FENCES AND LANDSCAPING
The Pomona Guide to Historic Preservation
Attachment No. 3
5-2
PRESERVING POMONA
CITY OF POMONA
CITY COUNCIL
Tim Sandoval, Mayor
Steve Lustro, Vice Mayor
John Nolte, Councilmember
Victor Preciado, Councilmember
Nora Garcia, Councilmember
Elizabeth Ontiveros-Cole, Council Member
Robert Torres, Council Member
HISTORIC PRESERVATION COMMISSION
Chara Swodeck, Chairperson
Tamara Gonzalez, Vice Chairperson
James Gallivan, Commissioner
Alice R. Gomez, Commissioner
Jim Kercheval, Commissioner
Ann Tomkins, Commissioner
Marcos Molina, Commissioner
Jennifer Williams, Former Commissioner
CITY ADMINISTRATION
James Makshano ff , City Manager
DEVELOPMENT SERVICES AND PLANNING DIVISION STAFF
Anita D. Gutierrez, AICP, Development Services Director Ata Khan, Planning Manager
Geo ff rey Starns, AICP, LEED AP BD+C, Historic Preservation Supervisor Vinny Tam, AICP, Senior Planner
Alex Jimenez, Associate Planner
Alina Barron, Associate Planner
Lynda Ramos, Associate Planner
Alan Fortune, Assistant Planner
Carlos Molina, Assistant Planner
Irene Aceituno, Planning Technician
Karina Diaz, Planning Technician
Alejandra Guzman-Bracamontes, Public Health Fellow
Monica Montanez, Community Health Worker
Jocelyn Ayala, Arts Coordinator
Lina Do, Planning Intern
Zully Villegas, Planning Intern
Nancy Garcia, Administrative Assistant
Miroslava PourSanae, Administrative Assistant
REVISION LIST
ADOPTED ON NOVEMBER 2, 2022
The Pomona Guide to Historic Preservation
5-3 CHAPTER 5: HISTORIC LANDSCAPES
CHAPTER 5:
FENCES AND LANDSCAPES
FENCES 5-3
TREE PRESERVATION 5-17
GENERAL LANDSCAPING 5-65
LAWN ALTERNATIVES 5-69
HL
In previous chapters, we discuss the architecture of Pomona, the inside and outside of historic structures and new development in our historic neighborhoods. This chapter completes coverage of an historic property by providing guidelines and design standards for fences, tree preservation, and landscaping.
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5-5 CHAPTER 5: HISTORIC LANDSCAPES
FENCES AND WALLS
Fences and landscaping go together in adding to or detracting from the character of an historic building. The wrong fence without landscaping can make a building look like a prison, aff ecting not just the property, but also the entire neighborhood. A good fence with appropriate landscaping can enhance the architecture of the building. For example, a white picket fence in front of a Colonial Revival style home can create a garden cottage feeling. The fences portion of this Chapter also includes some landscaping requirements, generally, as it relates to fences. 5-6
PRESERVING POMONA
FENCE LOCATIONS
DESIGN STANDARDS FOR FENCE LOCATIONS
• For residential properties, fences are allowed in the front yard, side yard, street side yard, and rear yard.
• For non-residential properties, fences are allowed in the rear (not including through lots) and side yards. Fences are not allowed in any yard facing a street. • There is an exception to this rule for schools and properties with historic fencing in these locations.
Fence in non-residential historic building are only allowed in areas generally considered “non- public”, the rear and side yards. The intent of street facing yards is to provide an inviting space for the public, not to have a non-residential building surrounded by a fence.
AREA FENCES ARE ALLOWED (CHECK FOR HEIGHT
LIMITS )
1 1
1 COMMERCIAL
RESIDENTIAL
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5-7 CHAPTER 5: HISTORIC LANDSCAPES
FENCE SETBACKS
DESIGN STANDARDS FOR FENCE SETBACKS
• There is no required setback on an interior side or interior (or alley facing) rear property line
• There is a two (2) foot setback required for front yard and street side yard fences.
• The front yard and street side yard setbacks shall be landscaped.
While there are no setbacks for the side and rear property lines, there are setbacks for front yard fencing. The two (2) foot setback for front yard and street side yard fences allows enough room to create a landscape bu ff er between the fence and the sidewalk. This will also provide some defensible space between people on the sidewalk and someone on the inside of the fence.
PRIVACY FENCE
FRONT YARD FENCE
2 FOOT SETBACK AREA
2 1
2 3
3 1
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PRESERVING POMONA
FENCE MAXIMUM HEIGHTS
DESIGN STANDARDS FOR FENCE HEIGHTS
• A fence on the side and rear property lines has a maximum height limit of six (6) feet.
• A fence on a street side yard, behind the front yard has a maximum height limit of six (6) feet.
• A fence in the front yard has a maximum height limit of three (3) feet. • A fence that is 50% open has a maximum height of four (4) feet with Commission approval
A six (6) foot tall fence or wall has become a standardized height. It provides privacy without creating a hazard. In the front yard, solid walls and fences are allowed to be three (3) feet in height, which provides some security will still allowing the house to be seen from behind the fence. This allows the building to remain the focus. Any higher and the fence would limit visibility, creating safety concerns for fi rst responders. The Zoning Code allows fences and walls that are a minimum of 50% open (visually, can be seen through) can be up to four (4) feet in height. To exceed the three (3) feet in height for an open fence requires Commission approval. 6 FT PRIVACY FENCE
3 FT FRONT YARD FENCE2
1 2
1 1
COMMERCIAL
RESIDENTIAL
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5-9 CHAPTER 5: HISTORIC LANDSCAPES
FENCE DESIGN
DESIGN STANDARDS FOR FENCE DESIGN
• A fence design and material must meet the fence style appropriate to the building’s style of architecture as shown in the wall types on the following pages.
• Vinyl Fences are prohibited.
• Any fence not meeting this requirement requires approval by the Historic Preservation Commission.
The City of Pomona has taken the most common fence and wall types and determined which styles of architecture are appropriate for each wall type. Each wall type discusses the wall, its construction, and its design features. It also discusses variations due to the diff ering architectural styles.
HEDGES AND SIMILAR LANDSCAPE FEATURES
According to the Pomona Zoning Code, hedges and other types of Landscaping that creates a screen is considered a fence or wall and is subject to the same standards for location, setbacks, and height.
3 ft.
3 ft.
FRONT YARD PLANTINGS THAT EXCEED HEIGHT LIMIT
- NOT ACCEPTABLE
FRONT YARD HEDGE THAT MEETS HEIGHT LIMITS
- ACCEPTABLE
2 1
2 1
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PRESERVING POMONA
TYPE 1 – STUCCO WALL
DESIGN REQUIREMENTS FOR STUCCO WALL
• Stucco fi nish over block required.
• Finish must match the building
• Exposed block is prohibited.
• Cap treatment required (See Below).
• Footing cannot encroach into required setback.
ARCHITECTURAL STYLE CAP STYLE
Vernacular Adobe Architecture TC, RC
Mission Revival Architecture TC, BC
Beaux Arts Architecture PC
Monterey Revival Architecture TC, RC
Late Gothic Revival Architecture PC, BC *
French Provincial Revival Architecture BC, PC, RC**
Prairie Architecture PC
Mediterranean Revival Architecture TC, RC
Spanish Colonial Revival Architecture TC RC
CAP STYLE
TC: Terra Cotta Tile
RC: Rounded Stucco Top
BC: Brick Cap
PC: Precast Concrete Cap
* (if Brick is on Building)
** (if similar to features on Building)
The stucco fi nish is also important and must match the building. This is typically a smooth plaster fi nish, which was the most common fi nish prior to World War II, instead of a sand fi nish, which is more common today.
CAP STYLES
• Terra Cotta Tile
• Rounded Stucco Top
• Brick Cap
• Precast Concrete Cap
Stucco walls can be appropriate for numerous architectural styles. The Spanish infl uenced styles will use a terra cotta cap or wrap the stucco over the top of the wall, rounding the corners and having no cap. Other styles would typically use a precast concrete cap. A brick cap can only be used if the building also has exposed brick on it. The top of the walls are usually straight, but in conjunction with a decorative feature such as a fountain, they may uses a slight mission arch to emphasize the decorative feature.
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CONCRETE BLOCK (CMU)
METAL LATHE
1/4 IN. THICK SCRATCH COAT
1/2 IN. BROWN COAT
FINISH COAT
2 1
3 4
5 2
1 3
4 5
TERRA COTTA TILE CAP - TYPICALLY A 12" X 12" TILE 2" THICK
ROUNDED STUCCO TOP - STUCCO ON SIDE OF WALL USED ON
TOP . LATHE WRAPS OVER THE TOP AND STUCCO APPLIED
SAME AS SIDES.
BRICK CAP - COMMON TO USE ROMAN BRICK 12" X 4" X 2"
THICK
PRECAST CONCRETE CAP - COMMON IS A SQUARE EDGE 2"
OR 3" THICK CAP . DECORATIVE EDGING POSSIBLE, BUT MUST FIT WITH THE STYLE OF BUILDING.
7 6
8 9
7 6
8 9
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PRESERVING POMONA
DECORATIVE DETAILS
The Spanish in fl uenced styles, especially Spanish Colonial Revival, may also have decorative tiles as part of the stucco wall. The design can vary from a few tiles on columns to entire sections of wall covered in tile. This type of treatment usually coincides with other features such as lighting, fountains, or covered patios. If you are interested in a design treatment using tiles, contact Planning sta ff . They can help you design an appropriate wall.
TRADITIONAL MISSION ARCH ON BUILDING
MODIFIED MISSION ARCH USED ON WALLS AND
FOUNTAINS
MISSION ARCH USED AS PART OF WALL FOUNTAIN
FOUNTAIN BASIN WITH TERRA COTTA CAP
2 1
3 4
21 3
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CHAPTER 5: HISTORIC LANDSCAPES
Concrete walls are not appropriate for residential development. They typically incorporate columns to provide some depth and variation in height. Many of these styles would also incorporate wrought iron into their fence designs. Except for the Art Deco style, these walls would be very simple, with a concrete cap that would match the features on the building. Art Deco Walls would be highly decorative, using the same motifs in the wall as on the building.
TYPE 2 – CONCRETE WALL
DESIGN REQUIREMENTS FOR CONCRETE WALL
• Walls must be painted
• Finish must match the building
• Exposed concrete is prohibited.
• Cap treatment must match building.
• Footing cannot encroach into required setback.
APPROPRIATE ARCHITECTURAL STYLES
Art Deco Architecture
Streamline Moderne Architecture
Mid-Century Modern Architecture
Googie Architecture
Brutalism Architecture
New Formalism Architecture
2 ft.
COLUMN CAP
COLUMN BASE
WALL
FOOTING - USE AN OFFSET FOOTING TO AVOID SETBACK
AREA
SETBACK AREA
2 1
3 4
2 1
3 4
5 5
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PRESERVING POMONA
TYPE 3 – BRICK OR STONE WALL
DESIGN REQUIREMENTS FOR BRICK OR STONE WALL
• Material (stone, brick, etc.) must match material used on building • Cap treatment required
• Footing cannot encroach into required setback.
APPROPRIATE ARCHITECTURAL STYLES
Mission Revival Architecture
Tudor Revival Architecture
Late Gothic Revival Architecture
Prairie Architecture
French Provincial Revival Architecture
Monterey Revival Architecture
2 ft.
COLUMN CAP
COLUMN BASE
WALL
WALL CAP
FOOTING - USE AN OFFSET FOOTING TO AVOID SETBACK
AREA
SETBACK AREA
2 1
3 4
5 6
2 1
3 4
2 1
3 4
5 6
RIVER ROCK WALL
BRICK WALL
Brick and stone walls are rare in Pomona. They are appropriate for styles that use brick or stone as the primary construction material. Cap treatments are typically a precast or poured-in-place concrete. A decorative brick treatment can be used as a cap treatment on a brick wall.
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TYPE 4 - WROUGHT IRON / CAST IRON FENCING
DESIGN REQUIREMENTS FOR IRON FENCE
• Columns of Brick or Stone are appropriate to be use if material is on building • Variety of styles appropriate
• Pickets style typical on Victorian Era styles
• Decorative tops for Spanish Colonial, Mediterranean, and Mission Revival styles
APPROPRIATE ARCHITECTURAL STYLES
Italianate Architecture
Late Carpenter’s Gothic Revival Architecture
French Second Empire Architecture
Richardsonian Romanesque Architecture
Eastlake Architecture
Queen Anne Architecture
Victorian Vernacular Architecture
Mission Revival Architecture
Prairie Architecture
Mediterranean Revival Architecture
Spanish Colonial Revival Architecture
Art Deco Architecture
Streamline Moderne Architecture
Mid-Century Modern Architecture
Googie Architecture
Brutalism Architecture
New Formalism Architecture
Iron fencing became popular in the mid to late 1800s as cast iron was developed.
It was used on a variety of Victorian styles. By the early 1900s, wrought iron began replacing cast iron. Victorian styles began using wrought iron designs similar to the old cast iron designs. In addition, it became the choice for fences and gates for Spanish infl uenced styles of architecture. The Art Deco style (and to a smaller extent the Streamline Moderne style) began to use cut metal (usually steel sheets) to create decorative fencing that matched or complimented the ornate details on the buildings. Modernism brought forth the simpli fi ed iron fence that we see today. The issue with these types of fences is that designs are limited, which may be an issues for styles that should have a highly decorative fence. 5-16
PRESERVING POMONA
DECORATIVE PICKETS
TOP RAIL
BOTTOM RAIL
SUPPORTING RAILS
DECORATIVE IRON BETWEEN PICKETS
2 1
3 4
5 VICTORIAN ERA FENCES
SPANISH INFLUENCED FENCES
2 1
3 4
2 1
3 4
5 5
5 2
3 4
2 3
4 VICTORIAN ERA FENCING
Victorian Era Fencing is highly decorative and uses various architectural motifs. The posts between panels, at changes in direction, are much wider and resemble interior stair newelposts (at the base of the stairs). This style of fencing adds decoration to the pickets, showcasing the welding
ability of the craftsman.
SPANISH INFLUENCED FENCING
Spanish In fl uenced Fencing typically adds decorative
peices to a basic stratight fence panel. The Spanish
wrought iron tend to focus on more gentle slopes and
spirals that showcase the skill and ability of the craftsman to bend the iron.
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CHAPTER 5: HISTORIC LANDSCAPES
TYPE 5 – WOOD FENCE
DESIGN REQUIREMENTS FOR WOOD FENCE
• Picket / top treatment must be appropriate to architectural style (see below) • Front Yard fences must have a minimum spacing of 1 inch between boards • Privacy Fences do not require spacing between boards
APPROPRIATE ARCHITECTURAL STYLES TOP
Italianate Architecture TP
Late Carpenter’s Gothic Revival Architecture TP
French Second Empire Architecture TP
Richardsonian Romanesque Architecture TP
Eastlake Architecture TP
Queen Anne Architecture TP
Victorian Vernacular Architecture TP
Colonial Revival Architecture TP
Dutch Colonial Revival Architecture TP
Craftsman Architecture FT, BR
Late Gothic Revival Architecture TP
Bungalow Architecture FT, BR
Neoclassical Architecture TP
Prairie Architecture FT, BR
Tudor Revival Architecture FT, BR
Minimal Traditional Architecture FT, BR, HZ, DE
California Ranch Architecture FT, BR, HZ, DE
Early Post-War Tract Architecture FT, BR, HZ, DE
TOP STYLE
TP: Traditional Picket
FT: Flat Top
BR: Beam/Top Rail
HZ: Horizontal
DE: Dog-eared
TRADITIONAL PICKET - THE TRADITIONAL VICTORIAN / COLONIAL PICKET
FLAT TOP BOARD - BOARDS THAT DO N'T HAVE A TRADITIONAL PICKET AT
THE TOP OR BOTTOM
BEAM / TOP RAIL - THE BOARDS ARE SANDWICHED BETWEEN THE TOP
AND BOTTOM RAILS INSTEAD OF ATTACHING TO ONE SIDE TO THE TOP
AND BOTTOM RAIL
2 1
4 3
21 5
43 5
HORIZONTAL - BOARDS ATTACHED TO A FRAME HORIZONTALLY
RATHER THAN THE TRADITIONAL VERTICAL WAY.
DOG-EARED - REGULAR FENCE BOARDS WITH THE TOP CORNERS
CUT OFF (CHAMFERED )
Wood fencing has been used for hundreds of years in American. It became more popular in California after statehood and Victorian in fl uences became more popular. Victorian Era styles used a typical picket for front yard fences and a longer fence board with a picket at the top for privacy fences. Lattice Fences were also used. This style of fencing carried on into the Colonial Revival styles. Starting with the Craftsman style, fences got simpler. After World War II, the dog-eared wood fence became the most popular form of fencing.
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PRESERVING POMONA
TYPE 6 – SPLIT RAIL FENCE
DESIGN REQUIREMENTS FOR SPLIT RAIL FENCE
• Residential Property Only
• Meet height requirements for posts
• The top of the top rail must be a minimum 4 inches below the top of the post.
APPROPRIATE ARCHITECTURAL STYLES
Minimal Traditional Architecture
California Ranch Architecture
Early Post-War Tract Architecture
TYPICAL SPLIT RAIL FENCE . SPLIT RAIL REFERS TO THE SPACE
BETWEEN THE TOP AND BOTTOM RAILS
TOP RAIL
POST
BOTTOM RAIL
2 1
32 1
3 Split rail fencing is typically only used as a front yard fence on residential properties, as it does not provide privacy. It was used on non-residential properties. Typically, 2-3 rails are used for a 4-foot tall fence. A precast concrete split rail fence is becoming popular. Provided the concrete is integral color (part of the concrete and not painted), this is an acceptable alternative since the molds for the concrete create a wood appearance.
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GATES
Gates for the fence and wall types are typically constructed of wood, except for wrought iron fences, which use matching wrought iron gates. Spanish infl uenced walls may also use an iron gate. They will also typically use a round top gate, where other styles, such as craftsman and colonial, will use a rectangular shaped gate. Wood fences will typically use a gate that matches the fence.
WOOD GATE (FLAT TOP ACCEPTABLE FOR STYLES THAT
USE FLAT TOP FENCING )
WROUGHT IRON GATE - SPANISH INFLUENCED STYLES
ONLY
ADJACENT FENCE/WALL
2 1
3 2
1 3
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CHAPTER 5: HISTORIC LANDSCAPES
TREE PRESERVATION
Trees are one of the things in historic neighborhoods that residents identify with most. Residents are protective of their neighborhood trees. The City of Pomona recognizes that this is one of the features that give historic neighborhoods their character. The City also recognizes that trees are damaged and eventually die. The guidelines in this section relate to the care of trees and the process if a tree needs to be removed. The City of Pomona is committed to reforesting our historic districts, to protect the character of our neighborhoods and to provide environmental bene fi ts to the public.
Mature trees provide many bene fi ts to the public. They provide shade, which reduces the ambient temperature, and the heat on houses (up to 40 degrees), which reduces the need for air conditioning. The shade also makes the streets more walkable. Trees are also good for the environment by reducing the heat island e ff ect, cleaning the air, and sequestering carbon, which reduces the amount of greenhouse gases in the air.
PROTECTED TREES
The City of Pomona has, as part of the tree protection and preservation program, a protected species list. Any tree listed and meeting the minimum size (diameter) requires approval before it can be removed. Trees that are dead, diseased, or a danger to public welfare, may be approved by Staff . Healthy trees that are not dangerous may be removed with the approval of the Historic Preservation Commission.
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PRESERVING POMONA
TREE PROTECTION ZONES
The protected zone of a tree on historic properties is the area on the ground beneath the “dripline” or canopy of the tree. Any work proposed within the protected zone requires review to determine if the proposed work could a ff ect the tree, causing its death. Alterations to the proposed project may be necessary to protect the tree.
ROOT CUTTING
Great care needs to be taken when cutting roots within the dripline of a tree. cutting too many roots can cause the tree to die, or damage it to a point that it can fall.
IRRIGATION LINES NEAR TREES
Irrigation lines should be placed far enough from the tree to avoid existing and future tree roots.
Tree roots can break irrigation lines. This can reduce water pressure, and potentially cause the overwatering of the tree (See Over-Watering Below)
OVER-WATERING
Overwatering trees can cause severe damage to the roots of a tree. Over-watering can lead to root rot, which will damage the tree and make it more vulnerable to falling over in windy conditions.
WATERING STREET TREES
Property owners are required to water street trees in parkways in front of their property. Failure to water street trees could result in Code Enforcement Action. In addition, the City can water the trees and charge the property owner the cost of watering the trees.
TREE TRIMMING STANDARDS
The City of Pomona requires all trees to be trimmed using the ANSI 300 Pruning Standards.
Any tree not pruned to these standards could require the evaluation of the tree to determine if replacement of the tree is necessary. Any replacement would follow the City’s Replacement Methodology and would be considered retroactive for determination of the replacement amount.
The ANSI 300 Standards require an Arborist to oversee any trimming of a tree.
The ANSI 300 tree pruning standards are at the end of this chapter.
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TREE REPLACEMENT METHODOLOGY
The City of Pomona has developed a replacement methodology for trees that are approved for removal. The intention of the methodology is to replace a tree with a tree of equal replacement value. It is based on the type of tree proposed for removal, its size (diameter at breast height or dbh)(dbh is equal to 4 feet 6 inches), and the proposed replacement tree species.
The Replacement Methodology is as follows:
Tree Type x Heritage Tree x Retroactive Permit = Total Replacement Value Maximum Replacement Ratio is 8:1
TREE TYPE
Category 1:
1:1: Any tree replaced with the same species, a tree on the Preferred Tree List, or a tree similar in height and canopy size to the trees on the Preferred Tree List.
For trees not on the Preferred Tree List, City sta ff and the City Arborist will compare a proposed tree's characteristics with characteristics of the trees on the Preferred Tree List and use iTrees software to verify that the proposed tree is similar to trees on the preferred tree list.
Category 2:
2:1: Any tree replaced with a species that does not meet the Category 1 requirements. 5-24
PRESERVING POMONA
HERITAGE TREES
Any tree removed over twenty-four (24) inches in diameter shall be replaced at a rate double the rate specifi ed under Tree Type (2:1 replacement rate).
RETROACTIVE PERMITS
All applications asking for approval of a tree removed prior to approval is considered a Retroactive approval. Retroactive approval are replaced at double the combined rate of Tree Type and Heritage Tree rates (2:1 replacement rate).
EXAMPLES
The following examples illustrate how the replacement value will be calculated under the research methodology.
Example #1
Approval to replace a 20-inch London Plane tree to be replaced with a London Plane tree.
Tree Type: 1:1 (Same Tree Species)
Heritage Tree: N/A
Retroactive Permit: N/A
Total: 1:1
Example #2
Approval to replace a 28-inch American Sweet Gum tree to be replaced with a California Sycamore.
Tree Type: 1:1 (California Sycamore on Preferred List) Heritage Tree: 2:1
Retroactive Permit: N/A
Total: 2:1
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Example #3
Retroactive removal of a 30-inch diameter Camphor tree to be replaced with a Navel Orange tree.
Tree Type: 2:1
Heritage Tree: 2:1
Retroactive Permit: 2:1
Total: 8:1
MINIMUM TREE SIZE
Minimum tree size for replanting.
The city requires that any replacement tree be a minimum of 15-gallon tree. 5-26
PRESERVING POMONA
PREFERRED TREE LIST
The Preferred List consist of trees that have been identifi ed as trees that will grow well in Pomona’s climate, are drought tolerant, have good carbon sequestration, and are good shade trees. These trees are good for Pomona’s climate. They clean the air, provide shade that helps reduce the heat island eff ect, and help reduce the use of water. This list does not apply to street trees. The City has a separate Street Tree List that designates specifi c species to every street in the historic districts.
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PREFERRED TREE LIST SPECIES
Common Name Scienti fi c Name
Blackwood Acacia Acacia melanoxylon
Italian Alder Alnus cordat
Incense Cedar Calocedrus decurrens
Ironwood Casuarina equisetifolia
Carob tree Ceratonia silique
Arizona cypress Cupressus arizonica
Indian Rosewood Dalbergia sissoo
River red gum Eucalyptus camaldulensis
Red ironbark Eucalyptus sideroxylon
Majestic Beauty’ ash Fraxinus uhdei ‘Majestic Beauty’
Thornless Honey Locust Gleditsia tricanthos var. inermis Silk oak Grevillea robusta
Black walnut Juglans nigra
Fruitless mulberry Morus alba ‘Fruitless’
Torrey pine Pinus torreyana
Western cottonwood Populus fremontii ‘Nevada’
Carolina Laurel Cherry Prunus caroliniana
Carrot Wood Cupaniopsis anacardioides
Fruitless Olive Tree Olea europaea ‘Swan Hill”
Australian Willow Geijera parvi fl ora
Purple-leaf Acacia Acacia baileyana ‘Purpurea’
Goldenrain Tree Koelreuteria paniculata
Common Hackberry / Western Redbud Celtis occidentalis
Hollyleaf Cherry Prunus ilicifolia
Brisbane Box Lophostemon confertus
California Sycamore Platanus racemosa
Coast Live Oak Quercus agrifolia
POMONA PLANTING CHARACTERISTICS
The Sunset Western Garden Handbook has been one of the most trusted sources for gardening and planting information for over 80 years. Pomona is in the Sunset Western Garden Zone 18. All the trees in the Preferred Tree List can be planted in Zone 18.
We have also included for reference the USDA hardiness zones. The zones were created to help determine which plants are likely to thrive in a location. It is based on the average minimum winter temperature divided into 10-degree zones. Pomona is in either the USDA Hardiness Zone 9b or 10a depending on where in the City you are located.
TREE PHOTOS FROM SELECTREE, URBAN FOREST ECOSYSTEMS
INSTITUTE, CAL POLY SAN LUIS OBISPO
HTTP://UFEI.CALPOLY.EDU/
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PRESERVING POMONA
BLACKWOOD ACACIA
ACACIA MELANOXYLON
The Blackwood Acacia is native of Eastern Australia and grows best in well-drained fertile soil. It grows very fast and has a good canopy size.
Tree Type: Evergreen
Maximum Height: 50 feet
Canopy Width: 20 feet
Growth Rate: 36-127 inches per year
Sunset Western Garden Zones: 8-9, 13-24
USDA Hardiness Zones: 9, 10, and 11
Sun Exposure: Partial Shade to Full Sun
SelecTree Water Usage Rating (at Planting): Low
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CHAPTER 5: HISTORIC LANDSCAPES
ITALIAN ALDER
ALNUS CORDAT
The Italian Alder grows best with regular deep watering. Its roots can spread and be invasive if they are poorly watered. The tree is native to Italy and Corsica. It can be susceptible to Beetle Borers. This tree is not suitable in small areas such as side yards.
Tree Type: Deciduous
Maximum Height: 50 feet
Canopy Width: 25 feet
Growth Rate: 36-127 inches per year
Sunset Western Garden Zones: 2-9, 14-24
USDA Hardiness Zones: 5, 6, and 7
Sun Exposure: Partial Shade to Full Sun
SelecTree Water Usage Rating (at Planting): Medium
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INCENSE CEDAR
CALOCEDRUS DECURRENS
The Incense Cedar tree is a native to California. The tree grows slowly when fi rst planted, but the growth rate increases when established.
Tree Type: Evergreen
Maximum Height: 90 feet
Canopy Width: 10-15 feet
Growth Rate: 12-24 inches per year
Sunset Western Garden Zones: 2-12, 14-24
USDA Hardiness Zones: 5, 6, 7, and 8
Sun Exposure: Partial Shade to Full Sun
Selectree Water Usage Rating (at Planting): Medium
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IRONWOOD
CASUARINA EQUISETIFOLIA
The Ironwood tree is a fast-growing tree found throughout the Pacifi c Islands. It is native to French Polynesia, Australia, Malaysia, and Burma (Myanmar) Tree Type: Evergreen
Maximum Height: 65 feet
Canopy Width: 20 feet
Growth Rate: 36 inches per year
Sunset Western Garden Zones: 8-9, 12-24, H1, H2
USDA Hardiness Zones: 9, and 10
Sun Exposure: Partial Shade to Full Sun
Selectree Water Usage Rating (at Planting): Low
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PRESERVING POMONA
CAROB TREE
CERATONIA SILIQUE
The Carob Tree is known for being drought-tolerant. It is native to the Mediterranean region, making it suitable for California’s climate.
Tree Type: Evergreen
Maximum Height: 40 feet
Canopy Width: 30-40 feet
Growth Rate: 24 inches per year
Sunset Western Garden Zones: 9, 13-16, 18-24, H1, H2
USDA Hardiness Zones: 9-11
Sun Exposure: Partial Shade to Full Sun
Selectree Water Usage Rating (at Planting): Low
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ARIZONA CYPRESS
CUPRESSUS ARIZONICA
This species of Cypress is native to Central Arizona. It is drought tolerant and is suitable for California’s climate.
Tree Type: Evergreen
Maximum Height: 40 feet
Canopy Width: 20 feet
Growth Rate: 12-36 inches per year
Sunset Western Garden Zones: 7-24
USDA Hardiness Zones: 7-9
Sun Exposure: Full Sun
Selectree Water Usage Rating (at Planting): Low
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PRESERVING POMONA
INDIAN ROSEWOOD
DALBERGIA SISSOO
Native to India, the Indian Rosewood tree takes very little water to establish it, making it ideal for Pomona. It is a fast growing, large shade tree that will lose most, if not all its leaves in the winter. It has a spreading root system and thrives in lawns.
It is drought-tolerant.
Tree Type: Deciduous – Partly Deciduous
Maximum Height: 60 feet
Canopy Width: 30-40 feet
Growth Rate: 24-36 inches per year
Sunset Western Garden Zones: 13, 18, 19, 21-24
USDA Hardiness Zones: 9-11
Sun Exposure: Partial Shade to Full Sun
Selectree Water Usage Rating (at Planting): Very Low
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RIVER RED GUM
EUCALYPTUS CAMALDULENSIS
This evergreen tree is in the Eucalyptus family and is not appropriate in small areas.
It is drought-tolerant and native to Australia. It should have a large planting area (over 10 feet) for best results. It grows extremely fast, and is a very large shade tree, but can cause a litter problem with the bark and twigs.
Tree Type: Evergreen
Maximum Height: 150 feet
Canopy Width: 40-105 feet
Growth Rate: 36-127 inches per year
Sunset Western Garden Zones: 5-6, 8-24
USDA Hardiness Zones: 9-10
Sun Exposure: Partial Shade to Full Sun
Water Usage Rating (at Planting): Low
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PRESERVING POMONA
RED IRONBARK
EUCALYPTUS SIDEROXYLON
Another member of the Eucalyptus family this variety does not get as big as its cousin does, but is still a large shade tree. It is native of Eastern Australia.
Tree Type: Evergreen
Maximum Height: 90 feet
Canopy Width: 30-60 feet
Growth Rate: 36-127 inches per year
Sunset Western Garden Zones: 5-6, 8-24
USDA Hardiness Zones: 9-10
Sun Exposure: Partial Shade to Full Sun
Water Usage Rating (at Planting): Low
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MAJESTIC BEAUTY EVERGREEN ASH
FRAXINUS UHDEI ‘MAJESTIC BEAUTY’
This variety of Ash tree is large, fast growing shade tree. It is susceptible to root rot so be sure not to over water it.
Tree Type: Evergreen
Maximum Height: 80 feet
Canopy Width: 60 feet
Growth Rate: 36-127 inches per year
Sunset Western Garden Zones: 9, 12-24
USDA Hardiness Zones: 9-10
Sun Exposure: Partial Shade to Full Sun
Water Usage Rating (at Planting): Medium
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PRESERVING POMONA
THORNLESS HONEY LOCUST
GLEDITSIA TRICANTHOS VAR. INERMIS
This variety of Honey Locust is durable and adaptable to a variety of soil conditions.
It is the most commonly sold of the Honey Locust trees since it does not have the large thorns on its bark and stems. It is native to the Chicago Area.
Tree Type: Deciduous
Maximum Height: 60 feet
Canopy Width: 40 feet
Growth Rate: 36-127 inches per year
Sunset Western Garden Zones: 1-16, 18-20
USDA Hardiness Zones: 4-9
Sun Exposure: Partial Shade to Full Sun
Water Usage Rating (at Planting): Medium
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SILK OAK
GREVILLEA ROBUSTA
Native to Eastern Australia, the Silk Oak is one of about 360 species of Grevillea.
Its wood is similar in appearance to Oak, and is used in making furniture and other products, similar to an Oak tree. It is fast growing, large shade tree. A good local example of how big the trees can get is Euclid Avenue in Upland and Ontario. They are the parkway trees for the avenue.
Tree Type: Evergreen
Maximum Height: 150 feet
Canopy Width: 30-35 feet
Growth Rate: 36-127 inches per year
Sunset Western Garden Zones: 8-9, 12-24, H1, H2
USDA Hardiness Zones: 8-10
Sun Exposure: Full Sun
Water Usage Rating (at Planting): Low
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PRESERVING POMONA
BLACK WALNUT
JUGLANS NIGRA
The Black Walnut tree is native to Eastern North America. The tree is drought- tolerant and can handle both hot and cold weather. It can produce a toxin that is harmful to other plants. The toxin is at its greatest concentration at the dripline, so care should be taken when determining placement of the tree.
Tree Type: Deciduous
Maximum Height: 100 feet
Canopy Width: 70 feet
Growth Rate: 24 inches per year
Sunset Western Garden Zones: 1-9, 14-21
USDA Hardiness Zones: 5-9
Sun Exposure: Partial Shade to Full Sun
Water Usage Rating (at Planting): Medium
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FRUITLESS MULBERRY
MORUS ALBA ‘FRUITLESS’
The Fruitless Mulberry is a good yard shade tree since it does not get to big. It is fast growing and drought-tolerant.
Tree Type: Evergreen
Maximum Height: 30 feet
Canopy Width: 30-45 feet
Growth Rate: 36-127 inches per year
Sunset Western Garden Zones: 2-24
USDA Hardiness Zones: 3-9
Sun Exposure: Partial Shade to Full Sun
Water Usage Rating (at Planting): Medium
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PRESERVING POMONA
TORREY PINE
PINUS TORREYANA
Native to California, the Torrey Pine is found primarily in San Diego County. It is a fast growing tree.
Tree Type: Evergreen
Maximum Height: 50 feet
Canopy Width: 20-25 feet
Growth Rate: 36 inches per year
Sunset Western Garden Zones: 8-9, 14-24
USDA Hardiness Zones: 8-10
Sun Exposure: Partial Shade to Full Sun
Water Usage Rating (at Planting): Medium
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WESTERN COTTONWOOD
POPULUS FREMONTII ‘NEVADA’
Also known as the Fremont Cottonwood, the Western Cottonwood is a California native. It is most commonly found in riparian areas. It has an extensive root system so be sure it is away from buildings, underground pipes and sidewalks.
Tree Type: Deciduous
Maximum Height: 80 feet
Canopy Width: 30-50 feet
Growth Rate: 36 inches per year
Sunset Western Garden Zones: 1-12, 14-21
USDA Hardiness Zones: 3-9
Sun Exposure: Full Sun
Water Usage Rating (at Planting): High
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PRESERVING POMONA
CAROLINA LAUREL CHERRY
PRUNUS CAROLINIANA
The Carolina Cherry is a drought tolerant tree that can withstand dryness, winds, and heat. It is native to the Southeastern United States. Its litter can be a problem on paved areas.
Tree Type: Evergreen
Maximum Height: 30 feet
Canopy Width: 15-25 feet
Growth Rate: 36 inches per year
Sunset Western Garden Zones: 5-24
USDA Hardiness Zones: 7-10
Sun Exposure: Partial Shade to Full Sun
Water Usage Rating (at Planting): Medium
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CARROT WOOD
CUPANIOPSIS ANACARDIOIDES
The Carrot Wood withstands hot and dry winds. It is native to Australia and are a slow growing tree compared to others on this list. Some trees drop fruit, which can be a nuisance depending on the tree location. Some never produce any fruit.
Tree Type: Evergreen
Maximum Height: 40 feet
Canopy Width: 30 feet
Growth Rate: 12-24 inches per year
Sunset Western Garden Zones: 16-24
USDA Hardiness Zones: 10-11
Sun Exposure: Partial Shade to Full Sun
Water Usage Rating (at Planting): Medium
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PRESERVING POMONA
FRUITLESS OLIVE TREE
OLEA EUROPAEA ‘SWAN HILL”
Also known as the Swan Hill Olive tree, this variety of olive tree is fruitless and has little pollen. It is a moderate growing tree. The species was discovered near the town of Swan Hill in Victoria, Australia. They are drought-tolerant.
Tree Type: Evergreen
Maximum Height: 30 feet
Canopy Width: 20-25 feet
Growth Rate: 24 inches per year
Sunset Western Garden Zones: 8-9, 11-24
USDA Hardiness Zones: 8-10
Sun Exposure: Partial Shade to Full Sun
Water Usage Rating (at Planting): Low
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AUSTRALIAN WILLOW
GEIJERA PARVIFLORA
The Australian Willow has non-invasive root system, which makes them good trees for street parkways and areas with limited space. In addition, the Australian native tree is fi re resistant since its leaves are fi lled with water.
Tree Type: Evergreen
Maximum Height: 35 feet
Canopy Width: 20 feet
Growth Rate: 24-36 inches per year
Sunset Western Garden Zones: 8-9, 12-24
USDA Hardiness Zones: 9-11
Sun Exposure: Partial Shade to Full Sun
Water Usage Rating (at Planting): Medium
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PRESERVING POMONA
PURPLE-LEAF ACACIA
ACACIA BAILEYANA ‘PURPUREA’
A native of Southeastern Australia, this member of the Acacia family does have a short lifespan of approximately 30 years. It is often used as an accent tree because of its purple fl ower, but it has a dense canopy and is a good shade tree.
Tree Type: Evergreen
Maximum Height: 30 feet
Canopy Width: 20-30 feet
Growth Rate: 36-127 inches per year
Sunset Western Garden Zones: 8-9, 13-24
USDA Hardiness Zones: 8-10
Sun Exposure: Partial Shade to Full Sun
Water Usage Rating (at Planting): Very Low
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GOLDENRAIN TREE
KOELREUTERIA PANICULATA
The Goldenrain tree is native to China and can survive temperatures down to zero degrees. It was fi rst introduced to America by Thomas Jeff erson. Its yellow fl owers bloom in summer and makes a good accent tree or a shade tree.
Tree Type: Deciduous
Maximum Height: 35 feet
Canopy Width: 25-40 feet
Growth Rate: 12-24 inches per year
Sunset Western Garden Zones: 2-24
USDA Hardiness Zones: 6-9
Sun Exposure: Partial Shade to Full Sun
Water Usage Rating (at Planting): Medium
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PRESERVING POMONA
COMMON HACKBERRY / WESTERN REDBUD
CELTIS OCCIDENTALIS
Native to Eastern North America, the Hackberry can grow well in a variety of climates and is tolerant of urban conditions. The bark can be rough and appear similar to the bark of a cork tree.
Tree Type: Deciduous
Maximum Height: 80 feet
Canopy Width: 40-50 feet
Growth Rate: 24-36 inches per year
Sunset Western Garden Zones: 1-24
USDA Hardiness Zones: 2-9
Sun Exposure: Partial Shade to Full Sun
Water Usage Rating (at Planting): Medium
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HOLLYLEAF CHERRY
PRUNUS ILICIFOLIA
The Hollyleaf Cherry tree is native to Southern California. It is a drought-tolerant tree that is easy to care for.
Tree Type: Evergreen
Maximum Height: 30 feet
Canopy Width: 10-25 feet
Growth Rate: 24 inches per year
Sunset Western Garden Zones: 5-9, 12-24
USDA Hardiness Zones: 9-10
Sun Exposure: Partial Shade to Full Sun
Water Usage Rating (at Planting): Low
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PRESERVING POMONA
BRISBANE BOX
LOPHOSTEMON CONFERTUS
Another tree native to Australia, the Brisbane box is a tree that is not only drought- tolerant, but also tolerant of smog, making it ideal for urban settings.
Tree Type: Evergreen
Maximum Height: 50 feet
Canopy Width: 10-30 feet
Growth Rate: 24-36 inches per year
Sunset Western Garden Zones: 18-24
USDA Hardiness Zones: 10-11
Sun Exposure: Partial Shade to Full Sun
Water Usage Rating (at Planting): Medium
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CALIFORNIA SYCAMORE
PLATANUS RACEMOSA
The California Sycamore is found in riparian areas in California. It can tolerate extreme heat and extreme winds.
Tree Type: Evergreen
Maximum Height: 80 feet
Canopy Width: 20-50 feet
Growth Rate: 36 inches per year
Sunset Western Garden Zones: 4-24
USDA Hardiness Zones: 7-10
Sun Exposure: Partial Shade to Full Sun
Water Usage Rating (at Planting): High
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PRESERVING POMONA
COAST LIVE OAK
QUERCUS AGRIFOLIA
The Coast Live Oak is found throughout Southern California. It can tolerate extreme heat, extreme winds and drought. It will drop acorns in fall or winter.
Tree Type: Evergreen
Maximum Height: 70 feet
Canopy Width: 20-70 feet
Growth Rate: 24 inches per year
Sunset Western Garden Zones: 7-9, 14-24
USDA Hardiness Zones: 8-10
Sun Exposure: Partial Shade to Full Sun
Water Usage Rating (at Planting): Medium
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ANSI 300 TREE PRUNING STANDARDS
FORWARD
(This foreword is not part of American National Standard A300 Part 1-2001.) An industry-consensus standard must have the input of the industry that it is intended to a ff ect.
The Accredited Standards Committee A300 was approved June 28, 1991. The committee includes representatives from the residential and commercial tree care industry, the utility, municipal, and federal sectors, the landscape and nursery industries, and other interested organizations.
Representatives from varied geographic areas with broad knowledge and technical expertise contributed.
The A300 standard can be best placed in proper context if one reads its Scope, Purpose, and Application. This document presents performance standards for the care and maintenance of trees, shrubs, and other woody plants. It is intended as a guide in the drafting of maintenance specifi cations for federal, state, municipal, and private authorities including property owners, property managers, and utilities.
The A300 standard stipulates that specifi cations for tree work should be written and administered by a professional possessing the technical competence to provide for, or supervise, the management of woody landscape plants. Users of this standard must fi rst interpret its wording, then apply their knowledge of growth habits of certain plant species in a given environment. In this manner, the user ultimately develops their own specifi cations for plant maintenance.
ANSI A300 Part 1 – Pruning, should be used in conjunction with the rest of the A300 standard when writing specifi cations for tree care operations.
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PRESERVING POMONA
Suggestions for improvement of this standard should be forwarded to: NAA300 Secretary, c/o National Arborist Association, 3 Perimeter Rd. - Unit 1, Manchester, NH 03103, USA or Email:
[email protected].
This standard was processed and approved for submittal to ANSI by Accredited Standards Committee on Tree, Shrub, and Other Woody Plant Maintenance Operations – Standard Practices, A300. Committee approval of the standard does not necessarily imply that all committee members voted for its approval. At the time it approved this standard, the A300 committee had the following members:
Tim Johnson, Chair (Artistic Arborist, Inc.)
Bob Rouse, Secretary (National Arborist Association, Inc.) Organizations Represented Name of Representative
American Forests Staff (Observer)
American Nursery and Landscape Association Craig J. Regelbrugge American Society of Consulting Arborists Andrew Graham
Donald Blair (Adviser)
Beth Palys (Adviser)
American Society of Landscape Architects Ron Leighton
Asplundh Tree Expert Company Geoff Kempter
Associated Landscape Contractors of America Preston Leyshon Jeff Bourne (Alt.)
The Davey Tree Expert Company Joseph Tommasi
Dick Jones (Alt.)
Richard Rathjens (Adviser)
The F.A. Bartlett Tree Expert Company Peter Becker
Dr. Thomas Smiley (Alt.)
International Society of Arboriculture Ed Brennan
Sharon Lilly (Alt.)
National Arborist Association Ronald Rubin
Tom Mugridge (Alt.) National Park Service Robert DeFeo
Professional Grounds Management Society Kevin O’Donnell Society of Municipal Arborists Andrew Hillman
U.S. Forest Service Ed
Macie_ Mike Galvin (Alt.)
Philip D. Rodbell (Alt.)
Utility Arborist Association Jeff ery Smith
Matt Simons (Alt.)
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AMERICAN NATIONAL STANDARD FOR TREE CARE OPERATIONS –
TREE, SHRUB, AND OTHER WOODY PLANT MAINTENANCE – STANDARD PRACTICES (PRUNING)
1 ANSI A 300 STANDARDS
1.1 Scope
ANSI A300 standards present performance standards for the care and maintenance of trees, shrubs, and other woody plants.
1.2 Purpose
ANSI A300 standards are intended as guides for federal, state, municipal and private authorities including property owners, property managers, and utilities in the drafting of their maintenance specifi cations.
1.3 Application
ANSI A300 standards shall apply to any person or entity engaged in the business, trade, or performance of repairing, maintaining, or preserving trees, shrubs, or other woody plants.
1.4 Implementation
Speci fi cations for tree maintenance should be written and administered by an arborist. 2 PART 1 – PRUNING STANDARDS
2.1 Purpose
The purpose of this document is to provide standards for developing speci fi cations for tree pruning.
2.2 Reasons for pruning
The reasons for tree pruning may include, but are not limited to, reducing risk, maintaining or improving tree health and structure, improving aesthetics, or satisfying a speci fi c need.
Pruning practices for agricultural, horticultural production, or silvicultural purposes are exempt from this standard.
2.3 Safety
2.3.1 Tree maintenance shall be performed only by arborists or arborist trainees who, through related training or on-the-job experience, or both, are familiar with the practices and hazards of arboriculture and the equipment used in such operations.
2.3.2 This standard shall not take precedence over arboricultural safe work practices. 5-58
PRESERVING POMONA
2.3.3 Operations shall comply with applicable Occupational Safety and Health Administration (OSHA) standards, ANSI Z133.1, as well as state and local regulations. 3 NORMATIVE REFERENCES
The following standards contain provisions, which, through reference in the text, constitute provisions of this American National Standard. All standards are subject to revision, and parties to agreements based on this American National Standard shall apply the most recent edition of the standards indicated below.
• ANSI Z60.1, Nursery stock
• ANSI Z133.1, Tree care operations - Pruning, trimming, repairing, maintaining, and removing trees, and cutting brush - Safety requirements
• 29 CFR 1910, General industry 1)
• 29 CFR 1910.268, Telecommunications 1)
• 29 CFR 1910.269, Electric power generation, transmission, and distribution 1) • 29 CFR 1910.331 - 335, Electrical safety-related work practices 1) 4 DEFINITIONS
4.1 anvil-type pruning tool: A pruning tool that has a sharp straight blade that cuts against a fl at metal cutting surface, in contrast to a hook-and-bladetype pruning tool (4.21).
4.2 apical dominance: Inhibition of growth of lateral buds by the terminal bud.
4.3 arboriculture: The art, science, technology, and business of commercial, public, and utility tree care.
4.4 arborist: An individual engaged in the profession of arboriculture who, through experience, education, and related training, possesses the competence to provide for or supervise the management of trees and other woody plants.
4.5 arborist trainee: An individual undergoing on-the-job training to obtain the experience and the competence required to provide for or supervise the management of trees and other woody plants. Such trainees shall be under the direct supervision of an arborist.
4.6 branch bark ridge: The raised area of bark in the branch crotch that marks where the branch and parent meet.
4.7 branch collar: The swollen area at the base of a branch.
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4.8 callus: Undi ff erentiated tissue formed by the cambium around a wound.
4.9 cambium: The dividing layer of cells that forms sapwood (xylem) to the inside and inner bark (phloem) to the outside.
4.10 cleaning: Selective pruning to remove one or more of the following parts: dead, diseased, and/ or broken branches (5.6.1).
4.11 climbing spurs: Sharp, pointed devices a ffi xed to a climber’s boot used to assist in climbing trees. (syn.: gaff s, hooks, spurs, spikes, climbers)
4.12 closure: The process of woundwood covering a cut or other tree injury.
4.13 crown: The leaves and branches of a tree measured from the lowest branch on the trunk to the top of the tree.
4.14 decay: The degradation of woody tissue caused by microorganisms.
4.15 espalier: The combination of pruning, supporting, and training branches to orient a plant in one plane (5.7.2).
4.16 establishment: The point after planting when a tree’s root system has grown suffi ciently into the surrounding soil to support shoot growth and anchor the tree.
4.17 facility: A structure or equipment used to deliver or provide protection for the delivery of an essential service, such as electricity or communications.
4.18 fi nal cut: A cut that completes the removal or reduction of a branch or stub.
4.19 frond: A leaf of a palm.
4.20 heading: 1. Cutting a currently growing, or a 1-year-old shoot, back to a bud. 2. Cutting an older branch or stem back to a stub in order to meet a de fi ned structural objective. 3.
Cutting an older branch or stem back to a lateral branch not large enough to assume apical dominance in order to meet a de fi ned structural objective. Heading may or may not be an acceptable pruning practice, depending on the application.
4.21 hook-and-blade-type pruning tool: A pruning tool that has a sharp curved blade that overlaps a supporting hook; in contrast to an anvil-type pruning tool (4.1). (syn.: by-pass pruner)
4.22 interfering branches: Crossing, rubbing, or upright branches that have the potential to damage tree structure and/or health.
4.23 internodal cut: A cut located between lateral branches or buds. 5-60
PRESERVING POMONA
4.24 lateral branch: A shoot or stem growing from a parent branch or stem.
4.25 leader: A dominant or co-dominant, upright stem.
4.26 limb: A large, prominent branch.
4.27 lion’s tailing: The removal of an excessive number of inner, lateral branches from parent branches. Lion’s tailing is not an acceptable pruning practice (5.5.7).
4.28 mechanical pruning: A utility pruning technique where large-scale power equipment is used to cut back branches (5.9.2.2).
4.29 parent branch or stem: A tree trunk, limb, or prominent branch from which shoots or stems grow.
4.30 peeling: For palms: The removal of only the dead frond bases at the point they make contact with the trunk without damaging living trunk tissue. (syn.: shaving)
4.31 petiole: A stalk of a leaf or frond.
4.32 phloem: Inner bark conducting tissues that transport organic substances, primarily carbohydrates, from leaves and stems to other parts of the plant.
4.33 pollarding: The maintenance of a tree by making internodal cuts to reduce the size of a young tree, followed by the annual removal of shoot growth at its point of origin (5.7.3).
4.34 pruning: The selective removal of plant parts to meet speci fi c goals and objectives.
4.35 quali fi ed line-clearance arborist: An individual who, through related training and on- the job experience, is familiar with the equipment and hazards in line clearance and has demonstrated the ability to perform the special techniques involved. This individual may or may not be currently employed by a line clearance contractor.
4.36 quali fi ed line-clearance arborist trainee: An individual undergoing line-clearance training and who, in the course of such training, is familiar with the hazards and equipment involved in line clearance and has demonstrated ability in the performance of the special techniques involved. This individual shall be under the direct supervision of a quali fi ed line-clearance arborist.
4.37 raising: Selective pruning to provide vertical clearance (5.6.3).
4.38 reduction: Selective pruning to decrease height and/or spread (5.6.4).
4.39 remote/rural areas: Locations associated with very little human activity, land improvement, or development.
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4.40 restoration: Selective pruning to improve the structure, form, and appearance of trees that have been severely headed, vandalized, or damaged (5.7.4).
4.41 shall: As used in this standard, denotes a mandatory requirement.
4.42 should: As used in this standard, denotes an advisory recommendation.
4.43 stub: An undesirable short length of a branch remaining after a break or incorrect pruning cut is made.
4.44 thinning: Selective pruning to reduce density of live branches (5.6.2).
4.45 throwline: A small, lightweight line with a weighted end used to position a climber’s rope in a tree.
4.46 topping: The reduction of a tree’s size using heading cuts that shorten limbs or branches back to a predetermined crown limit. Topping is not an acceptable pruning practice (5.5.7).
4.47 tracing: The removal of loose, damaged tissue from in and around the wound.
4.48 urban/residential areas: Locations, such as populated areas including public and private property, that are normally associated with human activity.
4.49 utility: An entity that delivers a public service, such as electricity or communications.
4.50 utility space: The physical area occupied by a utility’s facilities and the additional space required to ensure its operation.
4.51 vista pruning: Selective pruning to allow a speci fi c view (5.7.5).
4.52 watersprouts: New stems originating from epicormic buds. (syn.: epicormics shoots)
4.53 wound: An opening that is created when the bark of a live branch or stem is penetrated, cut, or removed.
4.54 woundwood: Partially di ff erentiated tissue responsible for closing wounds. Woundwood develops from callus associated with wounds.
4.55 xylem: Wood tissue. Active xylem is sapwood; inactive xylem is heartwood.
4.56 young tree: A tree young in age or a newly transplanted tree. 5-62
PRESERVING POMONA
5 PRUNING PRACTICES
5.1 Tree inspection
5.1.1 An arborist or arborist trainee shall visually inspect each tree before beginning work.
5.1.2 If a condition is observed requiring attention beyond the original scope of the work, the condition should be reported to an immediate supervisor, the owner, or the person responsible for authorizing the work.
5.2 Tools and equipment
5.2.1 Equipment and work practices that damage living tissue and bark beyond the scope of the work should be avoided.
5.2.2 Climbing spurs shall not be used when climbing and pruning trees.
Exceptions:
-when limbs are more than throwline distance apart and there is no other means of climbing the tree;
-when the bark is thick enough to prevent damage to the cambium;
-in remote or rural utility rights-of-way.
5.3 Pruning cuts
5.3.1 Pruning tools used in making pruning cuts shall be sharp.
5.3.2 A pruning cut that removes a branch at its point of origin shall be made close to the trunk or parent limb, without cutting into the branch bark ridge or collar, or leaving a stub (see Figure 5.3.2).
5.3.3 A pruning cut that reduces the length of a branch or parent stem should bisect the angle between its branch bark ridge and an imaginary line perpendicular to the branch or stem (see Figure 5.3.3).
5.3.4 The fi nal cut shall result in a fl at surface with adjacent bark fi rmly attached.
5.3.5 When removing a dead branch, the fi nal cut shall be made just outside the collar of living tissue.
Figure 5.3.2. – A pruning cut that removes a branch at its point of origin shall be made close to the trunk or
parent limb, without cutting into the branch bark
ridge or collar, or leaving a stub. Branches too
large to support with one hand shall be precut to
avoid splitting of the wood or tearing of the bark.
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5.3.6 Tree branches shall be removed in such a manner so as not to cause damage to other parts of the tree or to other plants or property. Branches too large to support with one hand shall be precut to avoid splitting of the wood or tearing of the bark (see Figure
5.3.2). Where necessary, ropes or other equipment shall be used to lower large branches or portions of branches to the round.
5.3.7 A fi nal cut that removes a branch with a narrow angle of attachment should be made from the outside of the branch to prevent damage to the parent limb (see Figure 5.3.7).
5.3.8 Severed limbs shall be removed from the crown upon completion of the pruning, at times when the tree would be left unattended, or at the end of the workday.
5.4 Wound treatment
5.4.1 Wound treatments should not be used to cover wounds or pruning cuts, except when recommended for disease, insect, mistletoe, or sprout control, or for cosmetic reasons.
5.4.2 Wound treatments that are damaging to tree tissues shall not be used.
5.4.3 When tracing wounds, only loose, damaged tissue should be removed.
5.5 Pruning objectives
5.5.1 Pruning objectives shall be established prior to beginning any pruning operation. To obtain the de fi ned objective, the growth cycles and structure of individual species and the type of pruning to be performed should be considered.
5.5.3 Not more than 25 percent of the foliage should be removed within an annual growing season. The percentage and distribution of foliage to be removed shall be adjusted according to the plant’s species, age, health, and site.
5.5.4 Not more than 25 percent of the foliage of a branch or limb should be removed when it is cut back to a lateral. That lateral should be large enough to assume apical dominance.
5.5.5 Pruning cuts should be made in accordance with 5.3 Pruning cuts.
5.5.6 Heading should be considered an acceptable practice for shrub or specialty pruning when needed to reach a defi ned objective.
5.5.7 Topping and lion’s tailing shall be considered unacceptable pruning practices for trees.
Figure 5.3.3. – A pruning cut that reduces the length of a branch or parent stem should bisect the angle
between its branch bark ridge and an imaginary
line perpendicular to the branch or stem.
Figure 5.3.7. – A fi nal cut that removes a branch with
a narrow angle of attachment should be made
from the outside of the branch to prevent
damage to the parent limb.
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5.6 Pruning types
Speci fi cations for pruning should consist of, but are not limited to, one or more of the following types:
5.6.1 Clean: Cleaning shall consist of selective pruning to remove one or more of the following parts: dead, diseased, and/or broken branches.
5.6.1.1 Location of parts to be removed shall be speci fi ed.
5.6.1.2 Size range of parts to be removed shall be speci fi ed.
5.6.2 Thin: Thinning shall consist of selective pruning to reduce density of live branches.
5.6.2.1 Thinning should result in an even distribution of branches on individual limbs and throughout the crown.
5.6.2.2 Not more than 25 percent of the crown should be removed within an annual growing season.
5.6.2.3 Location of parts to be removed shall be speci fi ed.
5.6.2.4 Percentage of foliage and size range of parts to be removed shall be speci fi ed.
5.6.3 Raise: Raising shall consist of selective pruning to provide vertical clearance.
5.6.3.1 Vertical clearance should be speci fi ed.
5.6.3.2 Location and size range of parts to be removed should be speci fi ed.
5.6.4 Reduce: Reduction shall consist of selective pruning to decrease height and/or spread.
5.6.4.1 Consideration shall be given to the ability of a species to tolerate this type of pruning.
5.6.4.2 Location of parts to be removed and clearance should be speci fi ed.
5.6.4.3 Size range of parts should be speci fi ed.
5.7 Specialty pruning
Consideration shall be given to the ability of a species to tolerate specialty pruning, using one or more pruning types (5.6).
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5.7.1 Young trees
5.7.1.1 The reasons for young tree pruning may include, but are not limited to, reducing risk, maintaining or improving tree health and structure, improving aesthetics, or satisfying a specifi c need.
5.7.1.2 Young trees that will not tolerate repetitive pruning and have the potential to outgrow their space should be considered for relocation or removal.
5.7.1.3 At planting
5.7.1.3.1 Pruning should be limited to cleaning (5.6.1).
5.7.1.3.2 Branches should be retained on the lower trunk.
5.7.1.4 Once established
5.7.1.4.1 Cleaning should be performed (5.6.1).
5.7.1.4.2 Rubbing and poorly attached branches should be removed.
5.7.1.4.3 A central leader or leader(s) as appropriate should be developed.
5.7.1.4.4 A strong, properly spaced scaff old branch structure should be selected and maintained.
5.7.1.4.5 Interfering branches should be reduced or removed.
5.7.2 Espalier
5.7.2.1 Branches that extend outside the desired plane of growth shall be pruned or tied back.
5.7.2.2 Ties should be replaced as needed to prevent girdling the branches at the attachment site.
5.7.3 Pollarding
5.7.3.1 Consideration shall be given to the ability of the individual tree to respond to pollarding.
5.7.3.2 Management plans shall be made prior to the start of the pollarding process for routine removal of watersprouts.
5.7.3.3 Internodal cuts shall be made at speci fi c locations to start the pollarding process. After the initial cuts are made, no additional internodal cut shall be made. 5-66
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5.7.3.4 Watersprouts growing from the cut ends of branches (knuckles) should be removed annually during the dormant season.
5.7.4 Restoration
5.7.4.1 Restoration shall consist of selective pruning to improve the structure, form, and appearance of trees that have been severely headed, vandalized, or damaged.
5.7.4.2 Location in tree, size range of parts, and percentage of watersprouts to be removed should be specifi ed.
5.7.5 Vista pruning
5.7.5.1 Vista pruning shall consist of selective pruning to allow a speci fi c view.
5.7.5.2 Size range of parts, location in tree, and percentage of foliage to be removed should be specifi ed.
5.8 Palm pruning
5.8.1 Palm pruning should be performed when fronds, fruit, or loose petioles may create a dangerous condition.
5.8.2 Live healthy fronds, initiating at an angle of 45 degrees or greater from horizontal, with frond tips at or below horizontal, should not be removed.
5.8.3 Fronds removed should be severed close to the petiole base without damaging living trunk tissue.
5.8.4 Palm peeling (shaving) should consist of the removal of only the dead frond bases at the point they make contact with the trunk without damaging living trunk tissue.
5.9 Utility pruning
5.9.1 General
5.9.1.1 The purpose of utility pruning is to prevent the loss of service, comply with mandated clearance laws, prevent damage to equipment, avoid access impairment, and uphold the intended usage of the facility/utility space.
5.9.1.2 Only a quali fi ed line clearance arborist or line clearance arborist trainee shall be assigned to line clearance work in accordance with ANSI Z133.1, 29 CFR 1910.331 – 335, 29 CFR 1910.268 or 29 CFR 910.269.
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5.9.1.3 Utility pruning operations are exempt from requirements in 5.1 Tree Inspection:
5.1.1 An arborist or arborist trainee shall visually inspect each tree before beginning work.
5.1.2 If a condition is observed requiring attention beyond the original scope of the work, the condition should be reported to an immediate supervisor, the owner, or the person responsible for authorizing the work.
5.9.1.4 Safety inspections of the work area are required as outlined in ANSI Z133.1 4.1.3, job briefi ng.
5.9.2 Utility crown reduction pruning
5.9.2.1 Urban/residential environment
5.9.2.1.1 Pruning cuts should be made in accordance with 5.3, Pruning cuts. The following requirements and recommendations of 5.9.2.1.1 are repeated from 5.3 Pruning cuts.
5.9.2.1.1.1 A pruning cut that removes a branch at its point of origin shall be made close to the trunk or parent limb, without cutting into the branch bark ridge or collar, or leaving a stub (see Figure 5.3.2).
5.9.2.1.1.2 A pruning cut that reduces the length of a branch or parent stem should bisect the angle between its branch bark ridge and an imaginary line perpendicular to the branch or stem (see Figure 5.3.3).
5.9.2.1.1.3 The fi nal cut shall result in a fl at surface with adjacent bark fi rmly attached.
5.9.2.1.1.4 When removing a dead branch, the fi nal cut shall be made just outside the collar of living tissue.
5.9.2.1.1.5 Tree branches shall be removed in such a manner so as not to cause damage to other parts of the tree or to other plants or property. Branches too large to support with one hand shall be precut to avoid splitting of the wood or tearing of the bark (see Figure
5.3.2). Where necessary, ropes or other equipment shall be used to lower large branches or portions of branches to the ground.
5.9.2.1.1.6 A fi nal cut that removes a branch with a narrow angle of attachment should be made from the bottom of the branch to prevent damage to the parent limb (see Figure 5.3.7).
5.9.2.1.2 A minimum number of pruning cuts should be made to accomplish the purpose of facility/utility pruning. The natural structure of the tree should be considered. 5-68
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5.9.2.1.3 Trees directly under and growing into facility/utility spaces should be removed or pruned.
Such pruning should be done by removing entire branches or by removing branches that have laterals growing into (or once pruned, will grow into) the facility/utility space.
5.9.2.1.4 Trees growing next to, and into or toward facility/utility spaces should be pruned by reducing branches to laterals (5.3.3) to direct growth away from the utility space or by removing entire branches. Branches that, when cut, will produce watersprouts that would grow into facilities and/or utility space should be removed.
5.9.2.1.5 Branches should be cut to laterals or the parent branch and not at a pre-established clearing limit. If clearance limits are established, pruning cuts should be made at laterals or parent branches outside the specifi ed clearance zone.
5.9.2.2 Rural/remote locations – mechanical pruning Cuts should be made close to the main stem, outside of the branch bark ridge and branch collar. Precautions should be taken to avoid stripping or tearing of bark or excessive wounding.
5.9.3 Emergency service restoration
During a utility-declared emergency, service must be restored as quickly as possible in accordance with ANSI Z133.1, 29 CFR 1910.331 – 335, 29 CFR 1910.268, or 29 CFR 1910.269. At such times it may be necessary, because of safety and the urgency of service restoration, to deviate from the use of proper pruning techniques as de fi ned in this standard. Following the emergency, corrective pruning should be done as necessary.
REFERENCE PUBLICATIONS
International Society of Arboriculture (ISA). 1995. Tree Pruning Guidelines. Savoy, IL: International Society of Arboriculture (ISA).
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GENERAL LANDSCAPING AND WATER CONSERVATION
In addition to the requirements for Fences and Trees, this section of the guidelines is also intended to provide guidance and resources for general landscaping issues that occur in Pomona’s Historic Districts.
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USDA HARDINESS ZONE
The United States Department of Agriculture created hardiness zones to show how well plants will do in diff erent areas of the country. The drawback is that the zones are based on minimum winter temperatures. This can lead to vastly diff erent climates falling into the same zone. While useful, the Sunset Climate zones are a more accurate representation of the varied climates in the western United States.
SUNSET CLIMATE ZONES
Sunset’s Western Garden Book has been a respected source for plant and landscape information for over 80 years. Sunset breaks down the west into 24 climate zones. IT takes into account summer and winter temperatures, terrain, and air infl uences, among other things. These climates zones are more specifi c than the USDA Hardiness zones. Pomona is in Zone 18. Parts of Claremont, Upland and other foothill communities are located in Zone 19. The diff erence between the zones is mostly elevation so some Zone 19 plants may also do well in Pomona even though they are not listed for Zone 18.
CALIFORNIA NATIVE PLANTS
Planting your yard with California native plants has two benefi ts. First, they are more historically appropriate since historically native plants were commonly used because they were readily available. Second, they will lower your water costs since they tend to be drought-tolerant and can withstand the hot summers and the high winds. There are numerous sources for California native plants. The Metropolitan Water District’s Be Water Wise website has information on California native plants and general landscaping information. The website is at https://www.bewaterwise. com/california-native-plants.html
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DROUGHT TOLERANT PLANTS
Drought tolerant plants are an easy way to reduce your water usage. They usually require less, if any water, once they are established, and can usually tolerate the heat and winds that Pomona gets.
There are several resources nearby to assist you in choosing appropriate plants.
The California Botanic Garden in Claremont has gardens, classes, and even a nursey where you can purchase native and drought tolerant plants. For more information go to their website at https:// www.calbg.org/.
The Los Angeles County Arboretum and Botanic Garden is located in Arcadia. They also have classes in addition to the various gardens on site. For more information go to their website at https://www.arboretum.org/.
The Riverside – Corona Resource Conservation District has developed native gardens that include Citrus varieties among other fruit species that will grow in the area. They have partnered with the University of California Riverside to o ff er classes and information on native and drought tolerant plants. For more information go to their website at https://www.rcrcd.org/
IRRIGATION SYSTEMS
Regular sprinkler systems can be very wasteful of water. They can over spray onto sidewalks and walkways and lead to a great deal of evaporation. Drip systems use smaller heads that reduce the amount of over spray and the focused location provide more water to plants and shrubs.
Existing sprinkler systems can be modi fi ed to install drip systems for planting beds. To improve your sprinkler systems and conserve water, you can do the following:
Water at night, it will less water to evaporate.
Fix and adjust sprinkler heads to reduce overspray.
Retrofi t sprinkler systems to drip irrigation for planting beds.
These steps are relatively inexpensive. Replacement sprinkler heads are just a few dollars each.
Entire Drip Irrigation conversion kits are under $100.00.
SMART IRRIGATION CONTROLLERS
Smart Controllers are irrigation timers that connect to the internet to monitor and adjust watering schedules based on the weather. Rachio, Orbit, Rainbird, and other companies sell smart irrigation controllers. A smart irrigation controller can save you 20-30% on your water bill. Check to see if a rebate is available to help you cover the cost of a controller. 5-72
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LAWN ALTERNATIVES
DESIGN STANDARDS FOR REPLACING LAWNS
• Arti fi cial Turf is prohibited
Artifi cial turf for historic districts is not appropriate. It does not improve the urban heat island eff ect and hurts existing yard and street trees as yards are no longer watered. Several alternatives are drought-tolerant and require little maintenance.
COMMON YARROW
ACHILLEA MILLEFOLIUM
For a lawn look, mow once a month, for a meadow look, mow 2 times per year. Not good for high foot traffi c areas. Will develop a fl ower.
DUNE SEDGE
CAREX PANSA
Only need to water twice a month. Will get 8-12” in height. To keep a lawn look, trim with a string trimmer 2-3 times per year.
CLUSTERED FIELD SAGE
CAREX PRAEGRACILIS
Drought tolerant and good for high foot traffi c, mow to keep a lawn look.
CITY OF POMONA
505 South Garey Avenue
Pomona, CA 91766
(909) 620-2311
www.pomonaca.gov