TR-2022-002_Arborist Peer Review t~ West Coast Arborists Inc.
u e ot� 781 San Pablo Ave
7
, IPinole,CA 95050
Di (510)921-3925
cuPERri OVED Wcainc.com
Case# I R-2022-002
Application Number(s)
Approva I B�eo-P fiYJAo2r0AafF
Approva I Dp are2ff3r?j?kv of Cuoertino
Signature BriarrmrkawkMa
City of Cup&Mhbnager
10300 Torre Avenue
Cupertino, CA 95014-3202
Re: Arborist Peer Review 11112 Firethorn Drive
Scope of Work:
The City of Cupertino has contracted West Coast Arborists Inc. (WCA) for arborist services. In
January 2022, the City of San Carlos requested a review of an arborist report from December
2021, verify the removal of the tree, clarify if the proposed replacement trees and their
locations are adequate, and review the proposed irrigation method. The City provided an
arborist report by ISA Certified Arborist Kevin Allen of Commercial Tree Care, complete with
photographs and descriptions of the tree's presumed hardscape damage. I visited the site on
January 18, 2022, summarizing my observations herein. This letter is not an official risk
assessment, and my findings are limited to the information provided to me by City staff, as well
as visual observations from the ground level.
Satellite Imagery:
White circle
indicates the
ubject tree's
location.
West Coast Arborists Inc.—Arborist Peer Review: City of Cupertino—February 11, 2022
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Community UevelopmenPrDTeparfineBnPan Pablo Ave Pinole,CA 94564-(510)921-3925 Wcainc.com
&ig?q�% ivision — Cupertino
CUPERTINO APPROVED
Case# TR-20 -00
APP
Approval Body: Dir
Approva I Date
Signature
T't
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— S
The above image shows the subject tree in fair health and fair condition.The canopy's relatively
balanced structure was leaning slightly over the roadway. The foliage was healthy, green, and
standard for the species. I did not observe direct signs or any symptoms of a pest (such as a
borer insect) or pathogen (such as fungi or oomycetes) infestation. Despite its fair condition,
the species did not appear appropriate for the limited growing space at 11112 Firethorn Drive.
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e
The above photo on the left shows a covered crack (white oval); this was an exposed crack in
the Arborist Report from December. The tree likely caused the damage, considering the tree's
size and the wall's proximity to the trunk.
The above photo on the right shows flags, presumably for underground utility work. These flags
are well within the tree's critical root zone, and excavation work would negatively impact the
tree. Depending on how extensive the excavation is, a severe impact on the tree is possible.
West Coast Arborists Inc.—Arborist Peer Review: City of Cupertino—February 11, 2022
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Community evCoast A bt rl�epa c. —781 San Pablo Ave Pinole,CA 94564-(510) 921-3925 Wcainc.com
RKMNOSEPWLi�1t4on-- Cupertino
CUPERTINO The speciesAP OLVr 6)for its area, particularly the root zone, where it does not have
Case # sign ificalff22QWQw radially and anchor itself. Many hardwood trees, such as the subject
tree, h&)oaiirctatr4Votjaqis that extend far past the tree's crown to provide anchorage and search
for nutrients water; the subject tree does not have this ability around its circumference. This
Approva l B d r to t
I°acVOpp �aci tSb w radially is due to a nearby wall one foot from the tree's trunk. The tree
Approval Dpt?,,,,�/42h7/rs pa Anm,4ap 41rp@d;, and is likely to develop significantly more; it will likely
Signature cau5gianoeEHh6mLs9Jxme damage in the years to come (likely in a repeated fashion to the wall).
Additionall�;1fildapmposed underground utility work would impact the tree within its Critical
Root Zone, thus causing significant (and potentially severe) damage to tree stability.
Additionally, the tree is considered protected as it is a "Development Tree" under the City of
Cupertino, California Municipal Code. Due to the culmination of all factors, I verify removal as
justifiable.
Irrigation Plans Review:
The December report listed pop-up sprinklers for the proposed irrigation. Pop-up sprinklers are
not ideal for trees as they can directly splash tree trunks, increasing susceptibility to various
root rot pathogens (mainly fungal pathogens). However, landscape trees often experience pop-
up sprinklers as their primary source of moisture without developing root rot. I believe a drip-
irrigation system is preferable, though pop-up sprinklers are sufficient.
Replacement Trees and Locations Review:
The December report proposed two Podocarpus macrophyllus to replace the current
Podocarpus gracilior. P. macrophyllus generally has a less invasive root system than the
larger P. gracilior and is less likely to cause hardscape damage. I believe P. macrophyllus is a
more viable option than the current P. gracilior given the proximity to sidewalks; both site
locations listed for planting are conceivable as well. However, two newly planted P.
macrophyllus's likely would not replace the ecosystem services (such as air and water filtration
and wildlife habitat) of the mature P. gracilior for decades. If feasible, I recommend planting at
least one additional P. macrophyllus at 11112 Firethorn Drive; this may be difficult given space
restrictions.
Conclusion:
The subject tree is in a poor location, considering the aggressive growing potential of the
species, its proximity to the nearby HOA wall, and the proposed utility wires within the critical
root zone. With these factors in mind, despite the fact it is a "Development Tree" according to
the City of Cupertino, California Municipal Code, I believe tree removal is justified.
The replacement tree species, Podocarpus macrophyllus, is a viable replacement option. It is
feasible given its less aggressive root and trunk growth than Podocarpus gracilior. It does not
cause significant hardscape damage despite being frequently planted as a sidewalk tree in the
Bay Area.
West Coast Arborists Inc.—Arborist Peer Review: City of Cupertino—February 11, 2022
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Community Uevelopmenf rd'eparfineBnPan Pablo Ave Pinole,CA 94564-(510)921-3925 Wcainc.com
Planning Division — Cupertino
CUPERTINO Thank you fcAf1P(R&V Me to assist you in your tree assessment needs.
Case# TR-2022-002
Sinceree4yplication Number(s)
Approva I Bogly rDirec or/Staff
Approva I Date _ 04/27/22
Plant neaizh-Care Aroor15z: Peter Richards
Signature CUtip aQ Harkousha
Case Manager
ISA Certified Arborist- Credential ID: WE-13340
ISA Tree Risk Assessment Qualification- Credential ID: 31985411
Qualified Applicator License- Credential ID: 161
Glossary:
Rating Category Health Structure Form
Fair Reduced vigor. A single defect of a Major
Damage due to insects significant nature or asymmetries/deviations
or diseases may be multiple moderate from species norm
significant and defects. Defects are and/or intended use.
associated with not practical to correct Function and/or
defoliation but is not or would require aesthetics are
likely to be fatal.Twig multiple treatments compromised.
dieback, defoliation, over several years.
discoloration, and/or
dead branches may
comprise up to 50%of
the crown.
Poor Unhealthy and A single serious defect Largely
declining in or multiple significant asymmetric/abnormal.
appearance. Poor defects. Recent change Detracts from intended
vigor. Low foliage in tree orientation. use and/or aesthetics
density and poor Observed structural to a significant degree.
foliage color are problems cannot be
present. Potentially corrected. Failure may
fatal pest infestation. occur at any time.
Extensive twig and/or
branch dieback.
Bibliography:
Council of Tree & Landscape Appraisers. Guide for Plant Appraisal, 10t"Edition:Second Printing.
International Society of Arboriculture.June 2019. Print.
West Coast Arborists Inc.—Arborist Peer Review: City of Cupertino—February 11, 2022
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Community UevelopmenPrLTeparfineBnPan Pablo Ave Pinole,CA 94564-(510)921-3925 Wcainc.com
Planning Division — CupertlnoASSUMPTIONSAND LIMITING CONDITIONS
CUPERTINO 1. CareAWROgftn to obtain all information from reliable sources.All data has been verified insofar as
i �,v,� the Consultant can neither guarantee nor be responsible for the accuracy of
Case# ;w1a , ,, 12V—M ed by othorc St2pdard of Care has been met with regards to this project within
IiBlM919019` Mrmal conditions.
Approva I BodyZ Dif Nk/uf ,Pk ill not be required to give testimony or to attend court by reason of this report unless
Approva I Date PNs?e414t contractual agreements are made,including payment of an additional fee for such services as
Signature Brianngc��e instlia�fee schedule and contract of engagement.
Case Manager
3. Loss or alteration of any part of this report invalidates the entire report.
4. Possession of this report or a copy thereof does not imply right of publication or use for any purpose by
any other than the person to whom it is addressed,without the prior written consent of the Consultant.
5. This report and any values expressed herein represent the opinion of the Consultant,and the Consultant's
fee is in no way contingent upon the reporting of a stipulated result,a specified value,the occurrence of a
subsequent event, nor upon any finding to be reported.
6. Unless expressed otherwise: 1) information contained in this report covers only those items that were
examined and reflects the condition of those items at the time of inspection;and 2)the inspection is
limited to visual examination of accessible items without dissection,excavation,or coring, unless
otherwise stated.There is no warranty or guarantee,expressed or implied,that problems or deficiencies
of the tree(s)or property in question may not arise in the future.
7. Arborists are tree specialists who use their education, knowledge,training, and experience to examine
trees, recommend measures to enhance the beauty and health of trees,and attempt to reduce the risk of
living near trees. It is highly recommended that you follow the arborist recommendations; however,you
may choose to accept or disregard the recommendations and/or seek additional advice.
8. Arborists cannot detect every condition that could possible lead to the structural failure of a tree.Trees
are living organisms that fail in ways we do not fully understand. Conditions are often hidden within trees
and below ground.Arborists cannot guarantee that a tree will be healthy or safe under all circumstances,
or for a specific period of time.
9. Any recommendation and/or performed treatments(including, but not limited to, pruning or removal)of
trees may involve considerations beyond the scope of the arborist's services,such as property
boundaries, property ownership,site lines,disputes between neighbors,and any other related issues.
Arborists cannot take such considerations into account unless complete and accurate information is
disclosed to the arborist.An arborist can then be expected to consider and reasonably rely on the
completeness and accuracy of the information provided.
10. The author has no personal interest or bias with respect to the subject matter of this report or the parties
involved. He/she has inspected the subject tree(s) and to the best of their knowledge and belief,all
statements and information presented in the report are true and correct.
West Coast Arborists Inc.—Arborist Peer Review: City of Cupertino—February 11, 2022
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