CITY COUNCIL WINN ROOM SUBCOMMITTEE STAFF REPORT
May 16, 2024 {{section.number}}a
WINN ROOM REMODEL AND LIBRARY PARK TREES
RECOMMENDATION:
Receive a report on trees potentially affected by the Winn Room Remodel concepts and analysis of options for replacement and transplant.
BACKGROUND:
At the City Council’s December 12, 2023 discussion of Winn Room remodel options, the Council requested additional information regarding the impact to nearby trees for each of the conceptual design options. The Winn Room Subcommittee requested information regarding options to replace or transplant any displaced trees, including costs.
ANALYSIS:
Of the four Winn Room remodel options, two were found to directly impact City trees to the point of extensive root mitigation and/or the need to completely remove the trees.
Trees must be given ample space for their canopies to spread and root system to absorb water.
The threshold for root mitigation, according to International Society of Arboriculture, is six times the diameter of the tree trunk. Staff researched replacement and transplant options for trees affected by the two Winn Room concepts.
Option Three, the “Internal Expansion” would require the removal and or transplant of one tree:
Tree 5, a Canary Island Pine. Removal or transplant would be necessary because this concept expands the Winn room to fill the existing gap between the two buildings in which the Pine resides.
Option Four, the “Larger Expansion” would require the removal and or transplant of five trees: an Evergreen Coral, two New Zealand Christmas, a Canary Island Pine, and a Cajeput/Melaleuca tree. The proximity of the expansion would directly impact the nearby trees’ root system and encroach on their canopies.
All impacted trees were evaluated in August of 2021 and were rated as low risk and in fair to good health. The lean on Tree 4, the Cajeput/Melaleuca, does not make it an ideal transplant candidate and would be best to get replaced or substituted with a species from the Approved Street Tree List. Replacement would also be a better option for Tree 1, the Evergreen Coral, that has a history of losing branches.
Transplanting trees are only guaranteed at the first stage by the contractor, but the long-term survivability of the transplanted tree is based on ongoing maintenance by City staff. Maintenance and care encompass hand watering, providing nutrients, checking the guying system for stability, inspection for disease, monitoring during rain and heavy winds, Arborist evaluations for progress, and pest management. The prices in the Fiscal Impact section below are only to relocate the trees within proximate City property, which would include the Library and Spreckels Center property. Extra costs would incur if trees were to get transported to a different location. There are three vacant sites in front of the Spreckels Center, which can accommodate the transplanted trees. The remaining two trees would need a different location outside of the existing property to accommodate the large sized tree box.
Replacement of the five impacted trees would come in the size of a thirty-six inch to forty-eightinch box trees handpicked by City staff for quality and structural integrity. Replacements would be planted in three vacant tree sites in front of Spreckels Center near Orange Ave and or at a City park where new trees could be given ample canopy space. The remaining two trees would need to be relocated to a different site and/or planted in the parkway on Sixth St and D Ave.
FISCAL IMPACT:
The replacement and transplant costs for each tree are detailed in the following table.
ESTIMATED REPLACEMENT COSTS (48 inch box)
Tree 1 – Evergreen Coral $19,500
Tree 2 - New Zealand Christmas $16,000
Tree 3 – New Zealand Christmas $16,000
Tree 4 – Cajeput / Melaleuca $12,500
Tree 5 – Canary Island Pine $16,000
Irrigation and Sod repairs $500
Total Estimated Replacement Cost $80,500
ESTIMATED TRANSPLANT COST
Tree 1 – Evergreen Coral $30,000
Tree 2 – New Zealand Christmas $17,000
Tree 3 – New Zealand Christmas $20,000
Tree 4 – Cajeput / Melaleuca $6,500
Tree 5 – Canary Island Pine $30,000
Maintenance and Care Cost (4 years) $47,000
Irrigation and Sod repairs $1,200
Total Estimated Transplant and Maintenance Cost $151,700 Remodel Option 4, the Larger Expansion, would cost $80,500 to $151,700 to replace or transplant the five affected trees including maintenance, care, irrigation, and sod repair costs.
Remodel Option 3, the Internal Expansion, would cost $16,000 to $30,000 to replace or transplant one affected tree, plus approximately $500 to $9,640 in maintenance, care, irrigation and sod repair costs.
ALTERNATIVE:
The Council may request additional research.
CALIFORNIA ENVIRONMENTAL QUALITY ACT:
Not Applicable
PUBLIC NOTICE:
No notice required.
ATTACHMENTS:
1. Concepts 3 “Internal Expansion” and 4 “Larger Expansion” Design and Park Overlays Submitted By: Public Services and Engineering Department / Arturo Valdivia