SR-07-22-2014-3C - 913-002City Council Meeting: July 22, 2014
Agenda Item: °C-
To: Mayor and City Council
From: Martin Pastucha, Director of Public Works
Subject: Colorado Esplanade Tree Selection
Recommended Action
Staff recommends that the City Council:
1. Approve the Mexican sycamore (Platanus mexicana) as the framing tree to be
used along Colorado Avenue for the Colorado Esplanade project.
2. Approve the California sycamore (Platanus racemosa) as an alternative framing
tree to be used along Colorado Avenue for the Colorado Esplanade project in
case there are availability and cost issues with the Platanus mexicana.
Executive Summary
The Colorado Esplanade Project is a circulation infrastructure and streetscape project
located between the future terminus of the regional Expo light rail line, Downtown, and
the Santa Monica Pier. A component of this project consists of lining Colorado Avenue
both on the north and south sides with a "framing tree" spaced every 25 feet.
On Mav 14, 2013 Council approved this project along with three potential tree species
(ranked 1 to 3) to be used as the framing tree. For various reasons discussed below,
these trees are no longer a viable option. The Public Works Department, Planning and
Community Development Department, the Urban Forest Task Force (UFTF), the UFTF
Species Subcommittee, and the project landscape architect worked together to
research and propose viable alternatives. Ultimately, the Urban Forest Task Force, the
UFTF Species Subcommittee and the Public Works Department arrived at the Platanus
mexicana as the first choice tree and the Platanus racemosa as the alternate second
choice tree.
Background
On May 14 2013, Council approved the final design for the full Colorado Esplanade and
directed staff to prepare a bid package and to solicit bids for the reduced footprint core
project, a smaller portion of the Colorado Esplanade design to be bid for construction.
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A display of the footprint core project is shown in the above referenced May 14, 2013
Council report. An important part of this approved design was the use of a framing tree
along the north and south sides of Colorado Avenue that creates a uniform view corridor
and frames the view of the Pier Sign. The tree approved for this project was the
Queensland kauri (Agathis robusta) with the two alternatives being the Canary island
pine ( Pinus canariensis) and the spotted gum (Corymbia maculate).
Discussion
Since the approval of the final design of the Colorado Esplanade, staff began preparing
construction documents and continued examining the tree options.
Agathis robusta
In an effort to reduce costs, staff looked into purchasing the Agathis robusta at a smaller
size and allowing it to grow in boxes until construction of the Colorado Esplanade
began. Staff was unable to find a sufficient number of Agathis robusta to fill the
Colorado Avenue planting needs. Further research revealed that there was not a
sufficient supply of this tree species available anywhere within a reasonable shipping
distance. The trees would likely have to be shipped in from Australia. This option could
not be accommodated within the project budget.
Pinus canariensis
The Pinus canariensis was available but further research into this tree species led the
UFTF Species Subcommittee to conclude that it is not a good fit for this project. The
tree creates heavy pine cones that frequently drop causing a safety hazard. In addition,
the large volume of needle drop on a pedestrian plaza would have been problematic.
Maintenance of the trees to eliminate the hazard of the pine cones would be too
extensive and costly for it to remain a viable option.
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Corymbia maculate
The Corymbia maculate also has a potential safety issue similar to the Pinus
canariensis. The limbs have a tendency to fall, creating a safety hazard while making
maintenance challenging and costly.
Staff with Public Works, Planning and Community Development, the Urban Forest Task
Force (UFTF), the UFTF Species Subcommittee, and the project landscape architect
proposed new framing tree alternatives to fit the needs of this project. Numerous
species were considered and discussed at length, including: Corymbia citriodora,
Eucalyptus deglupta, Eucalyptus nicholii, Hymenosporum flavum, Liquidamber
styraciflua, Magnolia grandiflora 'D.D. Blancard', Metasequoia glyptostroboides, Pinus
radiata, Sequoia sempenrirens, Taxodium distichum, among others. Selection criteria
included:
1. Compliant with the guiding principles, goals and strategies of the Urban Forest
Master Plan
2. Native to region
3. Available from tree nurseries in California or adjacent states in appropriate size
4. Relatively drought tolerant once established
5. Highly suited to the environment
6. Flexible to pruning
7. Ability to deliver high levels of environmental benefits and urban tree canopy
8. Ability to grow well in structural soil
9. Low risk of failure if managed appropriately
10. Uniform growth amongst local population to produce high aesthetic value
11. Seasonal aesthetics
Upon recommendation from the UFTF Species Subcommittee and the City's Urban
Forester, on June 4, 2014, the Urban Forest Task Force approved the Mexican
sycamore (Platanus mexicana) as the framing tree to be used along Colorado Avenue
for the Colorado Esplanade project. The California sycamore (Platanus racemosa) was
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approved as an alternate. Mexican sycamore was favored over California sycamore as
it tends to have a more upright growth habit.
Platanus mexicana
Financial Impacts & Budget Actions
Platanus racemosa
There is no immediate financial impact or budget action necessary as a result of the
recommended action. The tree cost remains within the estimated budget approved for
this project.
Prepared by: Zach Pollard, Civil Engineer
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Forwarded to Council:
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Rod Gould
City Manager