Arborist Peer Review C1 Report October 6, 2022
Danielle Condit
City of Cupertino H0RT JCIENCE
10300 Torre Avenue enftTtrTr C4MSk1t71NG
Cupertino CA, 95014
Subject: Tree Removal Report Peer Review
The Hamptons Parking Lot Expansion
19500 Pruneridge Ave., Cupertino, CA 95014
Dear Ms. Condit:
The City of Cupertino requested that HortScience I Bartlett Consulting, Divisions of The F. A.
Bartlett Tree Expert Company, provide a peer review of the Arborist Report prepared by
HortScience I Bartlett Consulting (dated July 2022) and Architecture and Site Approval Plans
prepared by IMA dated September 17, 2022. The report reviews the applicant's request to
remove and replace 11 trees due to a new parking lot. You asked that we provide
professional opinions to verify:
1. Please verify if removal is recommended and assess the trees proposed to be
removed. Are they dead and should be removed with this permit? Is removal justified,
please explain why or why not.
2. Please verify if the replacement plan is acceptable/supported per your expertise of
tree replacements, to ensure that the trees being removed are adequately replaced.
3. Please verify if the replacement plan includes trees planted at grade level and that
the trees being replaced are located near or at similar locations as the ones removed.
4. Please verify that the timing for replacements would be sufficient and would ensure a
healthy tree will be grown. Please recommend specific timing for replacements.
5. Please assess existing trees that are to remain and any new demolition and/or
hardscape proposed within the tree protection zone (TPZ). Assess if the applicants'
arborists need to amend their arborist report to address any impacts to the TPZ of
any existing trees that are to remain effected by the project scope—and (if needed)
include mitigated measures to impacted tree(s) if impact exceeds best practices to
the TPZ and tress health and longevity (25% impact to TPZ).
6. Please conduct a site visit to support analysis and findings. I will coordinate with the
applicant to go on-site.
The following summarizes my observations and assessment. I visited the site on September
27, 2022, and preformed a visual inspection from the ground.
1. Please verify if removal is recommended and assess the trees proposed to be
removed. Are they dead and should be removed with this permit? Is removal justified,
please explain why or why not.
Based on the footprint and impacts of the parking lot development and the condition and
suitability of the existing trees, all 11 trees are within 10' of the construction limits. Redwoods
#181, 183 and 184 are within the proposed driveway alignment and cannot be preserved in
the current design. The London plane trees are located between the curbing and will have
major root zone compaction and loss of pervious area needed to provide soil moisture. The
long-term outcome would be beyond the construction tolerance for these trees.
2. Please verify if the replacement plan is acceptable/supported per your expertise of
tree replacements, to ensure that the trees being removed are adequately replaced.
HortScience I Bartlett Consulting . Divisions of The F.A. Bartlett Tree Expert Company
2550 gch Street,Suite#112, Berkeley CA . 925.484.0211 . www.hortscience.com
Tree Removal Permit Peer Review
City of Cupertino— 19500 Pruneridge Ave., Cupertino, CA Page 2
The replacement plan provides a 1:1 replacement for the 11 trees to be removed. Brisbane
box has a similar height and spread as London plane. Coast redwoods require adequate
supplemental irrigation to survive in Cupertino. I recommend substituting the coast redwoods
with another species more suitable for the south bay climate. The replacements proposed are
all 36" boxes and comply with the replacement requirement based on the City of Cupertino's
Tree Protection ordinance 14.18.180 in (Table 1).
3. Verify if the replacement plan includes trees planted at grade level and that the trees
being replaced are located near or at similar locations as the ones removed.
Planting Schedule L - 800 and Planting Plans L -801 and 802 do not provide either planting
grade or staking specifications. Schematics taken from The Urban Tree Foundation are
Diameter of Trunk Size of Removed Tree Replacement Trees
(Measured 4'/2 feet above grade)
Up to 12 inches* One 24" box tree
Over 12 inches and up to 18 inches Two 24" box trees or One 36" box tree
Over 18 inches and up to 36 inches
Over 36 inches One 36" box tree
Heritage tree One 48" box tree
* Does not apply to R1,Al,A, RHS, and R2 zones except required privacy plantings trees in R1
zones
Table 1. Replacement schedule size class requirements.
provided to ensure proper planting depth and staking occur(Figure 1 and 2, next page).
Eight replacement trees would be installed near the location of the trees to be removed.
Three replacement trees, as plotted on Planting Plan L-801, would be located in the northern
side of the parking lot. The planting of two additional redwoods and a Brisbane box in the
northeast corner will provide limited space for mature height and spread. I recommend the
relocation of the two redwoods to another suitable location on the property. One redwood
also is proposed on top of the utility easement. The Brisbane box could be planted at 20'from
the existing coast redwood #197. One of the proposed redwoods is also located on top of the
Public Utility Easement and could be an issue if excavation is ever required within the
easement.
HortScience I Bartlett Consulting . Divisions of The F.A. Bartlett Tree Expert Company
2550 9`h Street,Suite#112, Berkeley CA . 925.484.0211 . www.hortscience.com
Tree Removal Permit Peer Review
City of Cupertino— 19500 Pruneridge Ave., Cupertino, CA Page 3
Central leader.(See aawn
observations detail)_
Top of mot ball shall be Hush wd h
finished grade.
i
Trunk caliper shall Priam,mobbing,Ighty tamp sdl
meet ANSI Z6g current nwM the rant ball in 6 tills W
edition for ma ball sloe_ bran'lree i not aver compact
When We Alai li has been
Root ball modified as backfilled,i water around the
required. root bell W settle We sal_
Loa;ened sail_Dig and Wm We
soil W reduce m pacfim to the
Round-ropped area and depth shown.
sell bens 4 high x 8"wide
above root ball surf.— 4"lay. mukh.
shallI cansWxted around No more Bran t"al mulch on
the root ball.E1 n shall / tap of root ball.(S—
i at root ball pedphery. / specifirafims for mukh}_
Finished grade_
Existing soil. :•�S,
Slope sides of laysenq -. C ..•. r. Notes'
T -'. d R;`'f.'.•.•. 1-Trees shall be guahly
prescribed in rrawn
Bettnm of rod hall rests on ohservatiore and rod
exislirg or remmpacted observatiers details and
sal. I specTicalions
f' 3,widest dimension o(roat ball.
r SECTIONVIEW 2-See specihcations(or
Width requnemenW related W
TREE wl BERM (EXISTING SOIL NOT MODIFIED) hisddaL
Figure1. Tree planting schematic showing planting at grade with root flair
visible at ground level.
Remove nursery stake_If
centralleader needstt be
Rubbertree ties. straightened or held eni 9Is
eceplable to allach a Y"x 8'
bamboo pale to the central leader
stkes. and trunk.
Prevailing
w rd.
k� 32•long non-abrasive rui has.
PLAN VIEW r� { Two(2)three inch lodge ipine
stakes.Install approximately 2"
�n away ban[he edge of the mot
I' ball.Slake location shall not
interfere with pemanent branches.
b
SECTION VIEW
TREE STAKING-LODGE POLES (2)
Figure 2. Tree staking using wood poles; metal T posts may be
substituted with the same spacing and should be removed after one
year.
HortScience I Bartlett Consulting . Divisions of The F.A. Bartlett Tree Expert Company
2550 9th Street,Suite#112, Berkeley CA . 925.484.0211 e www.hortscience.com
Tree Removal Permit Peer Review
City of Cupertino— 19500 Pruneridge Ave., Cupertino, CA Page 4
4. Please verify that the timing for replacements would be sufficient and would ensure
a healthy tree will be grown. Please recommend specific timing for replacements.
Timing of replacement planting is not provided in the planting notes. In all likelihood, planting
will be based on the overall project schedule. If possible, planting in the fall-early winter would
take advantage of seasonal rains and reduce the potential for drought stress. Supplemental
irrigation should be provided for the new trees until they are established. This will be
especially important to planting success of the coast redwoods.
5. Please assess existing trees that are to remain and any new demolition and/or
hardscape proposed within the tree protection zone (TPZ).Assess if the applicants'
arborists need to amend their arborist report to address any impacts to the TPZ of any
existing trees that are to remain effected by the project scope—and (if needed) include
mitigated measures to impacted tree(s) if impact exceeds best practices to the TPZ
and tress health and longevity (25% impact to TPZ).
The 13 trees to remain will likely tolerate construction impacts if the Tree Preservation
Guidelines are followed and Tree Protection Zones are installed and respected. Fencing
must be installed to keep construction equipment, activities and fill outside the TPZ.
Plans call for removal of the groundcover near coast redwoods#197—200 (Photo 1). The
area between the existing be ground to a depth of 24". 1 recommend limiting the depth of
grinding to 6" within 10' of the existing trees.
v 4
e �w uTa.
a
� l � " k` Photo 1. Ground cover between curb
and fence is to be removed and the
area ground.
HortScience Bartlett Consulting Divisions of The F.A. Bartlett Tree Expert Company
2550 9`h Street,Suite#112, Berkeley CA . 925.484.0211 . www.hortscience.com
Tree Removal Permit Peer Review
City of Cupertino— 19500 Pruneridge Ave., Cupertino, CA Page 5
Summary and Recommendations
Proposed removal of 11 trees is warranted based on the project design, proposed
replacement trees will be adequate if planted in the fall and provided with reasonable after-
care. Two coast redwoods should be replaced with a more suitable species. If the
replacement species is the size of coast redwood, trees should be relocated as the current
planting site is too small. All trees should be planted in accordance with American National
Standards Institute A300 part 6 specifications for planting and Best Management Practices,
Tree Planting, 2nd Ed. (International Society of Arboriculture 2014).
Please contact me if you have any questions regarding my opinions.
Sincerely,
HortScience I Bartlett Consulting
Scott Stringer Consulting Arborist& Urban Forester
ISA Certified Arborist No. WE-5544A
ISA Tree Risk Assessment Qualified
HortScience I Bartlett Consulting . Divisions of The F.A. Bartlett Tree Expert Company
2550 9`h Street,Suite#112, Berkeley CA . 925.484.0211 . www.hortscience.com