method considers the
tree species, health condition, size (height
and DSH), location on the property, and
other factors in generating an appraisal.

Using this method, large, mature trees
are frequently evaluated to be worth
thousands to tens of thousands of dollars.

The high monetary value has the potential
to encourage tree preservation efforts
over removal, A variation of this method
would need to be considered in cases
when a tree has been removed and
not enough information is available to
complete the valuation. It should be noted
that updates to the guide may happen, and
as such, it is important to stipulate that all
appraisals are in line with the most current
version of the plant appraisal guide.
• Calculating environmental services
through a program like i-Tree Eco would
generate a value that considers most
of the same information as the Guide
for Plant Appraisal. The main difference
between the two is that i-Tree Eco only
calculates the replacement costs and
environmental values of the tree and does
not include its landscape value. If used to
determine a fine amount, it would provide
a relatively accurate cost for the City to
replace what was lost. Again, flexibility
in implementing this method would be
needed when not enough information is
available.

4.2.5 Tree Replacement
Whenever a tree is removed in the City, more
trees need to be planted to begin replacement of
the lost environmental services. Cities will often
arbitrarily assign replacement ratios of 1:1 or 2:1
when trees are removed without connecting the
standards to a larger city policy. Since La Mesa
does not have a tree protection ordinance, every
removed tree results in lost canopy cover that
has no mechanism to be recovered. As stated
in Section 2.2, City canopy cover is declining,
and it can take 30 to 40 years for a tree to reach
maturity and replace lost canopy. The impacts
of climate change are already felt through
increased temperatures and increased drought.

The need for canopy cover will increase as
climate change progresses, and the City will be
significantly behind in developing a canopy cover
to protect human health without preserving and
replacing trees. Not having a tree replacement
policy as part of tree protection ordinance is a
missed opportunity to advance the City towards

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reaching its goals for the urban forest, such as
increasing tree canopy cover.

Canopy Goal for Site. Tree replacement does
not have to be based on the removed tree but
rather directed toward City-wide and site-specific
canopy cover goals. The City could require a site
to maintain a canopy cover percent that aligns
with the City-wide goal. It could also enact sitespecific goals such as canopy cover targets for parking lots, business centers, residential
developments, open spaces, and urban infill
development. A benefit to this model is that
site-specific canopy goals do not require a
certain number of trees to be planted and allow
for more flexibility in what the City can accept
as mitigation. It is less specific for the City, and
developers and would require a thorough
analysis to determine if the plan meets the City
requirement.

DSH Replacement. This method states that
an equal amount of trunk diameter should be
planted to replace what was lost. For example,
the removal of an 8-inch DSH tree could be
replaced by eight– 1-inch DSH trees, two 4-inch
DSH trees, or any other variation thereof. The
concept supporting this practice is to replace
the wood that was lost. In practice, it can lead
to an excessive number of trees needing to be
replanted, little available space to plant them, or
resources to maintain them.

Canopy Replacement. Another method is
to base the number of replacement trees on
replacing the canopy of the removed tree over a
defined time-frame. Table 30 provides sample
formulas for computing the replacement ratio.

While the replacement ratio in this scenario is
still somewhat arbitrary, it has more justification
for what the ratios are intending to accomplish
as large trees will have more replacement
trees planted and smaller trees will have fewer
replacement trees planted.

Tree Container Size. Replacement ratios are
usually based on the standard tree container
size required to be planted by a city in the public
right-of-way. In some cases, the container size
is increased when available space limits the
number of trees that can be planted. As an
example, the replacement plan for a project may
require four 15-gallon size trees to be planted on
site, but there is only enough space for two trees.

In lieu of planting four 15-gallon trees, a city may
request two 24-inch box trees, or another larger
size.

4.3 Private Property Trees
Recommendations

1. Adopt a tree protection ordinance for
private property trees to reduce tree removals.

An effective ordinance should clearly define
the staff responsibilities, have a feasible
method for enforcement, define the trees that
are protected, and stipulate tree replacement
requirements.

2. Update the landscape plan review
process to require an arborist’s report by an
International Society of Arboriculture (ISA)
Certified Arborist for tree removals. The
arborist’s report should include a discussion of
why tree removal is required, an explanation
about why tree preservation is not feasible,
and guidelines to protect trees during
construction if trees are to be preserved
during site development. Since the City does
not have an arborist on staff, a third-party
Table 30. Replacement Ratios Based on Canopy
Size
Removal Tree Size
(feet)
Replacement
Ratio
0–30 2:1
31–50 4:1
51–70 8:1
70+ 12:1
Eucalyptus, Eucalyptus
consulting arborist could be required to
further review the report for its accuracy and
make an independent determination if tree
removal is justified.

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5. Planning
Setting

5.1.1 History of La Mesa
Like much of San Diego County, La Mesa
was originally inhabited by Native American
tribal groups. The Kumeyaay (also known
by the Spanish name Diegueño) ancestral
lands occupy most of San Diego County and
northern Baja California, from Escondido to
south of Ensenada, Mexico (Bugbee 2021).

Founded in 1869 and incorporated in 1912, the
City of La Mesa contains a rich architectural
and agricultural history that remains present
in the City’s character and small-town feel.

Natural springs in the area and the discovery
of gold in the nearby mountains attracted
early settlers and visitors to the area. In
the late 1800s, growth and expansion of La
Mesa was spurred by the San Diego Flume
Company’s construction of the flume line,
which transported water into the area, as
well as construction of the railroad spur line
from San Diego to East County. By 1890, rail
service was available from Lakeside to San
Diego, with a stop in the vicinity of present
day downtown La Mesa, known as the Allison
Springs Station. As the area grew in recognition
and population, the local economy diversified
to include agriculture and citrus crops, packing
warehouses, health resorts, and limited film
production studios.

By the time of the City’s incorporation in 1912,
the population had reached 700. Growth of
the City continued at a slow but steady pace,

5.1 Introduction
Historical view of La Mesa

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and by 1930 the population had reached
2,500 residents, and El Cajon Boulevard had
been developed as a key transportation route.

Although the City’s growth was dampened by
the Great Depression, World War II reignited
growth in the form of new residential tracts
and suburban commercial centers, eventually
reaching a population of 3,912 residents by
1940. Post-World War II, the City became one
of the fastest growing suburban cities in the
region, and by 1980, the City was built out to
accommodate 50,000+ residents.

During the post-World War II period, expanding
infrastructure and land annexations led
to substantial development of residential
tracts, new schools, and shopping centers to
support the growing population. Residential
neighborhoods sprang up along the University
Avenue and El Cajon Boulevard corridors, and
along Lake Murray Boulevard and Baltimore
Drive. Residential subdivision tracts were
developed in a modernistic ranch style,
consistent with other major residential
tracts in the San Diego region. Growth in
the area continued to give rise to residential
neighborhoods, and major transportation
corridors were developed in the 1950s
providing connectivity to the surrounding
region. Eventually, custom homes in hillside
areas and multifamily infill development in and
around established neighborhoods resulted
in a varying aesthetic throughout the City.

The connection to the Metropolitan Transit
Development light rail in the 1980s reignited
the City’s historic downtown and gave rise to
new commercial and mixed-use areas with
façades in the Beaux Arts, classical revival,
Spanish revival, streamline modern, and
modernistic styles (City of La Mesa 2012a).

Through much growth, La Mesa has
become home to an estimated population
of approximately 59,966 (DOF 2020), which
is anticipated to increase to approximately
77,780 by 2050 (SANDAG 2010). Today, La
Mesa, commonly referred to as “The Jewel of
the Hills,” is a suburban City with over 59,000
residents who appreciate the small-town
charm and historic business district on which
the City was founded. The City takes pride in
its tree-lined streets, walkable neighborhoods
with easy access to commercial and retail
areas, and friendly ambience (City of La Mesa
2021).

5.1.2 Historical Land Cover
Over time, the vegetation communities and
land cover in the City have been influenced
by the region’s climate, wildlife, and human
interference. The City of La Mesa is located
12 miles inland from the Pacific Ocean in an
ecological transition zone between the coast
and foothills and has a semi-arid, steppe
climate (Climate Data n.d.). A series of flat
geologic features known as marine terraces
occur within this transition zone (City of La
Mesa 2012a). Prior to European settlement, the
vegetation communities and land cover in the
area occupied by the City primarily consisted
of chaparral and shrub vegetation, with dense
riparian forests along major stream and
river corridors. (CNPS 2018). As with much of
Southern California, La Mesa is subject to hot,
dry summers and mild, wet winters; periodic
drought, flooding, and wildfires have further
defined the vegetation communities in the
area. In addition to these natural variables,
the landscape has been altered over time by
anthropogenic disturbances. For centuries,
Native Americans practiced prescriptive
burning to clear land, encourage the
succession of edible vegetation, and control
the accumulation of flammable material,
among other reasons, which left a mosaic
of vegetation-types, including unnaturally
large areas of converted grassland or prairie.

Agricultural practices introduced by European
settlers, such as ranching, livestock grazing,
and farming, and the introduction of nonnative species, further altered the vegetation communities in the area. Repeated burning
and agricultural production over years has
reduced the natural vegetation previously
found in the La Mesa landscape (Lightner
2013).

Following Spanish colonization, the land that
constitutes south La Mesa was primarily
used for livestock grazing (sheep and cattle).

Early settlement in the late 1800s and the
development of the railroad and the flume line
resulted in growth of the local citrus industry,
and 5- and 10-acre citrus orchards spread
throughout the landscape. The naturally flat
marine terraces, or “tablelands,” that underly
the City made for easily developable land, and
the first suburban subdivisions were present
in the City by the early 1900s (LMHS 2019).

Eventually, the development of residential
tracts, commercial areas, and infrastructure
(e.g., roads and rail) resulted in substantial
transformation of the landscape as the City
has grown along with the surrounding region.

Today, approximately 98% of the City is
developed with residential or commercial land
uses, and the City does not contain significant
areas of natural habitat (City of La Mesa 2012a).

5.2 City Development
and Land Use
Development in the City is steered by various
City planning and guidance documents (such
documents are further discussed below). In
particular, the General Plan Land Use and
Urban Design Element serves as a guide for
the anticipated growth in the City and the
ultimate pattern of development. According
to the General Plan Conservation and
Sustainability element, approximately 98%
of the City's land area has been developed
with residential and commercial land uses.

As such, it is anticipated that most future
development in the City will consist of infill
or redevelopment of underutilized sites.

Through the policy framework, programs
and goals outlined in the Land Use and
Urban Design Element, the City aims to make
land use decisions that benefit La Mesa’s
residents and neighborhoods and contribute
to a healthful, sustainable, and attractive City
(City of La Mesa 2012a).

5.2.1 Transportation Corridors
Regional access to the City is provided by
I-8, State Route (SR-) 94, and SR-125. The Bus stop with tree shade

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City is divided by SR-125 (north/south) and
I-8 (east/west). The transportation network
also includes two light-rail trolley lines. The
City’s local roads and travel corridors provide
residents with connectivity throughout the
City and to major transportation routes. La
Mesa takes pride in its tree-lined streets,
which contribute to the visual character of
the City (City of La Mesa 2021). As noted in
the Circulation Element of the General Plan,
the spatial arrangement and appearance of
the transportation system help define the
character of La Mesa and contribute to the
perceived quality of life in the community (City
of La Mesa 2012a). Not only are cities with welllandscaped roads perceived more positively, but studies have shown that inclusion of trees
and other landscaping in the streetscape
may impact route choice, reduce stress, and
increase safety on urban roadways (Wolf 2010).

Appropriately placed trees in the streetscape
can contribute to traffic calming. One study
found a significant drop in travel speeds (an
average decrease of approximately 3 miles
per hour) on roads where trees are present,
as well as an increased perception of safety
(Topp 1990). Other studies analyzing vehicle
accidents on urban roads have found that
vehicle crashes were reduced by as much as
67% on road segments with street trees and
traffic calming treatments as opposed to roads
without improvements (Dumbaugh 2005,
2006). Consequently, roads with street trees
and landscaping also increase pedestrian and
bicyclist safety by influencing safer driving
practices and by providing a buffer between
vehicles and other modes of travel if these
elements are appropriately placed.

Surveys previously conducted by the City
reveal that that residents desire a network of
mixed-use transportation corridors (City of La
Mesa 2012a).

5.2.2 Commercial Corridors
The City contains a mix of commercial uses
featuring suburban shopping centers, a
regional shopping center (Grossmont Center),
and a downtown “Village” centrally located
within the City and adjacent to the I-8 corridor.

As discussed in Section 2 of this UFMP, the
City’s commercial areas have been identified
as having lower canopy cover than other parts
of the City. While trees are present in the City’s
commercial areas, there are large swaths of
land covered by impervious surfaces (e.g.,
paved parking lots, roads, buildings). These
areas are largely dominated by palm species
that do not yield a high amount of canopy
cover or the other associated benefits and
services provided by trees. Canopy cover
could be increased in these areas by removing
concrete and asphalt to create new tree
planting locations and planting shade trees
instead of palms.

Studies have explored the psychosocial
response of shoppers to outdoor
environments in commercial areas, revealing
consistently positive associations between
streetscapes with trees and consumer
preferences, perceptions, and behavior.

Surveys conducted in cities of varying sizes
across the United States revealed that
shoppers positively associated commercial
areas with trees as having higher visual quality
and an improved sense of place. Shoppers
also indicated an increased willingness to drive
farther and pay for parking and, perhaps most
notable, a willingness to pay higher prices for
goods and services in consumer environments
with trees. Survey respondents indicated that
they would spend 9% to 12% more for goods
and services in commercial districts with a
high-quality tree canopy (Wolf 2005).

5.2.3 Waterways and
Stormwater Capture
La Mesa contains several natural waterways
and water bodies, as well as human-made
stormwater capture and conveyance systems.

The City is located within the San Diego
River, Sweetwater River, and Pueblo San
Diego watersheds. Each of these watersheds
pass through multiple jurisdictions and
eventually drain to the Pacific Ocean or the
San Diego Bay. The watershed drainages
consist of small local creeks and channelized
or pipe conveyances. Lake Murray is located
immediately northwest of the City, and Alvardo
Creek, Chollas Creek, and Spring Valley Creek
pass through the City. Other water bodies in
the City include Mount Helix Reservoir (i.e.,
Lake Helix) as well as an unnamed lake in the
eastern portion of the City. La Mesa does
not sit atop a groundwater basin; however,
the City is in proximity to the Mission Valley
Groundwater basin to the west, and the San
Diego River Valley Ground Water Basin and El
Cajon Groundwater Basin to the east (City of La
Mesa 2013b).

Maintaining surface and groundwater quality
is important for both human health and
environmental resources in and near the
City. The abundance of impervious surfaces
in urban areas creates an interconnected
network of hardscapes, which reduces
infiltration and groundwater recharge.

Additionally, high volumes of runoff may lead
to flooding, overloading the sewer system, and
contamination of surface and groundwater
resources (Berland et al. 2017). Under existing
conditions, groundwater quality in La Mesa is
low, and surface waters of Chollas Creek and
Alvarado Creek are listed as impaired water
bodies under Section 303(d) of the Clean Water
Act, due to the presence of pollutants from
urban runoff and other point and nonpoint
source pollution (City of La Mesa 2013b).

Trees can contribute to reducing stormwater
runoff and pollutants that reach local waters
by slowing and storing runoff, capturing
and storing rainfall, creating conditions
that promote infiltration of rainwater, and
absorbing and converting pollutants into less
harmful substances (EPA 2013).

Waterways and areas designed for stormwater
capture (e.g., bioswales) provide opportunities
for increasing the City’s canopy, while the
addition of street trees can contribute to
Tree-lined parking areas

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stormwater capture along roadways.

5.2.4 Parks and Open Space
La Mesa is largely built out and does not
contain extensive open space areas with
just 2% of the City’s land area remaining
undeveloped (City of La Mesa 2012a). The
remaining natural open space areas in the
City provide visual relief, habitat, cooling
benefits and many other benefits to the
otherwise urbanized and suburbanized
landscape. Natural landforms such as Mount
Nebo, hillsides, canyons and mesas define the
geography of the City and contribute to the
character of La Mesa. Parks and recreational
areas provide opportunities for citizens to
engage in outdoor recreation and scenic
enjoyment, while also providing important
canopy cover. Figure RO-1 of the City’s General
Plan identifies the parks, open space, and
recreational resources throughout the City.

The City contains 14 public parks, 3 designated
recreational amenities (Walkway of the Stairs,
Mount Nebo Stairs, and Train Depot), and 2
designated open space areas in the southern
portion of the City. The largest parks within
the City include Harry Griffen Park, a regional
park that is 53 acres in size, and MacArthur
Park, a community park that is over 22 acres in
Table 31. Percent of canopy cover per park.

Park Name Canopy Cover Percent within Park
Sports Fields/Courts/Other Facilities? (that could
impact canopy cover)
Aztec Park 24.4% No
Briercrest Park 14.3% No
Collier Park 25.7% Yes; tennis and pickleball courts
Harry Griffen Park 17% No
Highwood Park 29.1% No
Jackson Park 21% No
La Mesita Park (excluding Junior Seau
Sports Complex)

16.6% No
MacArthur Park 11.5% Yes; pool, baseball field, community center, recreation center, historic structures
Mission Trails Regional Park (analysis
accounts for <1 acre of park within City
limits)

15.7% No
Northmont Park 33% Yes; volleyball court
Porter Park 18.4% Yes; fitness plaza
Rolando Park 15.2% Yes; baseball fields
Sunset Park 12.8% Yes; multipurpose sports field, basketball court Sunshine Park 9.6% Yes; multipurpose sports field
Vista La Mesa Park 7.8% Yes; Little League field
During and after a storm event
storm
drain
wastewater
treatment
infiltration
recharge
runoff
Trees slow water down
increasing potential for
groundwater recharge
Trees Divert Stormwater Runoff
groundwater
aved surfaces increase
runoff, pollution, and
waste of water resources

112 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 113 5 Planning Setting
size (City of La Mesa 2012a). While trees within
parks are an important part of the City’s
urban forest and contribute to the character of
La Mesa’s neighborhoods, canopy cover within
parks comprises approximately 3.2% of the
City’s total canopy cover, as presented in Table
31, Canopy Cover in City Parks. As detailed
in Table 31, on an individual level some City
parks have high canopy cover within the park
space (Northmont Park has approximately 33%
canopy cover), while others are relatively low
(Sunshine Park has approximately 9.6% canopy
cover). Opportunities to increase canopy cover
in the City may arise as the City plans for park
improvement projects or development of new
parks, such as the vacant property located
at the northwest intersection of Waite Drive
and Murray Hill Road. However, the facilities
available at parks must be considered when
setting canopy cover goals for individual
parks, such as the presence of sports fields
that preclude the presence of trees in some
locations. As such, canopy goals for parks will
vary by park location.

5.3 City Planning Documents

5.3.1 Climate Action Plan (2018)
The City’s CAP was adopted in March 2018
and provides a long-range plan to reduce GHG
emissions in La Mesa in order to support the
state’s efforts under Executive Order S-3-05,
Senate Bill 32, and Assembly Bill 32 and to
mitigate climate-related impacts. The CAP
describes the 2010 GHG emissions baseline
and forecasted emissions for 2020 and 2035
and identifies strategies and actions to reduce
emissions. Consistent with state goals and
guidance, as well as a mitigation measure
outlined in the City’s General Plan, the City
is seeking to reduce GHG emissions to 15%
below 2010 levels by 2020 and 53% below the
2010 levels by 2035 (City of La Mesa 2018).

Chapter 3, Emissions Reductions Measures,
of the CAP includes emissions reduction
strategies, including goals, measures,
and action steps, to reduce the City’s
GHG emissions. Reduction strategies are
categorized by sector: energy, transportation
and land use, water, solid waste, and green
infrastructure. Trees and urban forestry are
central to three reduction strategies in two of
the sectors (energy and green infrastructure),
as listed and further discussed below. The CAP
is set to be updated in 2023 and may consist
of updated measures and reduction targets.

The following reduction strategies are outlined
in the existing CAP, but may be refined
during the subsequent CAP update. The
recommendations outlined in this UFMP will be
referenced during the CAP update process.

ENERGY REDUCTION STRATEGIES
• E-2, Shade Tree Program. Develop a shade
tree program to require developers and
property owners to plant shade trees.

With implementation of Reduction Strategy
E-2, through the development review process,
the City will require new development and
renovation where feasible to plant shade
trees. The CAP accurately discusses the many
environmental services provided by trees
and indicates that the City is a designated
Tree City USA and is part of the County of
San Diego’s Tree Inventory program. The total
GHG emission reduction potential of the E-2
Reduction Strategy is <1 metric ton carbon
dioxide equivalent per year (MT CO2e/yr) by
2020 and 10 MT CO2e/yr by 2035. The CAP
makes the following commitments related to
Reduction Strategy E-2:
• The City will conduct a tree canopy analysis
to better understand the services currently
provided by La Mesa’s urban forest and
how to expand the existing tree canopy.
• The City will expand its City-wide urban
forestry program
• The services of a regional urban forester
will be engaged (to be shared with
neighboring municipalities)
Implementation Table E-2 outlines the
implementation strategies for the shade
tree program and progress indicators, which
include planting 250 new shade trees from
2010 to 2020, and 1,575 new shade trees from
2010 to 2035.

Appendix B-4 of the CAP provides the cost
estimates for implementation of the shade tree
program.

RELATIONSHIP TO THE UFMP
Appendix B-4 of the CAP provides the cost
estimates for implementation of the shade tree
program.

Reduction strategy E-2 requires developers
and property owners to plant trees. The CAP
includes a progress indicator of planting 250
new shade trees from 2010 to 2020, and
1,575 new shade trees from 2010 to 2035.

An implementation and tracking program
should be established so calculated GHG
reductions that would be achieved by tree
plantings can be reported in future CAP
updates or implementation plans. As outlined
in Implementation Table E-2 in the CAP and
recommended in this UFMP, ordinances
that include landscaping requirements and
tree protection measures would help to
achieve the goals of this CAP strategy. An
ordinance that establishes minimum tree
planting requirements for new development
and redevelopment projects should include
minimum shading requirements and canopy
goals to instigate new tree plantings and
reduce urban heat islands. Further, a tree
protection and maintenance ordinance for
public and private trees would help to preserve
existing trees to ensure that canopy cover is
continuously increasing.

Targeted outreach to private property owners
explaining the benefits of trees. Further
defining these partnerships and outreach
efforts would provide the City with a clear
path forward in implementing this reduction
strategy. Additionally, a regional urban forester,
shared with neighboring jurisdictions, has not
yet been established. As discussed throughout
this UFMP, management of the urban forest
with input from an arborist or urban forester
would help to ensure that urban forestry
best management practices are appropriately
applied.

GREEN INFRASTRUCTURE

REDUCTION STRATEGIES
• GI-1, Urban Forest Master Plan
• GI-2, Expanded Urban Forestry Program
The green infrastructure (GI) strategy section
of the CAP discusses the urban forest as one
component of the City’s green infrastructure
network (other components include parks,
landscaped medians and parkways, and
natural stormwater-absorbing landscapes).

The strategies outlined in this section include
GI-1, Urban Forest Master Plan, and GI-2,
Expanded Urban Forestry Program. The CAP
discusses the many environmental services
provided by the urban forest, including shade,
reduced urban heat island effect, reduced
energy use, natural stormwater management,
wildlife habitat, improved air quality, carbon
sequestration, aesthetic improvements and
community pride, increased property values,
noise reduction, stormwater management,
wildlife habitat, and privacy/screening. The
total GHG emission reduction potential for
GI-1 is 50 MT CO2e/yr by 2020, and the total
GHG emission reduction potential for GI-2
is 6,300 MT CO2e/yr by 2035. These GHG
reduction calculations are based on the

114 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 115 5 Planning Setting
progress indicator for GI-1 of planting 500 new
net trees in the community from 2015 onward,
which was achieved in 2021, and the progress
indicator for GI-2 of increasing tree canopy to
2,450 acres by 2035.

With implementation of reduction strategy
GI-1, the City will support natural carbon
sequestration opportunities through
continued development and maintenance of
the urban forest. The CAP makes the following
commitments related to Reduction Strategy
GI-1:
• The City will partner with existing
neighborhood groups and organizations to
encourage additional tree planting within
the community.
• The City will host an educational workshop
to assist residents with species selection
and planting guidance to maximize
building shading and minimize damage to
underground utilities and pavement.
• The City will also continue to implement
its existing landscaping requirements to
integrate shading within parking lots to
reduce local urban heat island impacts,
as well as implement landscaping
requirements at municipal facilities.
• Staff will develop an urban forest master
plan or participate in future regional
efforts to develop a plan. Such plans will
include the potential long-term impacts
associated with climate change when
making recommendations on suitable tree
species and planting strategies, particularly
watering requirements to maintain a
healthy tree network.

With implementation of reduction strategy
GI-2, the City will increase La Mesa’s urban
forest canopy coverage to reduce impacts of
the heat island effect, improve stormwater
management, provide additional habitat, and
maximize carbon sequestration. An Urban
Tree Canopy Assessment was prepared for
the San Diego region, which concluded that
La Mesa has an existing urban forest canopy
that covers 18% of the City (or 1,050 acres).

The assessment revealed a potential canopy
coverage of 66% in the region. This measure
assumes La Mesa can achieve 33% coverage
by 2035, for a total urban forest of 2,450
acres. The CAP assumes that half of the new
urban forest coverage could be achieved by
2035. Appendix B of the CAP provides the
methodology for these calculations.

REDUCTION STRATEGY GI-1
This reduction strategy indicates that the
City will continue to implement its existing
landscaping requirements within parking lots
to reduce local urban heat island impacts.

The CAP does not provide details regarding
the parking lot landscaping requirements and
whether they include requirements for trees,
or where these requirements are provided
(Section 24.04, Parking, of the Municipal
Code does not contain any requirements
for tree planting in parking lots or parking
areas). The City’s landscape standards
(discussed in Section 4.1.2) require planting
one tree per 500 square feet of landscaping.

However, these standards do not contain
specific requirements related to parking lots.

Clarification regarding the parking lot shading
requirements is needed to successfully
implement this strategy. Landscaping
requirements should be established through
a codified ordinance, including minimum tree
planting requirements by land use type, and
development intensity would help implement
this reduction strategy and mitigate heat
islands in key areas, such as parking lots
and commercial corridors with extensive
hardscape.

The progress indicator for reduction strategy
GI-1 includes planting 500 net new trees
annually from 2015 onward. Tree plantings and
associated GHG reductions can be tracked and
reported in future annual reports for the CAP
to track progress toward GHG reduction goals.

The CAP includes a sample plant palette,
including lemon bottlebrush, Brazilian pepper,
Victorian box, sweetgum, and carob. Given the
climate conditions of the City and the need to
increase canopy cover, the City can reference
the recommended tree species list provided
in this UFMP to supplement this plant palette
and create a more resilient urban forest. Thus,
tree planting goals, policies, maintenance
requirements, and recommended species
that are identified in this UFMP can also
be referenced in future CAP updates and
implementation plans.

REDUCTION STRATEGY GI-2
Reduction strategy GI-2 focuses on expanding
the urban forest and canopy cover to achieve
GHG reductions. The UFMP provides additional
data such as available planting locations that
are critical to determining the potential for
increasing canopy cover. The methodology
used in the CAP may warrant further City
review to determine if the calculations used to
determine potential canopy cover accurately
incorporate urban forest management
planning principles and represent achievable
goals. The calculations for the potential
canopy cover in La Mesa should be assessed
in relation to the canopy analysis in the UFMP.

Specifically, the CAP stated potential canopy
cover of 66% in the region equates to 33%
potential coverage in the City by achieving a
total canopy cover of 2,450 acres. The UFMP
canopy cover calculations and methodology
can be used to inform the City’s review of the
CAP canopy cover projections.

5.3.2 Urban Trails Mobility
Action Plan (2016)
The Urban Trails Mobility Action Plan (UTMAP),
adopted in 2016, identifies 9.5 miles of
existing urban trail routes (sidewalks) that
connect high-priority neighborhoods with
key community destinations such as parks
and recreation, hospitals, and local retail in
La Mesa, and provides recommendations
and guidelines for establishing proposed
new routes and improvements to existing
routes (City of La Mesa 2016). The UTMAP
incorporates standards outlined in the
City’s Parks Master Plan and the Bicycle
Facilities and Alternative Transportation Plan.

Recognizing the significant health, economic,
environmental, and social benefits provided
by a reliable active transportation network,
the UTMAP identifies goals and objectives
to improve the City’s active transportation
network, one of which mentions trees:
• Objective 2.0 - Create pedestrian
environments that encourage walking
through the use of public art, street trees,
furnishings and other amenities. Ensure
a positive walking environment by making
the pedestrian feel protected, comfortable,
and connected with the environment and
the City.

Despite the low number of policies and
objectives that explicitly include trees, the
UTMAP discusses trees throughout the
document. The presence of street trees or
opportunities for planting were included in
the data collection process when examining
urban trail routes, and Figure 4-3 in the
UTMAP identifies where opportunities for
street trees exist along the routes. The
UTMAP also includes an implementation
guide which presents strategies to facilitate
implementation of the UTMAP and its
recommended projects. Opportunity 2, Utility
Undergrounding Program, discusses the
opportunity for the City to partner with San
Diego Gas and Electric (SDG&E) to improve La
Mesa’s streets, and upon development of an
urban forestry program, allow SDG&E to plant

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trees in parkway strips, assuming the adjacent
property owner would agree to maintain
the trees. Public input was gathered during
preparation of the UTMAP to help identify
locations where improvements to the active
transportation network are needed. Public
input results are provided in Appendix C of the
UTMAP. Trees were mentioned six times during
the public input process.

Chapter 5 of the UTMAP provides a Street
Design Toolkit, which is a guide that can
be used to build a desirable street, urban
trail, and attractive public realm. The Design
Toolkit includes four sections that describe
street design elements and examples of
improvements that could be implemented. The
Urban Forestry Element recommends planting
drought-tolerant, litter-free, upright trees
with canopies that provide shade. The Urban
Runoff Element recommends the use and/or
installation of infiltration basins to capture and
filter stormwater and runoff, including street
trees installed with a tree grate. The Urban
Open Space Element recommends installing
enhanced concrete walkways, wayfinding
signage, and trees that provide shade within
the pedestrian and parkway zones.

The UTMAP proposed urban trails, and
projects were prioritized based on a scoring
system, with points earned through various
ranking criteria. The scores range from 3
points, 2 points, and 1 point, representing
high, moderate, and low scores. High scores
indicate trails that could be most easily
implemented into the urban trails network due
to fewer barriers to improvement. The cost of
implementing trail improvements was included
during the prioritization process, which
factored in the cost to install trees (priced at
$250 per 15-gallon, 24-inch box tree). “Shade
provided by street trees” was included as a
trail experience ranking criteria, with scores
based on the length of trail with street trees
out of the trail corridor length, demonstrating
the importance of street trees to the urban
trail experience. Trails that received the lowest
score (1 point) for this criterion (in other words,
trails the lowest percentage of trail with trees)
include the following:
• University Avenue Trail
• Junior High Drive Trail
• Center Street/Spring Street Trail
• Helix High Trail
• 70th Street Trail
• Massachusetts Avenue Trail
• Parks Avenue Trail
• Jackson Drive Trail
• Alvarado Creek Channel Trail
• La Mesa Boulevard Trail
• Severin Drive Trail
• Baltimore Drive Trail
• Lake Murray Boulevard Trail

RELATIONSHIP TO THE UFMP
The UTMAP accurately considers trees a critical
part of the walkability of the City’s urban
trails. This UFMP supports the UTMAP’s goals
to increase tree cover along the City’s urban
trails and can be used as a reference when
implementing trail improvement projects.

Additionally, planting trees to improve urban
trails will aid in increasing canopy cover in
critical locations identified in the UTMAP. The
trails identified in the UTMAP as most in need
of trees have been included as tree planting
opportunity areas in Figure 6, Priority and
Opportunity Areas.

5.3.3 Bicycle Facilities and
Alternative Transportation Plan
(2012)
The Bicycle Facilities Plan and Alternative
Transportation Plan identifies bicycle and
Example of an urban trail pedestrian needs throughout the City,

118 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 119 5 Planning Setting
reviews current conditions, examines optional
improvements, and prioritizes implementation
strategies with viable funding sources.

The Plan contains goals, objectives, and
policies for improving bicycle and pedestrian
infrastructure (City of La Mesa 2012b). One
objective and one policy aimed at improving
pedestrian facilities mention trees:
• Objective 2 - Create pedestrian
environments that encourage walking
through the use of public art, street trees,
furnishings and other amenities. Assure
a positive walking environment by making
the pedestrian feel protected, comfortable
and connected with the environment and
the city.
• Policy 2.5 - The City will encourage
pedestrian public improvement projects
such as street trees, lighting, directional
signs and public art.

While only one objective and one policy
mention trees, the Plan further discusses
trees throughout the document. The Plan
discusses various walkability issues, safety
issues along roads (major arterials and smaller
local/residential roads), and issues at bus
stops, including the lack of buffers between
pedestrian and vehicles. The Plan proposes
possible solutions and guidelines, many of
which involve trees, such as trees for traffic
calming and parkway planting buffers between
cars and pedestrians, which would help to
reduce collisions and provide some protection
and increase comfort for pedestrians, and
trees to provide shade and aesthetic benefits.

Development of the Plan considered public
input through online surveys and workshops.

Trees were mentioned five times in the survey
comments, four of which requested more trees
along sidewalks and streets.

RELATIONSHIP TO THE UFMP
The Bicycle Facilities and Alternative
Transportation Plan accurately discusses the
added safety benefit that trees provide for
traffic calming or when planted as a buffer
between vehicles and bicycles or pedestrians.

This UFMP supports the Bicycle Facilities and
Alternative Transportation Plan by providing
tree planting guidance and maintenance
standards that can be referenced as active
transportation projects are implemented
throughout the City.

5.3.4 Parks Master Plan (2012)
The Parks Master Plan identifies park and open
space improvements that will address the
needs of La Mesa’s growing population, and
creates a roadmap for upgrades, expansions,
and potential additions to the City of La Mesa’s
parks system (City of La Mesa 2012c). The
purpose of the Parks Master Plan is to ensure
the City maintains a wide range of different
types of parks distributed throughout the
City, and to ensure that parks are accessible
by walking or biking from residential areas. It
includes an overview of the existing parks and
policies, identifies deficiencies in parks and
access issues, and makes recommendations
to improve park facilities and meet goals
regarding the quantity, distribution, and quality
of parks in the City. The Parks Master Plan
does not contain any policies or objectives
that relate specifically to trees. However, the
plan identifies City parks that have trees, and
makes the recommendations that street trees
should be incorporated into the City’s urban
trail loops (which, as previously discussed, is
a goal of the 2016 Urban Trails Mobility Action
Plan). The plan discusses the environmental
benefits that trees would provide on the urban
trail loops, such as enhanced visual quality,
improved pedestrian experience and safety,
reduced traffic speeds, carbon sequestration,
reduced urban heat island effects through
shading, and water quality improvements. The
plan gathered public opinion through surveys;
trees were mentioned 10 times by survey
respondents, specifically for their benefits to
the community and the need for more trees.

RELATIONSHIP TO THE UFMP
The tree planting standards, species
recommendations, policies, and guidance
outlined in this UFMP can be referenced when
implementing the parks projects to achieve
healthy trees in proposed park locations and
urban trails. As discussed in Section 5.2.4
canopy cover within City parks constitutes

3.2% of the City’s total canopy. Based on the
canopy cover calculations for individual parks,
the City can increase canopy cover in some
Bike path with tree buffer
Park trees provide 3.2% of La Mesa's total canopy cover

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park locations. Setting canopy cover goals for
new park development and park improvement
projects would help guide this increase.

5.3.5 Walkability Plan (2006)
The purpose of the City’s Walkability Plan is
to serve as a community-based vision and
action plan to make La Mesa a more walkable
community. The Walkability Plan also aims
to progress the City toward achieving the
General Plan vision of creating a community
in which residents can commute without a
motor vehicle (City of La Mesa 2006). There
are multiple benefits associated with walkable
communities, including improved health,
cleaner air quality, an established sense of
community, and improved community safety.

Of the 14 “Visions for a Walkable La Mesa”
listed in the Walkability Plan, two relate to trees
and are included below:
• Trees and grass in the landscape strips
• Flower baskets hanging from trees and
phone poles that always have flowers in
them
The Walkability Plan expands on these visions
throughout the document. For instance, the
goals and visions for the Downtown Village
Specific Plan area include “streets that would
be heavily landscaped with trees and would
include pedestrian-friendly features.”
Chapter 4, Recommended Improvements,
of the Walkability Plan contains six
recommendations related to trees in various
aspects of City planning, including non-hillside
local streets, access management, and school
areas. These recommendations are listed
below.

NON-HILLSIDE LOCAL STREETS
• Although most of La Mesa is built out,
there will be times when new non-hillside
local streets are needed. This [picture
of a] typical section [of sidewalk] is the
preferred design for safety and value.

Street details include a double canopy of
trees, 5 foot wide sidewalks, 6 foot planter
strips, two 7 foot parking lanes and one
14 foot travel lane (yield lane). This design
helps hold speeds to 20-25 mph, and is
considered a very safe design. This design
maximizes on-street parking. To provide
access to fire equipment, curb extensions
(with hydrants) or double driveways can
be used. Streets this narrow need to be
part of a well connected street system that
allows multiple points of access.
• Sidewalks and trees: The combination
of 5-foot sidewalks, trees and planters
create comfortable walking space, add to
property values, and increases the green
qualities and needs of neighborhood
streets. Curb extensions on corners
reduce entry speeds, while preserving
access.

ACCESS MANAGEMENT
• Medians increase safety. Studies now show
that over half of all fatalities and injury
producing crashes can be eliminated with
well-designed medians. In some cases
reductions are as high as 90%. Trees in
medians may reduce crashes even more
(Palo Alto study by Reid Ewing).
• Sight Lines. To maintain sight triangles
and sight lines, guidance is needed for
the placement of landscaping and trees.

Generally native, xeriscape plant materials
and slow growth shrubs are preferred.

They should be kept trimmed to 2 feet.

Trees with more than a 6 inch caliper
should be placed back from intersections
50 or more feet, and spaced to allow
natural canopies to evolve. Trees should
be under trimmed to 7 feet, thus helping
assure adequate sight lines.

SCHOOL AREAS
• Recommended features of school
crossings include:
• Use of curb extensions, especially if low
(2.0 foot) ground cover and tall undercut
trees are used, increases motorists’
awareness of the choker effect, and
further reduces their tendency to speed.

Excess driveway widths are also reduced,
preferably with an in-only and outonly pattern between two appropriate driveways.
• Appendix A of the Walkability Plan
describes walkability concepts and
highlights the role of trees in improving
pedestrian safety, reducing the urban
heat island effect and makes the following
recommendations related to trees.

WALKABILITY CONCEPTS
• Properly located street trees are not frills,
fluff nor safety hazards. Instead they
are aids in traffic calming, a means of Trees benefit pedestrian routes by providing shade, increased safety, and aesthetic appeal

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purifying air and a cooling mechanism. La
Mesa should add urban street trees on
all significant corridors. Trees should be
set back 4.0 feet from travel lanes. Use
of bike lanes creates more border width,
allowing closer spacing. Minimum setback
of all street furniture should be 18–24
inches. Trees are normally spaced 30–50
feet apart. In urban walkways trees often
require specially prepared tree wells.
• One of the best ways to bring back night
life to a town center is to provide adequate
pedestrian scale lighting. Quality town
center lighting includes three light sources:
(1) pedestrian scale lamps (preferably
down lighting to preserve the night sky),
(2) Theme or ambient lighting on buildings,
in trees or other featured lighting, and (3)
interior lights on timer systems that create
a warm glow from inside the buildings
Lastly, Appendix B of the Walkability Plan
contains the public participation results. Input
was gathered from La Mesa residents to help
develop the Walkability Plan. During the public
workshops, trees were mentioned seven
times during discussions regarding the most
important things to make La Mesa a walkable
community.

RELATIONSHIP TO THE UFMP
The Walkability Plan accurately discusses the
environmental services provided by trees and
defines some parameters for tree planting,
such as tree placement (e.g., setbacks,
spacing) and the need for tree maintenance.

The most meaningful discussion of trees is
contained in Appendix A, Walkability Concepts.

In addition to providing shade and cooler
temperatures along walkways, studies have
shown that properly placed trees can help to
reduce vehicle speeds and accidents, increase
the perceived safety of roads, and increase
pedestrian safety by creating a buffer between
vehicles and pedestrians (Wolf 2010).

5.3.6 General Plan (2012)
The City of La Mesa General Plan, last updated
in 2012, guides land use and development
decisions in the City and aims to balance
the needs of the existing community and
anticipated growth. The 2012 La Mesa General
Plan includes the seven state-required
elements (land use, circulation, open space,
noise, conservation, public safety, and housing)
as well as three additional elements: historic
preservation, public services and facilities, and
health and wellness. The General Plan also
addresses urban design (Land Use Element),
sustainability (Conservation Element), and
recreation (Open Space Element). Compared
to the previous iteration of the General Plan,
the 2012 La Mesa General Plan incorporates
issues of sustainability, climate change,
complete streets, water conservation, and
wellness to address these pressing issues
faced by the City currently (City of La Mesa
2012a). As the “Centennial” General Plan, the
2012 General Plan provides a review of the
City’s previous 100 years since its founding in
1912 and serves as planning document for the
next 20 years of the City’s development.

A review of the City’s General Plan revealed
five policies that directly relate to trees and
management of the City’s urban forest. The
policies listed below are directly related to the
City’s trees and urban forest (City of La Mesa
2012a).

LAND USE AND URBAN DESIGN

ELEMENT
• Policy LU-3.1.6: Provide new site
amenities, such as outdoor seating areas,
bike racks, landscaping, and street trees as
development occurs.
• Policy LU-6.1.5: Development of hillside
and hilltop parcels will be evaluated
relative to topographic features, scenic
resources, sensitive, natural habitats and
landscaping, including mature stands of
trees, to determine if these features should
be retained.
• Policy UD-3.1.5: Increase the amount of
foliage, especially street trees, for aesthetic
reasons and to provide shade, cooling,
habitats, air quality benefits, and visual
continuity.

CONSERVATION AND SUSTAINABILITY

ELEMENT
• Policy CS-1.1.3: Preserve existing trees
where appropriate and require planting of
new trees in conjunction with public and
private developments.

PUBLIC SERVICES AND FACILITIES
• Policy PSF-6.3.3: Maintenance will be
performed on street trees, curbs, gutters,
sidewalks, pedestrian ramps, signage,
striping, and roadway surfaces.

In addition to these tree-related policies,
the General Plan also contains 11 policies
that relate to landscaping. The tree- and
landscaping- related goals, policies, and
programs are found across six General
Plan Elements, demonstrating the impact
of trees and the urban forest in multiple
areas of City planning. Other aspects of the
General Plan address trees indirectly through
goals, policies, and programs related to
environmental services offered by an urban
forest. For example, the Land Use and Urban
Design Element discusses climate change
legislation and sustainability, noting that the
City has consistently been named a Tree City
USA since 1980 and recognizing that trees
consume carbon dioxide, reduce energy use,
reduce the urban heat island effect, conserve
water, and provide habitat. The Conservation
and Sustainability Element includes a similar
Table 32. Municipal Code Policies Related to Trees
Theme Municipal Code Chapter or Section
City Maintenance Activities
Section 9.06.010. Director of Public Works - Responsibility Chapter 10.40 Weed, Rubbish and Nuisance Abatement
Section 12.52.060 Visibility obstructions
Section 18.16.030 Permits for street work
Property Owner/Lessee
Maintenance Activities
Chapter 24.05 Residential Zones and Development Standards Chapter 24.07 Industrial Zone
Section 26.09.180 Trimming of Trees
Planning activities Chapter 22.04 Minor Subdivisions
Section 24.02.037 Tree policy manual
Overlay Zones
Chapter 24.09 Scenic Preservation Overlay Zone
Chapter 24.10 Brier Tract Overlay Zone
Chapter 24.17 Bowling Green Overlay Zone
Chapter 24.18 Mixed Use Overlay Zone
Prohibited activities Chapter 9.08 Rules Governing Park and Recreation Areas

124 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 125 5 Planning Setting
discussion and indicates the Development
Advisory Board serves as the City’s Tree Board
and reviews and updates the City’s Tree Policy
Manual. Additionally, trees are identified as
contributing to the community image as “minor
landmarks” or “scenic vistas” in Figure LD-10,
Community Image, of the Conservation and
Sustainability Element. The Circulation Element
also recognizes the aesthetic benefit provided
by landscaping in the streetscape. The
Circulation Element and Health and Wellness
Element both discuss the added safety for
bicyclists and pedestrians when landscaping
is incorporated into pedestrian and bicycle
infrastructure, while the Public Services and
Facilities Element discusses the importance
of street tree maintenance. The Health and
Wellness Element discusses the potential for
the City to facilitate the availability of fresh and
healthy foods through urban agriculture and
fruit trees (private and public).

RELATIONSHIP TO THE UFMP
The General Plan accurately discusses the
benefits and services provided by trees and
contains policies related to the planting,
maintenance, and preservation of trees in the
City. The UFMP will support implementation
of the tree related policies in the General
Plan. Policy UD-3.1.5 calls for “increasing the
foliage, especially street trees, in the City.”
This policy will be supplemented by vacant
tree planting sites identified in this UFMP as
well as the canopy cover goals. Strategies for
implementing this policy and increasing canopy
cover include adopting an ordinance that
outlines requirements related to tree removal
and tree replacement in development and
redevelopment projects, such as a adopting a
tree replacement mitigation ratio of at least 1:1
and minimum shade requirements for specific
project types. Mitigation strategies can also
involve establishing an in-lieu fee program to
provide a revenue stream for the City’s tree
program. Policy PSF-6.3.3 calls for maintenance
of street trees. The maintenance standards,
recommendations, and policies outlined in
the UFMP will support implementation of this
policy by providing guidance for street tree
maintenance.

As the 2012 iteration of the General Plan
emphasizes the issues of sustainability, climate
change, complete streets, water conservation,
and wellness, the UFMP goals and strategies
to expand tree canopy cover and shade
and establish a more resilient urban forest
supports the General Plan in addressing these
issues. As previously discussed in Section 2 of
this UFMP, trees provide many environmental
services and benefits that can help advance
the City’s goals toward a more sustainable,
resilient La Mesa. During subsequent updates
to the General Plan, the City can reference
the UFMP and should consider advancing
the UFMP through the adoption of General
Plan policies and implementation strategies
that reflect the goals, recommendations, and
strategies outlined in this UFMP.

5.3.7 Municipal Code
The La Mesa Municipal Code holds the official
policies, ordinances and laws adopted by the
City. The municipal code outlines 15 policies
and guidelines related to management and
maintenance of the City’s tree population,
permitted actions related to trees/tree
removal, and expectations for property
owners. Table 32 presents the sections of the
municipal code that contain policies related
to trees and organizes these sections by the
general theme addressed in these sections.

RELATIONSHIP TO THE UFMP
The Municipal Code could include guidance
on the public and private protected tree
ordinance discussed in this UFMP once
adopted. The Municipal Code does not
contain City-wide policies related to tree
planting requirements in parking lots, along
roads, or within commercial or residential
lots, with the exception of the overlay zones
(24.09 Scenic Preservation Overlay Zone
requires replacement of specimen trees and
a landscaping plan to be submitted with
building permits detailing the removal and
replacement of trees; 24.10 Brier Tract Overlay
Zone requires four trees on every residential
lot; 24.17 Bowling Green Overlay Zone requires
three, 36-inch boxed trees to be planted on
every single-family residential lot; and 24.18
Mixed Use Overlay Zone requires that 25% of
the common space shall be planted, including
trees, shrubs, and gardens). The tree planting,
maintenance, and protection policies and
recommendations discussed throughout this
UFMP and outlined in the Strategic Plan should
be adopted as ordinances in the next update
of the Municipal Code. Codifying meaningful
tree ordinances will create a regulatory
framework for maintaining the urban forest.

Such ordinances must be implementable and
enforceable, which may require additional
funding for the urban forest

5.3.8 Downtown Village
Specific Plan (1990)
The Downtown Village Specific Plan provides
direction for the Downtown Village of La
Mesa. Adopted in 1990, the Specific Plan sets
a planning horizon of 20 years. The goals and
policies outlined in the Specific Plan remain
pertinent to the vision for the City’s Downtown
Village. The plan area consists of 161 acres
plus street rights-of-way in the downtown
commercial area, Civic Center, and surrounding
residential neighborhoods (City of La Mesa
1990). The Specific Plan contains multiple
recommendations, goals, and proposed
landscaping elements related to trees, as
described below.
• A “dramatic urban forest landscape” with
a “thick density of canopy trees” should
be added over the entire Civic Center,
including parking lots.
• Spring Street should be lined with a
“dramatic row of Mexican Fan Palms”
on both sides of the street; landscaped
medians where possible; and dense
canopy trees at the freeway entrance.
• The Downtown Village would emphasize
the pedestrian. A thousand trees would be
added to the streets, located at the curb
between the travel way and sidewalks to
create pleasant pedestrian paths
• Goal 16. Trees – Trees – Trees: An
appropriate design theme for the
Downtown Village is one of streets heavily
landscaped with street trees. Parking
areas should also be heavily landscaped,
with cars visually screen to emphasize the
pedestrian/landscape/architecture images,
i.e., “parking parks”
The Specific Plan contains multiple policies
related to implementing an urban forest in
the Downtown Village. These policies specify
streets and street segments where trees
should be planted, as well as tree planting
locations within the streetscape, and tree
spacing, emphasizing the desire for large trees
and pedestrian scale development.

Section IV, Implementation, Section 8,
Public Improvements, describes the street
improvements and tree planting program
that should be implemented in the Downtown
Village. Figure 7 of the Downtown Specific Plan
depicts priority areas for street tree planting,
and the implementation plan proposed 813
new street trees in the Downtown Village.

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RELATIONSHIP TO THE UFMP
The Downtown Village Specific Plan contains
multiple goals, policies, and recommendations
related to trees, exemplifying the City’s desire
for a robust urban forest in its Downtown
Village. Metrics for tracking implementation
of the proposed street tree program are not
provided. While the Specific Plan emphasizes
the desire for large trees and an expanded
canopy, it also suggests the planting of
Mexican Fan Palms in multiple locations.

Palm species do not have large crowns to
provide ample shade, nor do they contribute
significantly to the canopy cover. Further,
palm species do not provide the same level
of benefits and services as other tree species
(see Section 2.5.5, Importance Value, of this
UFMP). Rather, the City can better achieve this
goal by prioritizing planting of large canopy
trees included in the recommended species
list.

5.3.9 Livable La Mesa Age
Friendly Action Plan (2018)
The Livable La Mesa Age Friendly Action Plan was
developed through AARP’s Livable Communities
Initiative, with support from The San Diego
Foundation Age-Friendly Communities Program
in fall 2018. The Action Plan aims to help make
La Mesa a more livable community for all ages
and, in particular, plan for and improve the health
and quality of life of older adults in La Mesa. The
Action Plan outlines goals, tasks, and time frames
to be accomplished across six topical areas
(domains): Outdoor Spaces and Buildings, Social
and Civic Participation, Community Information,
Housing, Transportation, and Community Health
and Wellness. Of these, the Outdoor Spaces and
Buildings domain contains the following goal and
action items that relate to trees.

GOAL
Goal 1.3 Improve accessibility and comfort of
all public facilities throughout the City

OBJECTIVES AND SPECIFIC ACTION
STEPS

2. Include sidewalks as a part of what is
defined as “public space” in La Mesa.
a. Complete the Sidewalk Master Plan in full.
b. Create more all-weather walking surfaces
for accessibility.
c. Create wider sidewalks to include more
pedestrian amenities and shade trees.
d. Consider sidewalk decorations to
emphasize the sidewalk as a safe, public
space for all ages to use.

As indicated in the plan, inclusion of trees in
sidewalks is intended to be implemented on a
per-project basis for all sidewalk improvement
projects, which would be overseen by the
City’s Transportation Department. Another
way that the Action Plan includes trees is
by identifying specific goals and objectives
related to trees from other City plans that the
Action Plan would support. These include the
aforementioned goals and objectives from
the Downtown Villages Specific Plan and the
Bicycle Facilities and Alternative Transportation
Plan.

RELATIONSHIP TO THE UFMP
As sidewalk improvement projects are
implemented per the Action Plan, the UFMP
can be used as a reference document for
tree planting standards and species selection
for trees that will provide the greatest shade
benefits, creating a more comfortable
pedestrian environment. Additionally,
Appendix F provides tree and sidewalk
conflict resolution or avoidance strategies
that can be implemented during installation
of new sidewalks or when repairing existing
sidewalks to reduce the likelihood for trip and
fall hazards and ensure that pedestrian routes
remain passable for residents of all ages.

5.4 Planning Setting
Recommendations

1. Evaluate canopy cover goals established
in the CAP to determine whether goals are
achievable. Reexamine the methodology
used to calculate potential canopy cover in
the City and consider aligning the CAP with
the UFMP canopy analysis and goals.

2. Keep track of tree plantings to track
progress toward the GHG reduction
strategies outlined in the CAP. Use urban
forestry tools for calculating environmental
services provided by tree plantings, such as
iTree Eco.

3. Plant trees along multimodal
transportation networks (i.e., bike and
pedestrian routes) to encourage active
transportation. Trees can increase safety
for pedestrians and bicyclists by calming
traffic and providing a buffer from vehicles,
as well as make active transportation routes
more comfortable and enjoyable. Explore
alternative solutions for sidewalk design
(see Appendix F) to reduce/avoid tree and
sidewalk conflicts, minimize trip and fall
hazards, and ensure routes remain safely
passable.

4. Include trees in City park improvement
projects or development projects. Prioritize
planting large shade trees and species
that provide habitat to maximize the
environmental services provided by City
trees.

5. Adopt an ordinance/policy that outlines
tree planting requirements and mitigation
strategies related to tree removal and
tree replacement in development and
redevelopment projects. Options to consider
include, but are not limited to, establishing a
tree replacement mitigation ratio, minimum
shade requirements for specific projects/
land use types, and an in-lieu fee program to
provide a revenue stream for the City’s tree
program.

6. Establish metrics for tracking tree
plantings throughout the City to track
progress toward long-range planning goals.

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6. Community
Engagement
To ensure a successful, realistic, and
implementable UFMP, and to understand
the diverse opinions of residents, business
owners, and City leadership regarding trees,
several community engagement efforts were
conducted

6.1 Working Group
The City’s UFMP Working Group was formed
to bring together City staff and community
members to help advise the UFMP’s
development. The working group consisted of
two City staff from departments that manage or
influence trees; representatives from the City’s
Youth Advisory, Community Services, Traffic, and
Environmental Sustainability Commissions; and
an independent arborist and landscape architect
(Table 33). A total of six working group meetings
were held between May 2020 and November
2020, each in an open forum format facilitated by
the consultant team and City staff.

During the Working Group meetings, members
created the UFMP vision statement, completed
the Vibrant Cities Lab Gap Score Analysis,
developed and distributed an online public
survey, and played an integral role in developing
the guiding principles, goals, and strategies that
have been discussed throughout the UFMP. The
working group members who are City residents
provided context for citizens’ priorities, values,
and focus for the UFMP, while City staff dedicated
time through departmental interviews and
meetings to provide valuable insights into the
inner workings of the City, identify opportunities
and challenges, and share current information on
the management and maintenance practices of
the City-managed trees.

In addition to forming the framework for the
UFMP, the Working Group identified areas where
public education about tree management and
health will increase the success of the goals
identified in the UFMP. One area included the
need to help the public understand their role in
helping the City reach its City tree canopy cover
goal. La Mesa currently has a 12.4% canopy
cover with 88% of those trees existing on private
property single-family home lots, business
centers, and commercial properties (see Section

2.3). Therefore, residents and business owners
can make important contributions to Citywide canopy cover by planting new trees and properly maintaining the trees they manage.

The Working Group reported they frequently
observe management practices of privately
managed trees that do not support tree vigor
and growth, including poor establishment care
and inconsistent pruning like tree topping. As

6. Community Engagement

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such, effort was put towards considering new
ways to educate residents and businesses about
proper tree care.

6.2 Tree San Diego and
Urban Corps Partnership
Tree San Diego is a nonprofit organization
dedicated to increasing the quality and density
of the urban forests of San Diego and the
surrounding communities. La Mesa identified
Tree San Diego to lead tree planting efforts
of 350 trees as a part of the requirements of
the California Department of Forestry and
Fire Protection grant that is funding the UFMP
project. In collaboration with UrbanCorps, an
environmental job training program for young
adults, an additional 100 trees will be planted
in the City. The City prioritized the tree planting
effort to begin in disadvantaged communities as
defined by CalEnviroscreen 3.0. Tree inventory
data was used to further refine areas in the
target communities that were lacking trees and
locations where the new trees could be planted.

Several events and efforts were planned to
engage community members with the tree
planting process. Tree San Diego assisted with
creating and distributing mailers to 700 homes,
Table 33. La Mesa’s Urban Forest Management Plan Working Group Membership Name Affiliation Sector
Robin Rivet
Environmental Sustainability
Commission (former)
Community member, Consulting
Horticulturist/Landscape Designer, ISA
Certified Arborist
Tony Ortega
Traffic Commission Landscape architect
Chris Langdon
Design Review Board Landscape architect
Maya Sellers
Youth Advisory Commission Youth community member
Peter Spiller
Community Services Commission Community member
Cesar Romero
City of La Mesa Local government
Lyn Dedmon
City of La Mesa Local government
Hilary Ego
City of La Mesa Local government
Andrea Beth Damsky
Environmental Sustainability
Commission
Community member
the majority of which are adjacent to the sites
where the new trees will be planted. The goal
of the mailers was to inform residents of the
opportunity to receive a free street tree planted
by the City if the resident agreed to water and
care for the trees once they’ve been planted.

As of June 15, 2021, 122 residents agreed to
adopt trees. On February 27, 2021, Tree San
Diego hosted a free tree steward training via
Zoom, which focused on topics such as right
tree-right place, establishment care, and tree
health. Those who attended the training became
certified as Tree Stewards. Tree San Diego and
the City originally planned to hold a community
tree planting event in fall 2021 to further
engage residents in the tree planting process
and to attract attention to the planting efforts.

Unfortunately, due to COVID-19 restrictions, the
public was not able to participate in this event,
but a project kick-off tree planting was completed
by UrbanCorps that abided by the current
Centers for Disease Control guidelines for group
gatherings and social distancing. Finally, Tree
San Diego maintained several email lists of La
Mesa residents who identified an interest in
environmental projects and/or getting involved in
local City initiatives to keep them informed about
tree planting plans.

6.3 Online Content and
Social Media
The City uses Facebook, Instagram, Twitter, and
YouTube accounts to interact with community
members on a regular basis. The City has used
these platforms to coordinate posts to highlight
the benefits of trees and to advertise upcoming
tree planting efforts. A video is currently being
developed that will capture the UFMP planning
process, community outreach efforts, and the
importance of UFMP implementation. This video
will be showcased on the City’s website as well as
its social media platforms.

The City continues to work with Tree San Diego
to develop social media and website content
to educate residents about the environmental
benefits of planting trees and future tree planting
events.

The City has a “Tree Interest Form” on the City’s
website where residents can fill out a form to
express interest in receiving a future tree or stay
up to date on the City’s urban forest efforts.

Tree planting in La Mesa

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accordance with industry standards, and to
maintain canopy cover within parking lots that
meets the City’s sustainability goals.

As previously mentioned, a core issue to
preserving and growing the City’s canopy cover
will depend on the willingness of single-family
homeowners to protect and plant trees on
their property. The main threats to privately
managed trees identified by respondents
included drought, conflicts with other City
infrastructure, and/or a property owner not
wanting a tree in a certain area anymore.

Despite these threats, 89% of respondents
agreed or strongly agreed that homeowners
should be encouraged to plant more trees
on their property, with 43% ready to plant a
new tree on their property, and 28% willing to
volunteer at a tree planting event.

These metrics demonstrate that City residents
might be more in favor of efforts that give
single-family homeowners the option to
plant trees on their property, like a free tree
giveaway program. Programs would also
require an extensive education and outreach
component so that residents understand the
value of trees, become active participants
in planting new trees correctly, and protect
mature trees. The tree steward trainings
offered by Tree San Diego could be one piece
of the education program, and respondents
identified social media and materials mailed
to residents as the most effective ways to
educate the community on the value of trees
to the City.

6.5 Community Feedback
on the UFMP
The City posted the draft UFMP on its
website for public review and comment from
September 1, 2021 to September 30, 2021.

Six responses were received from community

6.4 Online Survey

6.4.1 Background and Methods
An online survey was created to identify the
public’s perception and understanding of the
City’s trees, and to offer a space for public
feedback as the City develops its UFMP. The
survey results are intended to establish a
framework for future public education about
the urban forest and trees and provide data to
support program development for outreach
activities. The survey consisted of 26 questions,
aimed to learn more about the following:
• The attitudes and feelings respondents
have towards trees
• How much respondents know about trees
and how to maintain them
• How willing respondents would be to
support policies that protect trees on
private property
• How willing respondents would be to
support programs that grow trees in the
public space
• Demographics of survey respondents
The survey was distributed through various City
social media outlets, local newspapers, outreach
events, and communications by the working
group members.

6.4.2 Results
A full list of survey questions and responses can
be found in Appendix G. In total, 116 survey
responses were recorded. Of the respondents,
93% live in La Mesa, with representation from
each of the seven zones in the City (Table 34).

Table 35 highlights the other relevant survey
respondent demographics, and how they
compare with City demographics. The survey
respondents are skewed towards older, singlefamily homeowners, with higher education levels than the majority of the City’s residents.

For example, approximately 81% of survey
respondents identified as homeowners, which
is a high percentage compared to La Mesa’s
owner- versus renter-occupied housing statistics:
approximately 41% of La Mesa residents are
homeowners and renter occupied units make
up over half (59%) of La Mesa’s housing stock
(City of La Mesa 2021c). As such, it is important
to recognize the limitations of the survey results,
and to highlight that the opinions of non-white
residents, renters, residents under 50, and
commercial property and/or local business
owners are less likely to be represented.

The survey respondents highly value trees
in the City: 94% consider street trees to be a
valuable community asset that contributes
to their quality of life, and 90% rated trees as
either equal or more important than other
City infrastructure. Respondents rated the
most important benefits that trees provide as
improving environmental quality and cooling
homes or neighborhoods, and 78% think La
Mesa streets need more trees.

Most respondents (74%) agreed that tree
ordinances should be equitably enforced
to ensure that trees are properly managed
and maintained on both public and private
spaces. Respondents were also in favor of an
ordinance that required commercial properties
to properly prune and maintain trees in
Table 35. Demographics of Survey Respondents Compared to Demographics of the City of La Mesa Category
Survey Respondent
Demographics
La Mesa
Demographics*
Age
68% 50 or Older 25% 54 or Older
Housing Type
83% Single-Family Home 43% Single-Family Home
Housing Status
81% Homeowner 41% Homeowner
Race
75% White 71.4% White
Level of Education
75% Bachelor’s Degree or higher 36% Bachelor’s Degree or higher
Note: *Information based on City data from the U.S. Census Bureau.

Table 34. Responses to the La Mesa Zone Survey
Zone No. Respondents
Zone 1 25
Zone 2 16
Zone 3 7
Zone 4 15
Zone 5 13
Zone 6 11
Zone 7 12
Did not respond 17

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Table 36. Community Feedback on the UFMP
Theme Comment
Climate
Trees conflict with The City’s plans for increased building density and solar development.

Energy and water use for establishing new trees is extensive.

The City has ambitious goals for the urban forest related to combating climate change.

Existing Trees
Efforts should focus on preserving existing trees rather than planting new trees.

Plans for new development should preserve existing trees.

Adopt a Tree
Program
The residents’ role in the “adopt a tree” program for right-of-way trees should be limited to basic tree care activities (e.g., watering) and the City should be responsible for tree maintenance and liability. Residents will be disincentivized to adopt trees if they are held liable for loss/damage caused by the tree.

Community
Engagement
Seek funding for tree giveaway programs.

Provide residents with small trees to plant on property and guidance on tree care and maintenance.

Coordinate with local utilities to develop a private tree planting program, so any utility-generated incentives (e.g., turf removal) can be paired with tree planting.

Tree Ordinance Lack of support for a tree ordinance that requires permits for tree removals and penalizes private property owners for tree removals, especially in cases where tree is removed due to infrastructure conflicts (e.g., sidewalks, underground utilities, solar energy).

Tree Species
Plant trees that are adapted to San Diego’s Mediterranean climate.

Concerns regarding what will happen to existing palm trees as new development is planned.

Endemic palm trees should be on the recommended species list based on their low water requirements, and their shade, windbreak and habitat values.

Tree Planting Areas of the city with high CalEnviroSCreen scores should be priority planting areas. members that provided feedback on the draft
UFMP. A summary of responses received is
included in Table 36.

The community members who submitted
comments highly value trees, with four of the
six respondents indicating they support the
UFMP and the City’s goals to increase tree
planting in La Mesa, targeting areas of low
canopy cover. Two respondents expressed
concerns regarding the lack of palm tree
species on the recommended species list and
what would happen to the existing palm trees
in the City. While palm trees are iconic species
in southern California, as discussed in Section

2.5.5, palm species do not provide the same
level of environmental services and benefits
as other species. Although palm species are
not included on the recommended species list,
palm trees in the City would not be removed
solely based on this. Rather, trees in good
health would remain in place. However, when
trees need replacement due to reasons such
as declining health or age, they should be
replaced with species from the recommended
species list, which are species that are adapted
to La Mesa’s climate. This will maximize
environmental services that the City receives
from its urban forest.

6.6 Community Engagement
Recommendations

1. Increase outreach efforts to obtain input
from demographics that represent the
City of La Mesa. The demographic spread of
the survey respondents do not reflect those
of La Mesa, and there were a relatively low
number of responses compared to the City’s
population. To fully understand the City’s
challenges and opportunities to implementing
the UFMP, and to obtain survey results that
have statistical relevance, additional outreach
should be conducted to reach more residents
who are under 50, non-white, property renters
(both residential and commercial), and those
with mixed levels of education.

2. Develop a social media and branding
strategy that will help propel the UFMP
forward. Respondents to the survey identified
social media as the best way to educate City
residents. By using La Mesa’s existing social
media platforms, creating a consistent UFMP
social media plan and branding strategy
will help increase UFMP brand recognition
and inform community members of UFMP
progress.

3. Identify incentives that will encourage
citizens to plant, maintain, and protect
trees on their property or the City’s rightsof-way. Respondents to the survey indicate that they are ready to get involved with the
City’s tree planting efforts. New trees are
more likely to survive when they are adopted
by community members who are committed
to supporting the tree’s watering strategy
and establishment care (Mincey and Vogt
2014). In addition to distributing free trees for
City residents, La Mesa could consider other
programs that incentivize residents to plant
trees on their property such as tax credits,
free educational workshops, or free tree
maintenance provided by the City.

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7. Implementation
Plan &
Monitoring
Plan

7.1 Implementation Plan

7. Implementation Plan & Monitoring Plan
Immediate Actions (1-3 Years)
Strategic Plan
Objective Action

1.1a

1.1b
Adopt a new tree species palette and an integrated approach to urban forest planning that considers climate change and water resources.

1.1g

2.1e
Create nursery stock standards and partner with local tree nurseries to ensure tree species and quantities are available to meet tree planting goals.

1.2b

6.1d
Develop tree planting guidelines to maximize environmental services and benefits and ensure trees are planted according to the right tree, right place concept.

1.2c, 2.2b, 2.2d,

2.2e, 3.1a, 3.1b,

3.1c, 3.1d, 3.1e,

6.1d, 6.2b, 6.2c
Prioritize tree plantings based on low canopy cover, CalEnviroScreen scores, public health, walking/alternative transportation routes, excess hardscape, urban heat islands, stormwater management, and land use (e.g., residential, parks, schools, community gathering spaces, transportation and commercial corridors).

The following table prioritizes the Strategic
Plan objectives from Section 1.3. The left
column corresponds to the Strategic Plan
objectives outlined in the tables in Section 1.3,
and prioritizes them in terms of immediate,
mid term, and long term actions that the City
can take achieve the Strategic Plan objectives
and to progress toward a more sustainable
urban forest. As with any city initiative,
additional funding is required to take steps
toward achieving the objectives of this UFMP.

Appendix H includes funding sources that
they City may consider to increase funding for
the urban forest program.

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Immediate Actions (1-3 Years)
Strategic Plan
Objective Action

1.2a

2.1b

2.1c

2.1d

2.2e

2.2f
Develop an annual tree planting plan to reach canopy cover goals and full stocking of all available tree planting locations. Track tree plantings annually and adjust the annual tree planting goal every 5 years.

2.2a

4.1a

4.1c

4.1e

6.1a

6.1b

6.3d
Adopt ordinances for tree protection/replacement and landscaping requirements.

2.2c

4.1b

7.1a

7.1b

7.1c

7.1d

7.1e
Create a community outreach and education program and host community engagement events. Provide incentives for private property owners to plant trees.

Immediate Actions (1-3 Years)
Strategic Plan
Objective Action

4.2a

4.2b

4.2c

5.1h
Provide private property owners with tree maintenance information and options for the City to maintain private property trees to ensure trees are properly managed.

5.1b

5.1c

5.1e
Adopt tree establishment care guidelines and watering guidelines.

5.1g

5.1i

6.1e

6.1c
Update the City’s Tree Policy Manual, tree planting standard details, landscape standards and the plan review process.

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Mid Term Actions (3-10 Years)
Strategic Plan
Objective Action

1.1f

4.1d

5.1d

5.1f
Update the tree inventory in 3 to 4 years and establish a monitoring schedule to evaluate trees.

5.1a Include an arborist in urban forest planning efforts.

6.2a

6.2e
Improve active transportation networks and sidewalks by implementing tree plantings that increase safety and walkability. Ensure trees are selected and planted according to the right tree, right place concept to reduce conflicts with existing and proposed hardscape/sidewalks.

7.2a

7.2b

7.2c

7.2d
Increase funding for the urban forest program.

6.2d Design a pilot program that includes tree planting and improvements along one City block to be used as an example going forward.

6.3a

6.3b

6.3c

6.3e

6.3f
Update/revise City planning documents to reflect the goals, strategies and recommendations of the UFMP and ensure trees are considered as new plans are developed.

Long Term Actions (10+ Years)
Strategic Plan
Objective Action

1.1c

1.1d

1.1e
Maintain a diverse City tree inventory.

2.1a

2.1f
Achieve a 20% tree canopy cover by 2051.

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7.2 Monitoring Plan
One model the City can use to monitor the
implementation of the UFMP is the Vibrant Cities
Lab Community Assessment and Goal-Setting
Tool (Vibrant Cities Lab n.d.). The tool is used as
an assessment to define the City’s current state
of a specific area of urban forest sustainability.

The user decides what the City’s current state
of the metric is, and then sets where the goal
metric should be. Each metric is assigned a point
value, and the City is assigned a “Total Current
Score” and a “Gap Score,” or how far off the
current state is from the desired goal. A city that
has a gap score between 20 to 40 is not far from
achieving the goals of its urban forest program.

A gap score of 40+ indicates that a City is still
implementing programs and policies to develop
a sustainable urban forest, and will take longer in
achieving its ideal urban forest program.

La Mesa’s assessment was conducted on July
21, 2020, by working group members, City staff,
and the consultant team. Table 35 reflects
the results from the first assessment, which
set the baseline for the City’s “Total Current
Score” at its pre-UFMP metrics. Based on the
first assessment, the City has a current rating
of 11 and a gap score of 90. The City’s UFMP
monitoring plan should be based around the
Vibrant Cities Lab Community Assessment and
Goal Setting Tool and be retaken each year to
track, measure, and highlight progress. The
assessment can also be used to demonstrate
successes and justify additional funding tasks
to City Council. Since the City first took the
assessment, several of the responses that had
significant gaps, such as the lack of a UFMP
(5) and a City inventory (5), have already been
achieved.

Table 35. City of La Mesa’s Vibrant City’s Lab Urban Forest Assessment Results.

Category Current Rating Goal Rating Gap
Canopy cover The existing canopy cover for entire
municipality is <50% of the desired canopy.
-1 The existing canopy is >75%-100% of
desired – at individual neighborhood
level as well as overall municipality.
4 5
Inventory and assessment
methodology
Complete or sample-based inventory of
publicly owned trees.
1 Systematic comprehensive inventory
system of entire urban forest – with
information tailored to users and
supported by mapping in municipalitywide GIS [geographic information system]. Provides for change analysis.
4 3
Complete, detailed, and spatially explicit,
high-resolution Urban Tree Canopy (UTC)
assessment based on enhanced data (such
as LIDAR) – accompanied by comprehensive
set of goals by land use and other
parameters.
3 As described for "Better" rating – and
all utilized effectively to drive urban
forest and green infrastructure policy
and practice municipality-wide and at
neighborhood or smaller management
level.
4 1
Publicly owned trees Complete tree inventory that includes detailed tree condition ratings
2 Complete GIS tree inventory that
includes detailed tree condition and risk
ratings.
4 2
Publicly owned natural areas No information -1 Management plan focused on sustaining and, where possible, improving overall
ecological structure and function while
facilitating appropriate public use. Plan
should consider impacts on contiguous
natural areas [open space corridors]
outside the community’s borders.
4 5
Private property trees Aerial, point-based assessment—capturing extent and location
1 Bottom-up sample-based assessment,
as well as detailed urban tree canopy
analysis of entire urban forest, including
private property, integrated into
municipality-wide [multi-agency] GIS
system. LIDAR and hyper-spectral
imaging most helpful.
4 3
Tree planting and maintenance, La Mesa, CA

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Table 35. City of La Mesa’s Vibrant City’s Lab Urban Forest Assessment Results, continued.

Category Current Rating Goal Rating Gap
Relative performance index by species Half of the six most common species have higher RPI scores than the average of all
species in community
2 All six most common species have higher
RPI scores than the average of all species
in community. (>1.)
4 2
Use of native vegetation No coordinated focus on native vegetation -1 Use of native species is encouraged on a project-appropriate basis in all areas;
invasive species are recognized and
discouraged on public and private lands.
2 3
Align municipal departments Municipal departments/agencies take actions impacting urban forest with no
cross-departmental coordination or
consideration of the urban forest resource.
-1 Informal teams among departments and
agencies communicate regularly and
collaborate on a project-specific basis.
2 3
Engage residents in planning and
implementation
Many active neighborhood groups
engaged in advancing urban forest goals,
but with little or no overall coordination
with municipality or its partnering NGOs
[nongovernmental organizations].
2 Proactive outreach and coordination
efforts by municipality and
nongovernmental organization
partners resulting in widespread citizen
involvement and structured engagement
among diverse neighborhood groups.
4 2
Environmental equity Tree planting and outreach is not
determined equitably by canopy cover or
need for benefits.
-1 Equitable planting and outreach at
the neighborhood level is guided by
strong resident involvement in low
canopy/high need areas. Residents
participate actively in identifying needs
for their neighborhoods, planning,
implementation, and monitoring.
4 5
Trees acknowledged as vital
community resource
Trees generally recognized as important
and beneficial.
1 Urban forest recognized as vital to the
community’s environmental, social, and
economic well-being.
4 3
Table 35. City of La Mesa’s Vibrant City’s Lab Urban Forest Assessment Results, continued.

Category Current Rating Goal Rating Gap
Engage large private landowners and
institutions
Large private landholders are generally
uninformed about urban forest issues and
opportunities.
-1 Landowners develop tree management
plans that advance municipal urban
forest goals.
2 3
All utilities work with municipality,
employ best management practices
Utilities take actions impacting urban forest
with no municipal coordination.
1 Utilities are included in informal municipal teams that communicate regularly and collaborate on a project-specific
basis.
3 2
Green industry embraces goals, high
standards
Little or no cooperation among segments of
green industry or awareness of municipality-wide urban forest goals and objectives. -1 Shared vision and goals and extensive
committed partnerships in place. Solid
adherence to high professional standards and commitment to credentialing and continuing education.
4 5
Develop urban forest management
plan
No urban forest management plan -1 New or recent urban forest and green infrastructure management plan which
targets public and private tree planting
and protection based on assessment of
anticipated benefits, and ensures these
benefits are distributed equitably among
neighborhoods.
4 5
Cooperative planning with other
municipalities
Some neighboring municipalities and
regional agencies share similar urban forest
policies and plans.
1 Widespread regional cooperation resulting in development of regional urban forestry strategy.
4 3
Forestry plan integrated into other
municipal plans
Urban forestry plan mentions how it could
meet other municipal objectives or inform
other planning efforts.
-1 All agencies whose goals are served by
urban forestry practices, participate in
creation of forestry plan, and commit to
designated roles and responsibilities.
4 5

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Table 35. City of La Mesa’s Vibrant City’s Lab Urban Forest Assessment Results, continued.

Category Current Rating Goal Rating Gap
Urban forestry program capacity Lack of personnel and/or adequate equipment severely limits needed
maintenance. Few resources, if any available
to achieve new goals.
-1 Team has capacity in terms of trained
staff and equipment to achieve
many of the goals of the urban forest
management plan.
2 3
Municipality-wide urban forestry
funding
Ad hoc funding for emergency, reactive
management.
1 Sustained, long-term funding from
multiple municipal, regional and/or state
agencies, along with private sources
to implement a comprehensive urban
forest management plan and provide for
maintenance and adaptive management
as circumstances change.
4 3
Growing site suitability Appropriate tree species are considered in site selection
1 All trees planted in sites with adequate
soil quality and quantity, and with
sufficient growing space and overall
site conditions to achieve their genetic
potential and thus provide maximum
ecosystem services. Where growing
conditions are poor, guidance provided
on how to improve soil volume, quality,
and other factors.
4 3
Management of publicly owned
natural areas
Only reactive management to facilitate
public use, e.g., hazard abatement, trail
maintenance.
1 Management plan for each publicly
owned natural area focused on
sustaining and, where possible,
improving overall ecological integrity
(i.e., structure and function) – while
facilitating appropriate public use.
4 3
Table 35. City of La Mesa’s Vibrant City’s Lab Urban Forest Assessment Results, continued.

Category Current Rating Goal Rating Gap
Policies that foster good urban forestry on private landsNo tree protection ordinance, or one that's weak and rarely enforced.
-1 All relevant municipal policies require or
incentivize adherence by private owners to
standards incorporated in the plan. Incentives and sanctions applied when appropriate. 4 5
Tree protection policy and enforcementPolicies in place to protect public trees and employ industry best management practices, but rare or inconsistent enforcement. 1 Integrated municipality-wide policies and
practices to protect public and private trees,
consistently enforced and with penalties
sufficient to deter violations.
4 3
Monitoring Monitoring is infrequent and reactive to
reported changes in tree health, site condition.
1 Monitoring on a regular basis with rotating schedule for each area. Monitors are professionals or volunteers trained to collect
specific data required by municipality. Multiyear data available for trend analyses. 2 1
Tree risk management The community has written tree risk management policy (aka, 'standard of care')
and an operational plan for inspecting and
mitigating reported tree problems, including
a timetable for mitigating potential hazards.
2 Includes "better" but with TRAQ [Tree
Risk Assessment Qualification]-qualified
contractors on City projects. Educate
tree care companies and public about
importance of TRAQ qualifications.
4 2
Urban wood and green waste
utilization
The majority of green waste is reused
or recycled – for energy, products, and
other purposes beyond chips or mulch.
2 Comprehensive plan and processes in
place to utilize all green waste one way
or another, to the fullest extent possible.
4 2
Total Current Score 11 Total Goal Score 101 Gap
Score
90

148 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 149 5 Planning Setting
Glossary
Albedo – the measure of the fraction of solar energy reflected by the Earth's surface. Lighter color surfaces reflect light and have a high albedo, while darker surfaces absorb light and have a low albedo.

American National Standards Institute (ANSI) –The American National Standards Institute is a private non-profit organization that oversees the development of voluntary consensus standards for products, services, processes, systems, and personnel in the United States.

American National Standards Institute A300 Standards (ANSI A300)- ANSI A300 standards are the generally accepted industry standards for tree care practices. They are voluntary industry consensus standards developed by Tree Care Industry Association (TCIA) and written by a committee called the Accredited Standards Committee (ASC) A300, whose mission is to develop consensus performance standards based on current research and sound practice for writing specifications to manage trees, shrubs, and other woody plants.

Arborist – an individual who is trained in the art and science of plant- ing, caring for, and maintaining individual trees.

CalEnviroScreen 3.0 - aa science-based mapping tool that helps identify California communities that are most affected by many sources of pollution, and that are often especially vulnerable to pollution’s effects using environmental, health, and socioeconomic information to produce a numerical score for each census tract in California.

Canopy cover – - the area of land covered by a tree’s leaves and branches when viewed from above. Also referred to as urban forest canopy cover.

Choker effect – designed to slow vehicles at a mid-point along the street through narrowing the street width at a specific location.

Diameter at standard height (DSH) – a measurement, usually in inches, of a tree’s diameter taken at 4.5 feet above the ground. This measurement is also commonly referred to diameter at breast height (DBH).

Historic tree (landmark tree) – a tree in a landscape that has devel- oped historical, cultural, or aesthetic value because of its age, descent, legendary stature, representation of genus or species, rarity, or associ- ation with an important event or person.

Immature tree – any tree with a diameter at standard height (DSH) of 6” or less.

International Society of Arboriculture (ISA) – International Society of Arboriculture (ISA)- serves the tree care industry as a membership association and a credentialing organization that promotes the profes- sional practice of arboriculture. ISA focus areas include research, tech- nology, and education to advance best tree care practices. ISA delivers educational publications, services, events, and credentials that pro- vide opportunities for tree care professionals to develop their knowl- edge, skills, and arboricultural expertise. ISA also works to educate the public about the benefits of trees and the need for proper tree care. i-Tree Eco (application) – a computer-based program that uses tree measurements and other data to numerically estimate, both in eco- nomic and environmental terms, the quantity of ecosystem services Glossary

150 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 151 5 Planning Setting Glossary Glossary
and the associated value that a given set of trees provide to a given area.

Impervious surface – – typically a man-made structure such as roads, sidewalks, parking lots, and buildings that are covered with covered with a material that does not allow water to penetrate it, such as concrete, asphalt, metal, brick or stone. Highly compacted urban soils can also serve as impervious surfaces.

Landmark tree – see historic tree.

Mature tree – any tree with a diameter at standard height (DSH) of 24 inches or more.

Middle-aged tree – any tree with a diameter at standard height (DSH) between 19” and 24”.

Pruning – the selective removal of certain parts of a plant such as branches, buds, or roots. Pruning typically involves removing diseased, damaged, dead, non-productive, structurally unsound, or unwanted tissue from trees or other plants.

Pruning cycle – the time scheduled between pruning events. In a municipal setting, this cycle is typically between 5-7 years, and depends on the species of tree.

Relative performance index (RPI) – The percentage of a single species tree rated as being in good condition, divided by the percentage of all species of trees rated in good condition in a given area.

Right tree, right place – - an industry-accepted approach for making tree and landscaping selections to ensure that the vegetation planted is appropriate for a specific purpose or location.

Species diversity- the number of different tree species that are represented in a given area.

Tree canopy – - the extent of the outer layer of leaves of an individual tree or a group of trees.

Tree inventory – the gathering of accurate information on the health and diversity of trees of in a given area. Tree inventories can be a sample, partial, or complete analysis of the trees in a given area.

Tree protection ordinance – an ordinance or policy that protects trees from removal and/or damage. Also referred to as tree protection policy.

Tree protection policy – see tree protection ordinance
Tree staking – staking provides support to newly planted or damaged trees by connecting the trunk to a nearby steel or wooden post.

Urban forest – all the trees, both publicly managed by a city, and privately owned by residents and business owners, in an urban environment Urban forest canopy – see canopy cover.

Urban Forest Management Plan (UFMP) – a roadmap that creates a shared vision for the future of a tree canopy in a given area. The plan guides stakeholders to effectively manage and provide for maximum, long-term benefits of the urban forest to the community.

Urban heat island (UHI) – a metropolitan area that is significantly warmer than the areas surrounding it, due to human activities.

Vibrant Cities Lab ‘Community Assessment & Goal-Setting Tool’ - a tool used to measure where a given city’s urban forest program is in relation to ideal sustainable urban forest management practices.

Vision- The City of La Mesa will foster a sustainable urban forest that supports residents living in an equitable, healthy environment, resilient to climate change, which builds connections between neighbors, and showcases La Mesa’s identity as the “Jewel of the Hills”.

Working Group– a group of key city staff, elected officials, and community stakeholders who have a role or voice in the management of the urban forest. This group helps formulate the vision and goals for the urban forest management plan and provides valuable insights into current management practices.

Young tree – any tree with a diameter at standard height (DSH) of 7 inches to 18 inches.

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Appendices
Appendices

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Appendices
Appendix A Appendix A

APPENDIX A
Canopy Cover Methodology
Canopy Cover Analysis Methodology
The City’s existing canopy cover was determined by analyzing spatial data and satellite imagery to create an updated map of tree canopy and other land cover classes in La Mesa. The tree canopy analysis, referred to herein as the 2020 Land Cover Distribution Study, was derived using WorldView satellite imagery, current tree height data, and artificial intelligence (AI)/machine learning. Three critical data types were collected: (1) satellite imagery, (2) a digital surface model (DSM) indicating the elevation of all features within the area of interest, and (3) a digital terrain model that represents bare ground elevations within the area of interest. This data was used to classify land cover types throughout the City including: (1) tree, (2) grass/shrub, (3) bare ground (e.g., dirt) and impervious surfaces (e.g., buildings, roads, etc.), and (4) water.

Satellite imagery was obtained from WorldView 3 (WV-3) satellite data. A single multispectral WV-3 scene was collected on July 24, 2019, which had 0% cloud cover. Various sources were explored for the DSM data, including the 2014 LiDAR data. However, because the 2014 LiDAR data is older than the July 2019 WV-3 multispectral imagery, multiple differences were observed in the tree canopy size and status. Thus, the LiDAR data was not used to represent the current status of the tree canopy, and the DSM data was purchased from the company Nearmap. The bare ground elevations in the 2014 LiDAR data were still useful for this study and were used to represent ground elevations. The DSM data uses an aerial image-based photogrammetric process, where a high number of overlapping aerial images are collected from different positions in the sky, and the elevation values of individual features within the scene are calculated at a high level of detail. The Nearmap DSM data was projected to NAD83 (2011) State Plane California Zone VI US Feet, with a vertical datum of NAVD88 Geoid 12A (to match the 2014 imagery and LiDAR product collected by the SANDAG consortium). The heights of various features in the scene (e.g., trees, buildings) were determined by subtracting the digital terrain model elevation values from DSM elevation values to achieve a normalized DSM (or nDSM). The AI model was refined over time to recognize the various land cover types. Ultimately, the AI classification process utilized multispectral imagery and nDSM height values for the image-based land cover classification process. However, the AI model had difficulty separating bare earth from impervious surfaces, and those classes were categorized jointly. For comparison, canopy coverage LiDAR data that was previously collected in 2014 was reviewed, and canopy coverage was also assessed using iTree Canopy software.

164 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 165 5 Planning Setting Appendix B Appendix B

APPENDIX B
Tree Inventory by Maintenance Zone Maps
Date: 5/3/2021 - Last saved by: bdokkestul - Path: Z:\Projects\j1245501\MAPDOC\DOCUMENT\Figure3_1through8_MaintenanceZones_TreeINV_Mapbook.mxd §¨¦8

48.51% Vacant
SOURCE: SANGIS 2019, City of La Mesa 2021
0 700 1,400 n Feet
ÄÆ94
1 ÄÆ25
8 4
5 1 2
3 7
6 §¨¦8
City of La Mesa
Maintenance Zone
!H Available Tree Planting Locations
!H Inventoried Public Trees
Tree Inventory and Available Planting Locations in Maintenance Zone 1 City of La Mesa Urban Forest Management Plan

166 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 167 5 Planning Setting Appendix B Appendix B
Date: 5/3/2021 - Last saved by: bdokkestul - Path: Z:\Projects\j1245501\MAPDOC\DOCUMENT\Figure3_1through8_MaintenanceZones_TreeINV_Mapbook.mxd ÄÆ94

25.04% Vacant
SOURCE: SANGIS 2019, City of La Mesa 2021
0 600 1,200 n Feet
ÄÆ94
1 ÄÆ25
8 4
5 1 2
3 7
6 §¨¦8
City of La Mesa
Maintenance Zone
!H Available Tree Planting Locations
!H Inventoried Public Trees
Tree Inventory and Available Planting Locations in Maintenance Zone 6 City of La Mesa Urban Forest Management Plan
Date: 5/3/2021 - Last saved by: bdokkestul - Path: Z:\Projects\j1245501\MAPDOC\DOCUMENT\Figure3_1through8_MaintenanceZones_TreeINV_Mapbook.mxd 1 ÄÆ25
§¨¦8

37.88% Vacant
SOURCE: SANGIS 2019, City of La Mesa 2021
0 750 1,500 n Feet
ÄÆ94
1 ÄÆ25
8 4
5 1 2
3 7
6 §¨¦8
City of La Mesa
Maintenance Zone
!H Available Tree Planting Locations
!H Inventoried Public Trees
Tree Inventory and Available Planting Locations in Maintenance Zone 2 City of La Mesa Urban Forest Management Plan

168 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 169 5 Planning Setting Appendix B Appendix B
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16.9% Vacant
SOURCE: SANGIS 2019, City of La Mesa 2021
0 550 1,100 n Feet
ÄÆ94
1 ÄÆ25
8 4
5 1 2
3 7
6 §¨¦8
City of La Mesa
Maintenance Zone
!H Available Tree Planting Locations
!H Inventoried Public Trees
Tree Inventory and Available Planting Locations in Maintenance Zone 7 City of La Mesa Urban Forest Management Plan
Date: 5/3/2021 - Last saved by: bdokkestul - Path: Z:\Projects\j1245501\MAPDOC\DOCUMENT\Figure3_1through8_MaintenanceZones_TreeINV_Mapbook.mxd ÄÆ94
1 ÄÆ25
§¨¦8

21.46%
Vacant
SOURCE: SANGIS 2019, City of La Mesa 2021
0 850 1,700 n Feet
ÄÆ94
1 ÄÆ25
8 4
5 1 2
3 7
6 §¨¦8
City of La Mesa
Maintenance Zone
!H Available Tree Planting Locations
!H Inventoried Public Trees
Tree Inventory and Available Planting Locations in Maintenance Zone 4 City of La Mesa Urban Forest Management Plan

170 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 171 5 Planning Setting Appendix B Appendix B
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ÄÆ94

11.29% Vacant
SOURCE: SANGIS 2019, City of La Mesa 2021
0 600 1,200 n Feet
ÄÆ94
1 ÄÆ25
8 4
5 1 2
3 7
6 §¨¦8
City of La Mesa
Maintenance Zone
!H Available Tree Planting Locations
!H Inventoried Public Trees
Tree Inventory and Available Planting Locations in Maintenance Zone 5 City of La Mesa Urban Forest Management Plan
Date: 5/3/2021 - Last saved by: bdokkestul - Path: Z:\Projects\j1245501\MAPDOC\DOCUMENT\Figure3_1through8_MaintenanceZones_TreeINV_Mapbook.mxd1 ÄÆ25
§¨¦8

15.74% Vacant
SOURCE: SANGIS 2019, City of La Mesa 2021
0 750 1,500 n Feet
ÄÆ94
1 ÄÆ25
8 4
5 1 2
3 7
6 §¨¦8
City of La Mesa
Maintenance Zone
!H Available Tree Planting Locations
!H Inventoried Public Trees
Tree Inventory and Available Planting Locations in Maintenance Zone 3 City of La Mesa Urban Forest Management Plan

172 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 173 5 Planning Setting Appendix B Appendix B
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10.53% Vacant
SOURCE: SANGIS 2019, City of La Mesa 2021
0 135 270 n Feet
ÄÆ94
1 ÄÆ25
8 4
5 1 2
3 7
6 §¨¦8
City of La Mesa
Maintenance Zone
!H Available Tree Planting Locations
!H Inventoried Public Trees
Tree Inventory and Available Planting Locations in Maintenance Zone 8 City of La Mesa Urban Forest Management Plan

174 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 175 5 Planning Setting Appendix C Appendix C

APPENDIX C
CalEnviroScreen Results and Canopy Cover by Census Tract

CITY OF

LA MESA
La Mesa CalEnviroScreen Results and Canopy Cover by Census Tract 6073014804 City of La Mesa Urban Forest Management Plan
SOURCE: SANGIS 2019,City of La Mesa 2021
0 470 940Feet
94 125
8 12
1 2
11 3
10 6
4 7
13 5
9 City of La Mesa
Census Tract
Tree Canopy
Vegetation
Water
Building
Bare-earth, Impervious
Surfaces, Roads
FIGURE 4-1
CalEnviro Screen Results

3.0 Percentile Range
8 25-30%
30-35%
35-40%
45-50%
50-55%
65-70%
70-75%
55-60%
60-65%
, 11.02%

176 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 177 5 Planning Setting Appendix C Appendix C

CITY OF

LA MESA
125
8 8
La Mesa CalEnviroScreen Results and Canopy Cover by Census Tract 6073015100 City of La Mesa Urban Forest Management Plan
SOURCE: SANGIS 2019,City of La Mesa 2021
0 500 1,000Feet
94 125
8 12
1 2
11 3
10 6
4 7
13 5
9 City of La Mesa
Census Tract
Tree Canopy
Vegetation
Water
Building
Bare-earth, Impervious
Surfaces, Roads
FIGURE 4-3
CalEnviro Screen Results

3.0 Percentile Range

CITY OF

LA MESA
125
8 8
La Mesa CalEnviroScreen Results and Canopy Cover by Census Tract 6073015000 City of La Mesa Urban Forest Management Plan
SOURCE: SANGIS 2019,City of La Mesa 2021
0 600 1,200Feet
94 125
8 12
1 2
11 3
10 6
4 7
13 5
9 City of La Mesa
Census Tract
Tree Canopy
Vegetation
Water
Building
Bare-earth, Impervious
Surfaces, Roads
FIGURE 4-2
CalEnviro Screen Results

3.0 Percentile Range
8 8
25-30%
30-35%
35-40%
45-50%
50-55%
65-70%
70-75%
55-60%
60-65%
25-30%
30-35%
35-40%
45-50%
50-55%
65-70%
70-75%
55-60%
60-65%
, 9.88% , 11.61%

178 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 179 5 Planning Setting Appendix C Appendix C

CITY OF

LA MESA
8 8
La Mesa CalEnviroScreen Results and Canopy Cover by Census Tract 6073014803 City of La Mesa Urban Forest Management Plan
SOURCE: SANGIS 2019,City of La Mesa 2021
0 550 1,100Feet
94 125
8 12
1 2
11 3
10 6
4 7
13 5
9 City of La Mesa
Census Tract
Tree Canopy
Vegetation
Water
Building
Bare-earth, Impervious
Surfaces, Roads
FIGURE 4-5
CalEnviro Screen Results

3.0 Percentile Range

CITY OF

LA MESA
8 La Mesa CalEnviroScreen Results and Canopy Cover by Census Tract 6073014805 City of La Mesa Urban Forest Management Plan
SOURCE: SANGIS 2019,City of La Mesa 2021
0 550 1,100Feet
94 125
8 12
1 2
11 3
10 6
4 7
13 5
9 City of La Mesa
Census Tract
Tree Canopy
Vegetation
Water
Building
Bare-earth, Impervious
Surfaces, Roads
FIGURE 4-4
CalEnviro Screen Results

3.0 Percentile Range
8 8
25-30%
30-35%
35-40%
45-50%
50-55%
65-70%
70-75%
55-60%
60-65%
25-30%
30-35%
35-40%
45-50%
50-55%
65-70%
70-75%
55-60%
60-65%
, 12.68% , 9.55%

180 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 181 5 Planning Setting Appendix C Appendix C

CITY OF

LA MESA
125
125
8 8
La Mesa CalEnviroScreen Results and Canopy Cover by Census Tract 6073014902 City of La Mesa Urban Forest Management Plan
SOURCE: SANGIS 2019,City of La Mesa 2021
0 500 1,000Feet
94 125
8 12
1 2
11 3
10 6
4 7
13 5
9 City of La Mesa
Census Tract
Tree Canopy
Vegetation
Water
Building
Bare-earth, Impervious
Surfaces, Roads
FIGURE 4-7
CalEnviro Screen Results

3.0 Percentile Range

CITY OF

LA MESA
8 La Mesa CalEnviroScreen Results and Canopy Cover by Census Tract 6073014806 City of La Mesa Urban Forest Management Plan
SOURCE: SANGIS 2019,City of La Mesa 2021
0 600 1,200Feet
94 125
8 12
1 2
11 3
10 6
4 7
13 5
9 City of La Mesa
Census Tract
Tree Canopy
Vegetation
Water
Building
Bare-earth, Impervious
Surfaces, Roads
FIGURE 4-6
CalEnviro Screen Results

3.0 Percentile Range
8 8
25-30%
30-35%
35-40%
45-50%
50-55%
65-70%
70-75%
55-60%
60-65%
25-30%
30-35%
35-40%
45-50%
50-55%
65-70%
70-75%
55-60%
60-65%
, 11.5% , 9.79%

182 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 183 5 Planning Setting Appendix C Appendix C

CITY OF

LA MESA
La Mesa CalEnviroScreen Results and Canopy Cover by Census Tract 6073014700 City of La Mesa Urban Forest Management Plan
SOURCE: SANGIS 2019,City of La Mesa 2021
0 550 1,100Feet
94 125
8 12
1 2
11 3
10 6
4 7
13 5
9 City of La Mesa
Census Tract
Tree Canopy
Vegetation
Water
Building
Bare-earth, Impervious
Surfaces, Roads
FIGURE 4-9
CalEnviro Screen Results

3.0 Percentile Range

CITY OF

LA MESA
125
125
8 8
La Mesa CalEnviroScreen Results and Canopy Cover by Census Tract 6073015200 City of La Mesa Urban Forest Management Plan
SOURCE: SANGIS 2019,City of La Mesa 2021
0 750 1,500Feet
94 125
8 12
1 2
11 3
10 6
4 7
13 5
9 City of La Mesa
Census Tract
Tree Canopy
Vegetation
Water
Building
Bare-earth, Impervious
Surfaces, Roads
FIGURE 4-8
CalEnviro Screen Results

3.0 Percentile Range
8 8
25-30%
30-35%
35-40%
45-50%
50-55%
65-70%
70-75%
55-60%
60-65%
25-30%
30-35%
35-40%
45-50%
50-55%
65-70%
70-75%
55-60%
60-65%
, 20.22% , 12.59%

184 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 185 5 Planning Setting Appendix C Appendix C

CITY OF

LA MESA
94 La Mesa CalEnviroScreen Results and Canopy Cover by Census Tract 6073014500 City of La Mesa Urban Forest Management Plan
SOURCE: SANGIS 2019,City of La Mesa 2021
0 420 840Feet
94 125
8 12
1 2
11 3
10 6
4 7
13 5
9 City of La Mesa
Census Tract
Tree Canopy
Vegetation
Water
Building
Bare-earth, Impervious
Surfaces, Roads
FIGURE 4-11
CalEnviro Screen Results

3.0 Percentile Range

CITY OF

LA MESA
94 8
La Mesa CalEnviroScreen Results and Canopy Cover by Census Tract 6073014601 City of La Mesa Urban Forest Management Plan
SOURCE: SANGIS 2019,City of La Mesa 2021
0 550 1,100Feet
94 125
8 12
1 2
11 3
10 6
4 7
13 5
9 City of La Mesa
Census Tract
Tree Canopy
Vegetation
Water
Building
Bare-earth, Impervious
Surfaces, Roads
FIGURE 4-10
CalEnviro Screen Results

3.0 Percentile Range
8 8
25-30%
30-35%
35-40%
45-50%
50-55%
65-70%
70-75%
55-60%
60-65%
25-30%
30-35%
35-40%
45-50%
50-55%
65-70%
70-75%
55-60%
60-65%
, 9.66% , 12.47%

186 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 187 5 Planning Setting Appendix C Appendix C

CITY OF

LA MESA
94 125
La Mesa CalEnviroScreen Results and Canopy Cover by Census Tract 6073014901 City of La Mesa Urban Forest Management Plan
SOURCE: SANGIS 2019,City of La Mesa 2021
0 450 900Feet
94 125
8 12
1 2
11 3
10 6
4 7
13 5
9 City of La Mesa
Census Tract
Tree Canopy
Vegetation
Water
Building
Bare-earth, Impervious
Surfaces, Roads
FIGURE 4-13
CalEnviro Screen Results

3.0 Percentile Range

CITY OF

LA MESA
94 94
125
La Mesa CalEnviroScreen Results and Canopy Cover by Census Tract 6073014602 City of La Mesa Urban Forest Management Plan
SOURCE: SANGIS 2019,City of La Mesa 2021
0 625 1,250Feet
94 125
8 12
1 2
11 3
10 6
4 7
13 5
9 City of La Mesa
Census Tract
Tree Canopy
Vegetation
Water
Building
Bare-earth, Impervious
Surfaces, Roads
FIGURE 4-12
CalEnviro Screen Results

3.0 Percentile Range
8 8
25-30%
30-35%
35-40%
45-50%
50-55%
65-70%
70-75%
55-60%
60-65%
25-30%
30-35%
35-40%
45-50%
50-55%
65-70%
70-75%
55-60%
60-65%
, 12.06% , 19.35%

188 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 189 5 Planning Setting Appendix C Appendix C

CITY OF

LA MESA
94 94
125
La Mesa CalEnviroScreen Results and Canopy Cover by Census Tract 6073013801 City of La Mesa Urban Forest Management Plan
SOURCE: SANGIS 2019,City of La Mesa 2021
0 650 1,300Feet
94 125
8 12
1 2
11 3
10 6
4 7
13 5
9 City of La Mesa
Census Tract
Tree Canopy
Vegetation
Water
Building
Bare-earth, Impervious
Surfaces, Roads
FIGURE 4-14
CalEnviro Screen Results

3.0 Percentile Range
8 25-30%
30-35%
35-40%
45-50%
50-55%
65-70%
70-75%
55-60%
60-65%
, 18.59%

190 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 191 5 Planning Setting Appendix D Appendix D

APPENDIX D
Standards and Details
8

192 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 193 5 Planning Setting Appendix D Appendix D

194 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 195 5 Planning Setting Appendix D Appendix D
8

196 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 197 5 Planning Setting Appendix D Appendix D

198 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 199 5 Planning Setting Appendix D Appendix D
Tree Planting Standard Details
The City standard details for tree planting were adopted in 2008 and should be updated to reflect current arboriculture best practices for tree planting as defined by ISA, including detail LMSD LS-1, Tree Planting & Staking. Exhibits D-1 and D-2 provide drafts of recommended updated guidelines for tree planting and staking, with the corresponding update described in Table D-1. These updates could be adopted by the City or used to update the current City standards.

Table D-1. Additional Recommended Updates to Standard Detail LMSD LS-1, Tree Planting & Staking
LMSD LS-1, Tree Planting & Staking Details Recommended Update Approved Hose & Wire Ties Exhibit D-1 1
Top of Root Ball Min 1 inch Above Existing Soil Exhibit D-2 2 Approved Backfill Exhibit D-2 3
Lodge-Pole Pine Tree Stakes (To Be Installed at
the Discretion of the P.W. Superintendent). If
Required, Install Perpendicular to Prevailing Winds
Exhibit D-1 4
Maintain 6-inch Berm All Around Tree Well Exhibit D-2 5 Actual Root Ball Area Sloped for Drainage Exhibit D-2 6 Notes 2: Canopy Shall Not Extend Below 7 inches Exhibit D-2 7

200 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 201 5 Planning Setting Appendix D Appendix D
8 Exhibit D-1
1 1
1 4
Exhibit D-2

202 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 203 5 Planning Setting Appendix E

APPENDIX E
Tree Planting & Maintenance Agreement
Appendix E
E:\0700 Eng\DEVELOPMENT MANUAL\Forms (DO NOT COPY TO OTHER DIRECTORIES!)\Policy & Procedure\Street Tree Agreement.doc

TREE PLANTING & MAINTENANCE AGREEMENT

PUBLIC WORKS DEPARTMENT / ENGINEERING DIVISION
8130 Allison Avenue, La Mesa, CA 91941
Phone: 619.667.1166 • Fax: 619.667.1380

PLEASE READ THE FOLLOWING CAREFULLY BEFORE SIGNING THE AGREEMENT To join your neighborhood street tree planting in partnership with The City of La Mesa the responsibilities are:

Maintenance
In planting on the sidewalk or in the parkway adjacent to a property, the owner accepts responsibility for the tree's maintenance, both for the sake of its survival and for the beauty and safety of the neighborhood and all passersby.

Watering
Specifically, a tree must be watered deeply and regularly – initially, about 15-20 gallons once a week – as necessary to keep moist. The basin must also be weeded, kept full of soil, empty of trash and mulched as necessary.

The City of La Mesa staff will give you information and advice about watering and further maintenance at any time thereafter.

Maintenance responsibility can be voluntarily assumed by renters or even added to a lease; but ONLY THE PROPERTY OWNER can sign the TREE RECIPIENT AGREEMENT.

Pre-Planting Meeting
This is a brief (optional) gathering -usually less than a half hour long, which in same cases can be handled by phone, for working out last minute logistics, confirmation of plans for planting day.

I HAVE READ THE CITY OF LA MESA "TREE PLANTING & MAINTENANCE AGREEMENT" AND UNDERSTAND

THE RESPONSIBILITES I ASSUME IN JOINING A NEIGHBORHOOD PLANTING IN COOPERATION WITH THE CITY OF LA MESA.

We agree to accept responsibility for checking the water needs of each tree at our address each week for the first three years after planting, and watering accordingly. We also accept responsibility for keeping the tree wells free of leaves, debris and weeds and will maintain the stakes and ties until the time at which they should be removed.

I am the owner of the property for which I received the trees listed below (please print):

Property Owner's:
(Print Name) (Signature)
Address of Proposed Trees:

Cross Street:

Home Address:

Telephone: (H) (W) # of Trees:

Species:

Name and phone number of tenants or neighbors planning to plant or care for trees:

204 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 205 5 Planning Setting Appendix F Appendix F

APPENDIX F
Tree and Sidewalk Conflict Solutions

SIDEWALK SOLUTIONS
1 Tree and Sidewalk Conflict Solutions
Trees and sidewalks are both key pieces of urban infrastructure that contribute to the pedestrian environment. Both contribute to the character and sense of place in a community as well as provide health and economic benefits while offering a means for comfortable active transportation.

However, these two elements of the public streetscape are often in conflict with one another. Sidewalks and other hardscapes can preclude healthy tree growth and canopy development by limiting available soil volume, while tree roots often cause damage to sidewalks resulting in uplift and fall and trip hazards which can be costly to repair. These conflicts and the associated costs often overshadow the benefits provided by trees in the urban landscape, resulting in the removal of trees or the decision to avoid planting trees altogether. In reality, tree and infrastructure conflicts are due to inadequate site design and exacerbated by planting the wrong tree species for the allotted space. The cost of sidewalk repairs or removing and replacing trees is a significant investment that can be avoided with proper site design and species selection. There are a number of strategies for minimizing, avoiding or eliminating tree and sidewalk conflicts that can be employed by local or regional governments. Table 1 outlines tree and sidewalk conflict resolution tactics and design solutions that can be employed when replacing damaged sidewalks or installing new sidewalks. Employing these strategies is dependent upon policies, standards and design requirements, clear processes for implementation, and funding.

Local jurisdictions are required to abide by federal and state policies governing sidewalk design, such as the US Access Board Public Right-of-Way Accessibility Guidelines (PROWAG), Americans with Disabilities Act (ADA), and the California Building Code (CBC). Additionally, local jurisdictions can adopt local policies, standards, and plans that guide the management of trees and sidewalks. Examples include tree protection ordinances, street tree and sidewalk design requirements, tree planting standards and specifications, street tree lists, and long-range plans, such as urban forest management plans, bicycle and pedestrian plans/active transportation plans, the General Plan, and specific plans.

In order to successfully implement tree and sidewalk policies and standards, cities must have processes in place for implementation and maintenance, including review of development plans and strict code enforcement. If not managed within the same department, city departments managing street trees and sidewalks must maintain clear lines of communication and collaborate regularly. Approaching management of street trees and sidewalks within the same department can prove successful, as collaboration is easily facilitated. Forestry staff and engineers can jointly inspect conflicts or conduct plan review and work together to identify solutions. A formalized process will help guide these actions, such as outlined in the City of Seattle’s; many of the solutions provided in Table 1 are based on the Toolkit included in Trees and Sidewalks Operations.

Cities must have reliable funding for management and oversight of its tree and sidewalk programs in order to successfully resolve or avoid conflicts. This includes funding for staff, tree planting, plan review, inspection and code enforcement, and maintenance and repairs. Examples of possible revenue streams to fund forestry and sidewalk programs include allocations from the general fund, partnering with nonprofit organizations, or allocations from taxes or fees, such as a gas tax, utility tax or development impact fees. Additional funding may also come from less traditional approaches, such as establishing a City nursery or composting program and offering these products for sale.

206 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 207 5 Planning Setting Appendix F Appendix F

SIDEWALK SOLUTIONS
3 Pavers • Many types, materials,
and colors available
• More flexible than
concrete, providing room
for continued tree root
growth
• May be used as
temporary repair or
replacement, or when
installing new sidewalk at
the same time as trees
• Requires cutting to fit
around other
infrastructure (e.g.,
utilities, etc.)
• Not all available types
and materials are
suitable for all
locations, as required
depth of excavation
may vary
• Durability varies by type
$$–$$$
($10 to $50
per square
foot)
Decades
Image Source: Carroll’s Building Materials n.d.

Pervious
Concrete
• Allows air and water to
reach soil
• May encourage deeper
root growth and deter
shallow root growth,
reducing root damage to
sidewalks
• Provides better growing
conditions
• Requires deeper
excavation for
installation of subbase
layers
• Requires more
maintenance than
standard concrete
$$$–$$$$
($35 per
linear foot)
Decades
Image Source: Bay Area Pervious Concrete

SIDEWALK SOLUTIONS
2 Table 1. Tree and Sidewalk Conflict Solutions
Solution Type Pros Cons
Estimated
Cost
($–$$$$)
Useful Life
(YearsDecadesCenturies) Example Image
Materials
The following sidewalk solutions present various materials for replacement/repair of a damaged sidewalk that may be used instead of concrete.

Asphalt • Short-term to mediumterm solution
• Low initial cost
• More flexible than
concrete
• May be used as a
repair/replacement or for
new sidewalks
• Easily repaired
• Not widely used,
creating conflicts with
appearance and visual
character
• Useful life can vary
greatly
• Useful life shorter than
that concrete
$$
($22 per
linear foot)
Decades
Image Source: Seattle Department of
Transportation

208 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 209 5 Planning Setting Appendix F Appendix F

SIDEWALK SOLUTIONS
5 Alternative Sidewalk Design Construction Methods
The following sidewalk solutions present alternative sidewalk design and construction methods to better accommodate trees and resist damage to sidewalks.

Reinforced or
Thicker Slab
• Reinforcing concrete with
steel rebar or wire mesh
and/or using a thicker
slab helps resist uplift of
tree roots
• May be used to correct
uplift after other
corrective actions have
been taken
• May not be compatible
with future utility
installation
• Should not be used
where additional root
growth is anticipated
(i.e., sufficient soil
volume should be
provided)
$$–$$$
($60 per
linear foot
for
reinforced
slab and
$40 per
linear foot
for 4-inch
thickness)
Decades
Image Source: E. F. Gilman
Expansion Joints • Allow for some movement
of concrete
• Used to control the
location of cracking
• May be used as repair or
replacement or for new
sidewalks near existing
trees (where roots may
be pruned prior to
installation and
substantial root growth is
not anticipated)
• Should not be used
where significant
additional root growth is
anticipated (i.e.,
sufficient soil volume
should be provided)
• Short term solution
$
(varies)
Decades
Image Source: S. Kubiak and V. Kubiak

SIDEWALK SOLUTIONS
4 Porous Asphalt • Allows water to pass
through to soil
• May be used for
replacement of large
segments of sidewalk or
installation of new
sidewalks where
infiltration is desirable
(e.g., adjacent to
bioretention)
• Cannot be produced in
small quantities and
should only be used
when long sidewalk
segments are being
installed (e.g., multiple
blocks)
$–$$$
($30 per
linear foot)
Decades
Image Source: Porous Pave
Decomposed
Granite
• May be used as a
pathway or walkway
surface, or as a finished
surface on top of planting
soil in tree pits rather
than mulch
• Provides flexible but
walkable surface near
tree roots
• Best used in parks on
walking and cycling
paths, or similar settings
• May be used as a
temporary repair near
root zones or for
installation of new
pathways or walkways
• Not recommended for
busy pedestrian routes
(best in residential
areas)
• Requires more
maintenance than
asphalt or concrete, as
uneven settling can
occur
• Americans with
Disabilities Act
compliance may require
binders and regular
maintenance
$–$$
($12 per
linear foot)
Years
Image Source: Bike Orlando

210 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 211 5 Planning Setting Appendix F Appendix F

SIDEWALK SOLUTIONS
7 Bridging • Provides grade
separation between tree
root zone and sidewalk
• Does not require
compacted subgrade
allowing tree roots to
grow in soil
• Variety of materials can
be used such as concrete
or steel panels
• May be used as repair or
replacement of damaged
sidewalk or to preserve a
high value tree
• Site specific grading
requirements may
prevent use of this
technique
• A nonslip surface
treatment is required
for metal/steel
materials
• Additional Americans
with Disabilities Act
requirements related to
grade differentials
greater than 18 inches
$$$$
($225 per
linear foot)
Decades
Image Source: E. Gilman
Curb Extensions
(Bulb-Outs)
• Increases pedestrian
safety through traffic
calming and shortening
the crossing distance for
pedestrians
• Provides additional root
growth area reducing
likelihood of root damage
to sidewalks
• Provides flexibility for tree
species selection
• May be used in new
development or as
expansion of sidewalks
and planting space in
redevelopment
• Must consider impacts
to drainage and existing
utilities
• Must consider site
specific transportation
conditions or impacts,
including driver sight
lines as well as bicycle
and pedestrian facilities
$$$–$$$$
($50 per
linear foot
excluding
drainage
and ramps)
Century
Image Source: Dylan Passmore

SIDEWALK SOLUTIONS
6 Monolithic
Sidewalk
• The continuous
installation of concrete
with no grade change
between sidewalk and
street has greater weight
(mass) to resist tree root
uplift
• Reduces potential for
future weakness in
pavement infrastructure
• May be used in new
development and in
redevelopment
• Consideration must be
given to impacts related
to stormwater runoff
and drainage patterns
• Not ideal for areas
where new root growth
is expected (new
plantings or continued
growth)
$$$
($60 per
linear foot)
Century
Image Source: Seattle Department of Transportation
Tree
Pits/Expanded
Tree Pits
• Alternative to planting
strips where maintaining
sidewalk width is
important (e.g., business
districts)
• May be used in new
development where tree
pit sizing and tree
selection are coordinated
(“right tree, right place”)
or in existing
development where
sufficient space is
available to expand
existing tree pits
• Must establish
minimum sizing
requirements to ensure
adequate soil volume
• Continuous planter
strips are preferred
where feasible
$
($15 per
square yard
for widening
existing tree
pits.

No
additional
cost if
implemente
d in new
developmen
t design)
Decades
Image Source: Morristown Shade Commission

212 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 213 5 Planning Setting Appendix F Appendix F

SIDEWALK SOLUTIONS
9 Easement • May allow for use of
private property where
additional space is
needed
• Provides larger planting
area for new or existing
trees
• Requires coordination
with property owner
$–$$$
(Varies
based on
market
value or
dedication
from
property
owner)
Century
Image Source: Seattle Department of Transportation
Suspended
Pavement
Systems
• Provides space and soil
volume for new tree
plantings in areas that
could not have supported
tree root growth
• Prevents root damage to
pavement if implemented
at the correct time
• Involves removing and
repaving sidewalks if
they already exist in the
areas
• Site specific grading
requirements need to
be taken into
consideration
$$$–$$$$
(15-
$25/cubic
foot)
Decades
Image Source: DeepRoot

SIDEWALK SOLUTIONS
8 Curb
Realignment
• Shifts curb location to
widen the planting strip
• May be used for new
development or
redevelopment to provide
additional space for new
or existing trees
• Requires sufficient
street widths
• Must consider impacts
to other infrastructure
and utilities
• Must consider site
specific transportation
conditions or impacts
$$$–$$$$
($50 per
linear foot
excluding
drainage
modification
and ramps
Minimal
additional
cost if part
of new
developmen
t design)
Century
Image Source: Seattle Department of Transportation
Curving or Offset
Sidewalk
• Allows for walkways that
meander around planting
areas, allowing trees
more grow space
• Increases pedestrian
safety by separating
sidewalks from vehicular
traffic
• May be used in new
development or
redevelopment to
preserve existing trees or
to provide sufficient grow
space for new plantings
• Requires adequate
space in the right of
way
• May require easement
for use of private
property
$$–$$$
($38 per
linear foot)
Image Source: Bartlett Tree Care

214 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 215 5 Planning Setting Appendix F Appendix F

SIDEWALK SOLUTIONS
11 Foam Underlay • Provides a foam layer of
support between
pavement and tree roots
to help prevent damage
• Can offer an alternative
to root pruning when a
sidewalk needs to be
replaced but root pruning
would severely damage
the tree
• Best used to repair
damage caused by
mature tree roots
• Short term solution
• Not a good option for
tree species that have
rapid root growth
$–$$
($150 to
$250 per
location)
Years
Image Source: Costello and Jones
Modified Gravel
Layer
• Suppressed root growth
• More longevity than foam
underlay and serves the
same purpose
• Thickness of gravel
around roots can be
adjusted to
accommodate size
• Could wound tree roots
making the trees more
susceptible to soilborne
pathogens
• 4 inches of gravel is
needed, if excavation
would damage critical
existing roots
• Modified Gravel Layer
may not be an option
$
($0.70 per
square foot
at depth of 4
inches)
Decades
Image Source: E. Gilman

SIDEWALK SOLUTIONS
10 Lowered Tree
Sites
• Can help prevent soil
compaction due to
pedestrian traffic
• Can bring trees to streets
with limited planting
space and few
underground
infrastructure conflicts
• Can conflict with
underground
infrastructure; can only
be implemented in
areas that have limited
potential for conflict
• Lowered sites tend to
accumulate trash and
other debris, presenting
a maintenance issue
• Design must include a
drainage plan because
soil can be easily
oversaturated
$$$–$$$$ Decades
Image Source: Storm Tree
Root
The following sidewalk solutions present design solutions that specifically address tree roots.

Root Barriers • Deters root growth to
limit damage to
pavement
• May be added after tree
planting to retrofit or
address root issues
• Will not address all
issues from tree roots,
but will help deter
$
($8 per
linear foot)
Decades
Image Source: Green Tech

216 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 217 5 Planning Setting Appendix F Appendix F

SIDEWALK SOLUTIONS
13 Sources:

American Planning Association. 2009. Planning the Urban Forest: Ecology, Economy, and Community Development. Planning Advisory Service Report Number 555.

Bassuk et al. 2015; Bike Orlando 2020; Casey Trees 2008; Costello and Jones 2003; Elmendorf 2008; City of New York Parks & Recreation 2014; City of Seattle 2011; City of Seattle Department of Transportation 2014, 2015; City of Seattle Public Utilities 2015; Mann n.d.; Smiley 2008 Bassuk, N., Denig, B., Haffner, T. Grabosky, J., and Trowbridge, P. 2015. CU-Structural Soil ®: A Comprehensive Guide. Urban Horticulture Institute, Cornell University. http://www.hort.cornell.edu/uhi/outreach/pdfs/CU-Structural%20Soil%20-%20A%20Comprehensive%20Guide.pdf.

Bike Orlando. 2020. Ward Park, Winter Park, FL Biking, Hiking. E-Z Map, 35+ Photos. Accessed May 2021. https://www.bikeorlando.net/ward-park-winter-park.htm.

Casey Trees. 2008. Tree Space Design: Growing the Tree Out of The Box. Accessed May 2021. http://caseytrees.org/resources/publications/treespacedesign/.

Carroll’s Building Materials. n.d. “Classic Hexagon Pavers.” Accessed May 2021. https://carrollsbuildingmaterials.com/landscape-products/pavers-profiles-finishes/classichexagon-pavers/.

Costello, L. R. and K. S. Jones. 2003. Reducing Infrastructure Damage By Tree Roots: A Compendium of Strategies. Western Chapter of the International Society of Arboriculture.

City of New York Parks & Recreation. February 2014. Tree Planting Standards. Accessed May 2021. http://www.nycgovparks.org/pagefiles/53/Tree-Planting-Standards.pdf.

City of Seattle. 2011. Seattle Right-of-Way Improvements Manual. https://www.seattle.gov/rowmanual/manual/.

City of Seattle Department of Transportation. 2014. Street Tree Manual. Accessed May 2021. http://www.seattle.gov/documents/departments/sdot/about/documentlibrary /streettreemanualweb.pdf.

City of Seattle Department of Transportation. 2015. Tree Sidewalks Operations Plan. City of Seattle Public Utilities. 2015. Standard Specifications of Municipal Construction. Plans 100a, 421, 424, 425, 430.

Elmendorf, W. 2008. Planting and Aftercare of Community Trees. Penn State University Extension.

Green Tech. 2021. Ribbed Root Barrier Panels. https://www.green-tech.co.uk/hard-landscaping/tree-pit-root-barriers/ribbed-root-barrier-panels Mann, Gordon. N.d. Sidewalk and Root Conflicts: Mitigating the Conflict - An Overview. Accessed May 2021, on Municipal Research and Services Center (MRSC) website at:
http://mrsc.org/getmedia/4DD1A628-BD5A-49E3-B1EE-3D09525F63BE/m58mannmade.asp.

Martin, Justin. 2017. Trees and Sidewalks: A Strategic Approach to Conflicts. Green Infrastructure for Your Community. https://www.deeproot.com/blog/blog-entries/trees-andsidewalks-a-strategic-approach-to-conflicts Smiley, E. Thomas. 2008. “Comparison of Methods to Reduce Sidewalk Damage from Tree Roots,” inArboriculture & Urban Forestry 34(3):179-183.

SIDEWALK SOLUTIONS
12 Root Paths • Can proactively direct
paths for roots to grow,
when designed at the
beginning of planting
• Help direct roots around
utilities when planting
space is limited
• Drainage away from or
out of root path will
need to be considered
$–$$
($600 to
$800 per
tree)
Decades
Image Source: Seattle Department of Transportation
Steel Plates • Can be used as an
alternative to root
pruning
• Can be used to help
mitigate issues with roots
that have already
developed (reactionary)
• Can conflict with
underground utilities
• Requires sidewalk to be
removed and replaced
for installation
$$–$$$
($500 to
$1,000
per site)
Decades
Image Source: Gordan Mann

218 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 219 5 Planning Setting Appendix G Appendix G

APPENDIX G
Community Engagement Results
City of La Mesa Urban Forest Management Plan Survey

5.17% 6

31.03% 36

54.31% 63

9.48% 11
Q1 What rating would you give the condition of public space street trees in La Mesa? Public space street trees are defined as trees in the right-ofway, in parks, and other publicly owned land.

Answered: 116 Skipped: 0
TOTAL 116
Excellent;
quality is...

Good; quality
is sufficient
Fair; room to
improve
Poor; changes
needed
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

ANSWER CHOICES RESPONSES
Excellent; quality is optimal
Good; quality is sufficient
Fair; room to improve
Poor; changes needed

220 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 221 5 Planning Setting Appendix G Appendix G
City of La Mesa Urban Forest Management Plan Survey

0.00% 0

18.10% 21

77.59% 90

4.31% 5
Q3 What is your opinion regarding the number of trees along streets in the City of La Mesa?
Answered: 116 Skipped: 0
TOTAL 116
Too many trees
About the
right number...

Not enough
trees
Other (please
specify)
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

ANSWER CHOICES RESPONSES
Too many trees
About the right number of trees
Not enough trees
Other (please specify)
City of La Mesa Urban Forest Management Plan Survey

16.38% 19

74.14% 86

9.48% 11
Q2 Trees are considered part of the City’s infrastructure. How important do you think trees are compared to other infrastructure like streets, sidewalks, water, sewer, traffic signals, lighting, etc.?
Answered: 116 Skipped: 0
TOTAL 116
Trees are more
important th...

Trees are
equally as...

Trees are not
as important...
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

ANSWER CHOICES RESPONSES
Trees are more important than other infrastructure.

Trees are equally as important as other infrastructure.

Trees are not as important as other infrastructure.

222 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 223 5 Planning Setting Appendix G Appendix G
City of La Mesa Urban Forest Management Plan Survey

6.09% 7

3.48% 4

6.09% 7

27.83% 32

3.48% 4

53.04% 61
Q5 Select the option that represents the main issue you would have with a tree on your property.

Answered: 115 Skipped: 1
TOTAL 115
Maintenance
costs
Uses too much
water
They’re
messy/leaf...

Damage to
sewer...

Risk of
falling bran...

No issues
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

ANSWER CHOICES RESPONSES
Maintenance costs
Uses too much water
They’re messy/leaf litter
Damage to sewer pipes/sidewalks
Risk of falling branch damage
No issues
City of La Mesa Urban Forest Management Plan Survey

93.97% 109

4.31% 5

1.72% 2

0.00% 0
Q4 I consider my neighborhood street trees a valuable community asset that contributes to my quality of life in La Mesa.

Answered: 116 Skipped: 0
TOTAL 116
Definitely
Somewhat
Not at all
Not sure
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

ANSWER CHOICES RESPONSES
Definitely
Somewhat
Not at all
Not sure

224 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 225 5 Planning Setting Appendix G Appendix G
6 / 27
Most Important Second Most Important
g
Aesthetics or
appearance
Protecting
human health
Improving
property value
Traffic calming
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
City of La Mesa Urban Forest Management Plan Survey
Q6 Of the following options, select the top TWO most important benefits trees provide in your neighborhood.

Answered: 112 Skipped: 4
Improving the
environment...

Cooling
neighborhood...

Psychologically
calming effects
Aesthetics or
appearance
Protecting
human health
Improving
property value

226 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 227 5 Planning Setting Appendix G Appendix G
City of La Mesa Urban Forest Management Plan Survey
Q7 Of the following options, select the top TWO threats facing trees in your neighborhood.

Answered: 113 Skipped: 3
Drought
Unwanted by
property owner
Conflicts with
other...

Pests and
diseases
Climate change
Increasing
hi
City of La Mesa Urban Forest Management Plan Survey

71.76%
61 28.24%
24 85

40.35%
23 59.65%
34 57

52.00%
13 48.00%
12 25

40.00%
10 60.00%
15 25

16.67%
2 83.33%
10 12

16.67%
1 83.33%
5 6

20.00%
1 80.00%
4 5

MOST IMPORTANT SECOND MOST IMPORTANT TOTAL
Improving the environment (like air quality, water pollution) Cooling neighborhoods and homes
Psychologically calming effects
Aesthetics or appearance
Protecting human health
Improving property value
Traffic calming

228 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 229 5 Planning Setting Appendix G Appendix G
City of La Mesa Urban Forest Management Plan Survey

50.98%
26 49.02%
25 51

39.22%
20 60.78%
31 51

56.52%
26 43.48%
20 46

45.45%
15 54.55%
18 33

68.00%
17 32.00%
8 25

60.00%
9 40.00%
6 15

MOST IMPORTANT SECOND MOST IMPORTANT TOTAL
Drought
Unwanted by property owner
Conflicts with other infrastructure
Pests and diseases
Climate change
Increasing home sizes
8 / 27
Most Important Second Most Important
Unwanted by
property owner
Conflicts with
other...

Pests and
diseases
Climate change
Increasing
home sizes
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

230 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 231 5 Planning Setting Appendix G Appendix G
City of La Mesa Urban Forest Management Plan Survey

41.82% 46

25.45% 28

20.00% 22

6.36% 7

6.36% 7
Q9 I would support a tree ordinance that would require a tree to be planted on a single-family home property if the owner decides to redevelop the property to increase the size of the home.

Answered: 110 Skipped: 6
TOTAL 110
Strongly agree
Agree
Somewhat agree
Disagree
Strongly
disagree
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

ANSWER CHOICES RESPONSES
Strongly agree
Agree
Somewhat agree
Disagree
Strongly disagree
City of La Mesa Urban Forest Management Plan Survey

30.97% 35

53.10% 60

8.85% 10

7.08% 8
Q8 How often should a tree be watered in the first year after it’s planted? Answered: 113 Skipped: 3
TOTAL 113
Three times
per week
One time per
week
Every other
week
Once a month
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

ANSWER CHOICES RESPONSES
Three times per week
One time per week
Every other week
Once a month

232 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 233 5 Planning Setting Appendix G Appendix G
City of La Mesa Urban Forest Management Plan Survey

49.09% 54

27.27% 30

17.27% 19

3.64% 4

2.73% 3
Q11 The City should have ordinances requiring commercial (multi-family and business) properties to prune and maintain trees to an industry standard adopted by the City.

Answered: 110 Skipped: 6
TOTAL 110
Strongly agree
Agree
Somewhat agree
Disagree
Strongly
disagree
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

ANSWER CHOICES RESPONSES
Strongly agree
Agree
Somewhat agree
Disagree
Strongly disagree
City of La Mesa Urban Forest Management Plan Survey

29.09% 32

15.45% 17

29.09% 32

19.09% 21

7.27% 8
Q10 The City should have ordinances to protect trees on private property in the same way they protect trees in the public space.

Answered: 110 Skipped: 6
TOTAL 110
Strongly agree
Agree
Somewhat agree
Disagree
Strongly
disagree
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

ANSWER CHOICES RESPONSES
Strongly agree
Agree
Somewhat agree
Disagree
Strongly disagree

234 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 235 5 Planning Setting Appendix G Appendix G
City of La Mesa Urban Forest Management Plan Survey

49.09% 54

27.27% 30

17.27% 19

3.64% 4

2.73% 3
Q11 The City should have ordinances requiring commercial (multi-family and business) properties to prune and maintain trees to an industry standard adopted by the City.

Answered: 110 Skipped: 6
TOTAL 110
Strongly agree
Agree
Somewhat agree
Disagree
Strongly
disagree
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

ANSWER CHOICES RESPONSES
Strongly agree
Agree
Somewhat agree
Disagree
Strongly disagree
City of La Mesa Urban Forest Management Plan Survey

29.09% 32

15.45% 17

29.09% 32

19.09% 21

7.27% 8
Q10 The City should have ordinances to protect trees on private property in the same way they protect trees in the public space.

Answered: 110 Skipped: 6
TOTAL 110
Strongly agree
Agree
Somewhat agree
Disagree
Strongly
disagree
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

ANSWER CHOICES RESPONSES
Strongly agree
Agree
Somewhat agree
Disagree
Strongly disagree

236 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 237 5 Planning Setting Appendix G Appendix G
City of La Mesa Urban Forest Management Plan Survey

5.50% 6

35.78% 39

48.62% 53

10.09% 11
Q13 Which of the following is the most effective way to educate residents of La Mesa on the value of trees to the City?
Answered: 109 Skipped: 7
TOTAL 109
Online
trainings
Information
mailed to th...

Social media
Print media
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

ANSWER CHOICES RESPONSES
Online trainings
Information mailed to the home
Social media
Print media
City of La Mesa Urban Forest Management Plan Survey

50.00% 55

25.45% 28

14.55% 16

6.36% 7

3.64% 4
Q12 The City should have ordinances requiring parking lots on commercial (multi-family and business) properties to maintain a canopy cover that meets sustainability goals of the City.

Answered: 110 Skipped: 6
TOTAL 110
Strongly agree
Agree
Somewhat agree
Disagree
Strongly
disagree
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

ANSWER CHOICES RESPONSES
Strongly agree
Agree
Somewhat agree
Disagree
Strongly disagree

238 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 239 5 Planning Setting Appendix G Appendix G
City of La Mesa Urban Forest Management Plan Survey

49.54% 54

40.37% 44

7.34% 8

1.83% 2

0.92% 1
Q15 Rate your reaction to the following statement: Homeowners should be encouraged to increase the number of healthy trees on their property.

Answered: 109 Skipped: 7
TOTAL 109
Strongly agree
Agree
Somewhat agree
Disagree
Strongly
disagree
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

ANSWER CHOICES RESPONSES
Strongly agree
Agree
Somewhat agree
Disagree
Strongly disagree
City of La Mesa Urban Forest Management Plan Survey

28.04% 30

13.08% 14

15.89% 17

42.99% 46
Q14 Which of the following activities would you be willing to participate in support the City’s tree canopy goals?
Answered: 107 Skipped: 9
TOTAL 107
Volunteer tree
planting
Educational
workshop
Walking tour
of significa...

Planting a
tree on my...
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

ANSWER CHOICES RESPONSES
Volunteer tree planting
Educational workshop
Walking tour of significant trees
Planting a tree on my private property

240 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 241 5 Planning Setting Appendix G Appendix G
City of La Mesa Urban Forest Management Plan Survey

38.38% 38

61.62% 61
Q17 Do you work in La Mesa?
Answered: 99 Skipped: 17
TOTAL 99
Yes
No
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

ANSWER CHOICES RESPONSES
Yes
No
City of La Mesa Urban Forest Management Plan Survey
Q16 Do you have any other additional comments?
Answered: 48 Skipped: 68

242 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 243 5 Planning Setting Appendix G Appendix G
City of La Mesa Urban Forest Management Plan Survey

25.25% 25

16.16% 16

7.07% 7

15.15% 15

13.13% 13

11.11% 11

12.12% 12
Q19 Select the zone in which you live.

Answered: 99 Skipped: 17
TOTAL 99
Zone 1
Zone 2
Zone 3
Zone 4
Zone 5
Zone 6
Zone 7
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

ANSWER CHOICES RESPONSES
Zone 1
Zone 2
Zone 3
Zone 4
Zone 5
Zone 6
Zone 7
City of La Mesa Urban Forest Management Plan Survey

92.93% 92

7.07% 7
Q18 Do you live in La Mesa?
Answered: 99 Skipped: 17
TOTAL 99
Yes
No
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

ANSWER CHOICES RESPONSES
Yes
No

244 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 245 5 Planning Setting Appendix G Appendix G
City of La Mesa Urban Forest Management Plan Survey

81.82% 81

17.17% 17

0.00% 0

1.01% 1
Q21 Which of the following best describes your current housing situation Answered: 99 Skipped: 17
TOTAL 99
Homeowner
Renter
Living with
others, but ...

Living with
others, and...
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

ANSWER CHOICES RESPONSES
Homeowner
Renter
Living with others, but not paying rent or mortgage
Living with others, and paying a portion of rent or mortgage City of La Mesa Urban Forest Management Plan Survey

82.83% 82

3.03% 3

7.07% 7

6.06% 6

1.01% 1
Q20 What best describes your housing type?
Answered: 99 Skipped: 17
TOTAL 99
Single-family
home
Duplex
Condominium
Apartment
Other
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

ANSWER CHOICES RESPONSES
Single-family home
Duplex
Condominium
Apartment
Other

246 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 247 5 Planning Setting Appendix G Appendix G
City of La Mesa Urban Forest Management Plan Survey

75.00% 72

2.08% 2

0.00% 0

5.21% 5

3.13% 3

4.17% 4

16.67% 16
Q23 Are you White, Black or African-American, American Indian or Alaskan Native, Asian, Native Hawaiian or other Pacific islander? [Check all that apply].

Answered: 96 Skipped: 20
Total Respondents: 96
White
Black or
African-Amer...

American
Indian or...

Asian
Native
Hawaiian or...

Other
Prefer not to
say
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

ANSWER CHOICES RESPONSES
White
Black or African-American
American Indian or Alaskan Native
Asian
Native Hawaiian or other Pacific Islander
Other
Prefer not to say
City of La Mesa Urban Forest Management Plan Survey

73.74% 73

6.06% 6

0.00% 0

0.00% 0

3.03% 3

17.17% 17
Q22 Are you of Hispanic, Latino, or Spanish origin?
Answered: 99 Skipped: 17
TOTAL 99
I am not
Spanish,...

Yes; Mexican,
Mexican-Amer...

Yes; Puerto
Rican
Yes; Cuban
Yes; another
Spanish,...

Prefer not to
say
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

ANSWER CHOICES RESPONSES
I am not Spanish, Hispanic, or Latino
Yes; Mexican, Mexican-American, Chicano
Yes; Puerto Rican
Yes; Cuban
Yes; another Spanish, Hispanic, or Latino origin
Prefer not to say

248 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 249 5 Planning Setting Appendix G Appendix G
City of La Mesa Urban Forest Management Plan Survey

0.00% 0

1.02% 1

14.29% 14

9.18% 9

38.78% 38

36.73% 36
Q25 What is the highest level of education you have completed or the highest degree you have received?
Answered: 98 Skipped: 18
TOTAL 98
Less than high
school degree
High school
degree or...

Some college,
but no degree
Associate
degree
Bachelor degree
Graduate degree
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

ANSWER CHOICES RESPONSES
Less than high school degree
High school degree or equivalent (e.g., GED)
Some college, but no degree
Associate degree
Bachelor degree
Graduate degree

250 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 251 5 Planning Setting Appendix H

APPENDIX H
Funding the Urban Forest
Appendix H
Funding the Urban Forest
Maintaining La Mesa’s urban forest is an
investment in the sustainability of the trees
as well as health and safety of the residents,
visitors, and the environment. The benefits
of urban forests are discussed in detail
throughout this UFMP, such as greenhouse
gas reductions, increased health benefits,
environmental justice, and water and energy
conservation. Maintaining healthy trees and
increasing urban forest canopy cover leads
to increased benefits. Each dollar invested in
La Mesa’s urban forest will be reflected in a
realized environmental and economic benefit
to the City.

Often, funding for municipal urban forest
programs is reduced during times of financial
downturn, to maintain funding levels for other
city services such as the police department,
fire department, road projects, schools,
and other public services. As a result, tree
maintenance budgets are often at risk for
reductions (Voght et al. 2015). As outlined in
Table H-1, there are various costs associated
with maintaining the urban forest. It should
also be noted that costs associated with
deferred maintenance of the urban forest can
be even greater. For example, Browning and
Wiant (1997) found that deferring utility tree
pruning 4 years past the optimal pruning cycle
(5–7 years) yielded $1.47 to $1.69 in costs for
every $1 deferred, and resulted in a two-fold
increase in pruning debris. In another study,
Ryder and Moore (2013) found that pruning
Table H-1. Costs Associated with Urban Forests
Cost Examples
Direct costs Planting, pruning, watering, and other types of maintenance Infrastructure conflict costs Pavement and sewer repair, blockage of signs, tree-initiated power outages Externally related costs Emissions of biogenic volatile organic compounds, release of carbon dioxide during decomposition, allergies due to pollen release,
leaf/debris cleanup
Chapter 24.09 Scenic Preservation Overlay Zone
Chapter 24.10 Brier Tract Overlay Zone
Chapter 24.17 Bowling Green Overlay Zone
Chapter 24.18 Mixed Use Overlay Zone
Opportunity costs Space for trees cannot be used for parking, bike lanes, etc.

Staff time Salary and benefits for staff and laborers associated with urban forest management and maintenance.

Source: Adapted from Voght et al. 2015.

252 | CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN CITY OF LA MESA – URBAN FOREST MANAGEMENT PLAN | 253 5 Planning Setting Appendix H Appendix H
trees at a young age (formative pruning)
was less expensive than waiting to correct
structural defects 20 years later. Ultimately,
the cost of not maintaining the urban forest
is much greater than sustainably funding the
urban forest. Table H-2 presents funding
opportunities that the City could consider
pursuing to increase monetary resources
allocated to the urban forest.

Table H-2. Funding Opportunities
Grants
Environmental
Enhancement Mitigation
Program (California Natural
Resources Agency)
With approximately $13.4 million for the 2021–2023 funding cycle, this program encourages projects that produce multiple benefits that reduce greenhouse gas emissions; increase water use efficiency; reduce risks from climate change impacts; and demonstrate collaboration with local, state, and community entities. Eligible projects like tree planting and habitat restoration, must be directly or indirectly related to the environmental impact of the modification of an existing transportation facility or construction of a new transportation facility.

Urban Flood Protection
Grant Program (California
Natural Resources Agency)
The Urban Flood Protection Program was created by Proposition 68 for the purpose of multi-benefit projects in urbanized areas to address flooding. Projects must provide multi-benefit solutions to address flooding in urban areas, protect people, and protect property from flood damage. Examples of eligible projects include tree planting and establishment care and creating native landscapes with stormwater capture features like bioswales. There was one funding cycle for fiscal year 2020–2021 totaling $92.5 million.

Urban and Community
Forestry Program (CAL
FIRE)
Multiple grant programs supported by the Urban and Community Forestry Program will fund tree planting, tree inventories, urban wood and biomass utilization, blighted urban lands improvements, and leading-edge work that advances the goals and objectives of supporting healthy urban forests and reducing greenhouse gas emissions. There was an estimated $29.9 million available to fund a variety of urban forestry projects in fiscal year 2021-2022.

Urban Greening Grant
Program (California Natural
Resources Agency)
Consistent with Assembly Bill 32 (2006), the Urban Greening Program will fund urban greening and urban forestry projects that reduce greenhouse gases by sequestering carbon, decreasing energy consumption, and reducing vehicles miles traveled, while also transforming the built environment into places that are more sustainable, enjoyable, and effective in creating healthy and vibrant communities. Approximately $47.5 million are available for the 2022 grant application cycle.

Grants
Active Transportation
Program (California
Department of
Transportation)
This program provides funding to encourage increased use of active modes of transportation, such as biking and walking.

Trees and other vegetation are significant components of several eligible projects under the Active Transportation Program, including parks, trails, and safe routes to schools. $440 million will be distributed to project applicants over fiscal years 2019–2020, 2020–2021, 2021–2022, and 2022–2023. Applicants include public agencies, transit agencies, school districts, tribal governments, and nonprofit organizations.

Affordable Housing and
Sustainable Communities
(California Strategic Growth
Council)
The Strategic Growth Council is authorized to fund land use, housing, transportation, and land preservation projects to support infill and compact development that reduce greenhouse gas emissions. Urban Greening is a threshold requirement for all Affordable Housing and Sustainable Communities funded projects. Eligible urban greening projects include, but are not limited to, rainwater recycling; flow and filtration systems including rain gardens, stormwater planters, and filters; vegetated swales; bioretention basins; infiltration trenches; and integration with riparian buffers, shade trees, community gardens, and parks and open space. Funding for 2021 is estimated at $452 million and will be available to locality (e.g., local agencies), developer (entity responsible for project construction), or program operator (day-to-day operational project administrator) project applicants.

Parcel Tax
A parcel tax is a special tax levied for the provision of special benefits. Revenues from special taxes must be used for the specific purpose for which they are intended, so a parcel tax could create a dedicated funding stream for street trees.

Similar to a special assessment, a parcel tax cannot be based on the value of property; however, the amount levied on each parcel need not be directly related to the benefits provided (ILG 2008). Cities have the flexibility to levy parcel taxes as they see fit, but they are typically based on lot square footage or levied as a flat tax, with the same amount per parcel. Parcel taxes are designed to encompass entire cities and therefore, are good candidates for a citywide street tree program, as opposed to the district-level approach that often occurs under special assessments.

Landscape and Lighting
Assessment Districts
Landscape and Lighting Assessment Districts (LLADs) are a form of special assessment that finance improvements to landscaping, lighting and open space, along with open space acquisition. The Landscape and Lighting Act of 1972 authorizes municipal agencies in California to initiate and administer LLADs. The creation of a LLAD, as with any special assessment, requires the preparation of an Engineer’s Report that demonstrates the nexus between fees assessed and benefits provided, followed by majority (50 percent plus one) approval via a special ballot, pursuant to Proposition 218.

LLADs are widely used throughout California to fund a range of public realm improvements and services related to street trees, streetscape improvements, street and traffic lights, and recreational facilities, among others. As with parcel taxes, LLADs typically fund more than just street tree planting, establishment and maintenance. While a LLAD could be designed for street trees alone, the process may attract other agencies in need of additional revenue and interested in expanding the scope to services such as park and recreation maintenance. One caution would be to avoid setting the assessment so high as to generate voter backlash. Local municipalities have often convened focus groups to determine the appropriate assessment level.