HomeMy WebLinkAboutAppendix ARBAppendix ARB
Arborist Report
ASCA Registered Consulting Arborist #401 / ISA Tree Risk Assessment Qualified / ISA Certified Arborist #WE-3172A Cell: (415) 203-0990 / Email: [email protected]
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Site Address: 493 Forbes Blvd., SSF Version: 4/24/2020
Registered Member, American Society of Consulting Arborists and Member of the International Society of Arboriculture
Walter Levison 2020 All Rights Reserved
Assessment of Four (4) Remaining Trees
At and Adjacent to the Active Demolition Site at
493 Forbes Blvd.
South San Francisco, California
Prepared for:
Aralon Properties
482 Bryant Street
San Francisco, CA 94107
Field Visit:
Walter Levison, Consulting Arborist (WLCA)
4/24/2020
Report by WLCA
4/24/2020
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ASCA Registered Consulting Arborist #401 / ISA Tree Risk Assessment Qualified / ISA Certified Arborist #WE-3172A Cell: (415) 203-0990 / Email: [email protected]
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Site Address: 493 Forbes Blvd., SSF Version: 4/24/2020
Registered Member, American Society of Consulting Arborists and Member of the International Society of Arboriculture
Walter Levison 2020 All Rights Reserved
Table of Contents
1.0 Summary __________________________________________________________________________ 3
2.0 Assignment & Background ___________________________________________________________ 4
3.0 City of South San Francisco, CA / What Trees are Protected? ______________________________ 5
4.0 Recommendations __________________________________________________________________ 6
5.0 Author’s Qualifications ______________________________________________________________ 7
6.0 Assumptions and Limiting Conditions __________________________________________________ 8
7.0 Certification ________________________________________________________________________ 9
8.0 Digital Images ______________________________________________________________________ 9
9.0 Tree Data Table ____________________________________________________________________ 16
10.0 Attached: Tree Location Map / WLCA_________________________________________________ 20
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ASCA Registered Consulting Arborist #401 / ISA Tree Risk Assessment Qualified / ISA Certified Arborist #WE-3172A Cell: (415) 203-0990 / Email: [email protected]
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Site Address: 493 Forbes Blvd., SSF Version: 4/24/2020
Registered Member, American Society of Consulting Arborists and Member of the International Society of Arboriculture
Walter Levison 2020 All Rights Reserved
1.0 Summary
Four (4) trees were assessed for this initial tree study assignment:
Tree #11 is a neighbor-owned red ironbark eucalyptus (Eucalyptus sideroxylon) located just west of the existing property line fence (see attached tree map by
WLCA). It is of large enough diameter that it is considered a protected tree per the City of South San Francisco tree ordinance under the 15.3 inch diameter
rule for “other species”. The tree is in fair overall condition, with a significant lean and lopsided canopy extending into the property survey area. The tree may
or may not be an elevated risk of failure and impact with ground targets on 493 Forbes. The tree may or may not need to be removed for safety purposes. See
WLCA’s analysis of tree condition in section 9.0 tree data table below.
Tree #12 is a Canary Island pine (Pinus canariensis) in poor overall condition that appears to be within the 493 Forbes private property bounded area (i.e.
north of the property line nearest Forbes Blvd). The tree is not protected under any of the various diameter thresholds noted in the city tree ordinance, and
can therefore be removed at this time, unless there is a special planning division condition or project approval that requires its protection during construction
(see section 3.0 below for information on protected trunk circumference and diameter thresholds). The tree exhibits visible evidence of extensive feeding by
red turpentine bark beetles which may eventually kill the tree. This tree is assumed to be proposed for removal as part of the ongoing active demolition and
construction at this location.
Tree #13 is a Monterey pine (Pinus radiata) of large enough diameter that it is considered to be a protected tree per the city tree ordinance governing tree
specimens on private lands. This tree has an overall condition rating of zero percent, which means that it is in dead condition, and needs to be removed as
soon as possible to avoid an elevated risk of tree part failure and impact with ground targets such as vehicles, pedestrians, and construction personnel on or
adjacent to the 493 Forbes property within 1 year of the date of writing. Risk of branch or limb failure and impact with the above noted targets within 1 year is
“moderate” on a scale from “low” to “extreme” (international TRAQ tree risk rating system 1). The tree appears to be jointly-owned between the City of South
San Francisco and the private lot owner (493 Forbes Blvd.), given that its trunk (mainstem) cross section straddles across the property line that runs parallel to
Forbes Blvd. (see tree map by WLCA, attached to the end of this report). Bark beetle pitch tubes and frass was found to be present along the lowermost 6 feet
of the mainstem.
Tree #14 is also a Monterey pine (Pinus radiata) of large enough diameter that it is considered to be a protected tree per the city tree ordinance governing
tree specimens on private lands. This tree has an overall condition rating of 10% out of a possible 100%, which means that it is in very poor condition, but
realistically almost dead, and needs to be removed as soon as possible to avoid an elevated risk of tree part failure and impact with ground targets such as
vehicles, pedestrians, and construction personnel on or adjacent to the 493 Forbes property within 1 year of the date of writing. Risk of branch or limb failure
and impact with the above noted targets within 1 year is “moderate” to “high” (depending on the diameters of the branches and limbs most likely to fail 2) on a
scale from “low” to “extreme”, given that the Genentech Transportation Department is located literally adjacent to the east side of the 493 Forbes demolition
and construction site, with hundreds of passenger buses entering and exiting all day along the north-south oriented property entrance driveway over which this
tree’s canopy extends (refer again to the international TRAQ tree risk rating system 3). Over time, the tree’s risk rating for tree part failure and impact with
passenger buses may increase to “high” as the wood tissues become increasingly desiccated. The tree appears to be owned by Genentech, with the
1 2017. Dunster et al. Tree Risk Asssessment Manual, 2nd Edition. International Society of Arboriculture. Champaign, Illinois, USA. 2 WLCA was not requested to prepare a tree risk analysis for any tree in this written arborist report. The TRAQ risk ratings di scussed in this report were provided as a quick
reference so that the property owners and managers of the site can determine how to proceed with long term tree management, based on a background understanding of risks
presented by the study trees. A more complete written analysis of 493 Forbes site tree risk and neighbor tree risk by WLCA can be prepared in the future upon request. 3 2017. Dunster et al. Tree Risk Asssessment Manual, 2nd Edition. International Society of Arboriculture. Champaign, Illinois, USA.
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Site Address: 493 Forbes Blvd., SSF Version: 4/24/2020
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mainstem growing just east of 493 Forbes Blvd. on the Genentech Transportation Department property (not verified). Refer to the tree map by WLCA,
attached to the end of this report. Removal would therefore require coordination with the tree owner as well as approval of a tree removal permit by the City of
South San Francisco.
2.0 Assignment & Background
Walter Levison, Consulting Arborist (WLCA) was directed to tag and assess all remaining trees located adjacent to the property line bounding the
rectangular demolition and construction area at 493 Forbes, SSF (see WLCA tree map markup attached, with the tree study area shown as bounded within
a magenta highlighted line). Some of the trees are within the private property, while others appear to be straddling the property line, or growing just outside
the 493 Forbes Blvd. lot on neighbors’ properties. None of the trees along the railroad property lot north of the 493 Forbes site were assessed.
The four study trees were tagged with racetrack-shaped aluminum numbered tags #11, 12, 13, and #14 affixed to the trunk of each tree at roughly eye level.
These tags correspond to the numbers on the attached tree location map markup.
WLCA summarized the tree situation from a long-term site manager’s perspective in section 1 of the report.
No formalized tree protection recommendations were provided in this report, given that all four of the trees all appear to be in need of removal for safety
purposes. However, WLCA is aware that removal of certain trees may be difficult or impossible, given their positions on neighboring properties (i.e. trees #11
and #14). Therefore, a spec image of a “trunk buffer wrap” is provided by WLCA showing the standard best management practice for protection of the
above-ground mainstem of a tree on or near a construction site.
Digital images of the trees archived by WLCA are included below in this report for reference of existing conditions.
The tree data table with detailed tree information makes up section 9.0 of this report. WLCA used a forester’s D-tape to determine trunk diameter at 4.5 feet
above grade, or at a narrow point below a mainstem fork if the fork or if a bulge occurs at 4.5 feet above grade. The D-tape converts actual trunk
circumference into averaged diameter in inches and tenths of inches. Tree heights were determined using a digital Nikon Forestry Pro 550 rangefinder and
hypsometer. Tree canopy spreads were visually estimated or paced out by foot.
Tree tag numbers are noted on the WLCA tree map markup attached to the end of this written report as section 10.0.
Note that tree risk assessment for site trees and/or neighbor-owned trees was not part of this initial assignment. WLCA has included some basic risk ratings
in this arborist report, based on a quick analysis of the existing conditions found during his field visit. However, a more complete analysis of risk, with more
detailed TRAQ tree risk ratings, would require a separate additional report to be prepared (outside the scope of this initial assignment).
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ASCA Registered Consulting Arborist #401 / ISA Tree Risk Assessment Qualified / ISA Certified Arborist #WE-3172A Cell: (415) 203-0990 / Email: [email protected]
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Site Address: 493 Forbes Blvd., SSF Version: 4/24/2020
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3.0 City of South San Francisco, CA / What Trees are Protected?
What is a "protected tree"? The following information is pasted from the official City of South San Francisco website which summarizes the city
tree ordinance wordage:
• Any tree of the following species with a circumference of 75" or more when measured 54" above natural grade
(Approx. 24 inches diameter)
o Blue Gum (Eucalyptus globulus)
o Black Acacia (Acacia melanoxylon)
o Myoporum (Myoporum laetum)
o Sweetgum (Liquidambar styraciflua)
o Glossy Privet (Lingustrum lucidum)
o Lombardy Poplar (Populus nigra)
• Any heritage tree of the following species with a circumference of 30" or more when measured at 54" above natural grade
(Approx. 9.6 inches diameter)
o California Bay (Umbellaria californica)
o Oak (Quercus spp.)
o Cedar (Cedrus spp.)
o C alifornia Buckeye (Aesculus californica)
o Catalina Ironwood (Lyonothamnus floribundus var. asplenifolius)
o Strawberry Tree (Arbutus spp.)
o Mayten (Maytenus boaria)
o Little Gem Dwarf Southern Magnolia (Magnolia grandiflora 'Little Gem')
• Any tree other than the species listed above with a circumference of 48" or more when measured 54" above natural grade
(Approx. 15.3 inches diameter)
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ASCA Registered Consulting Arborist #401 / ISA Tree Risk Assessment Qualified / ISA Certified Arborist #WE-3172A Cell: (415) 203-0990 / Email: [email protected]
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Site Address: 493 Forbes Blvd., SSF Version: 4/24/2020
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4.0 Recommendations
1. Remove tree #11 for safety purposes (neighbor-owned tree west of 493 Forbes). If the tree cannot be
removed, then maintain protection in the form of a trunk buffer wrap per the image at right, and/or chain link
fencing protection along the property line. The tree is currently not irrigated, but would benefit significantly
from regular (1x/weekly) heavy irrigation over the open soil root zone.
Volume of water per week recommended: 50 to 100 gallons.
This tree is both a neighbor tree and a protected-status tree.
2. Remove tree #12 (a private tree in poor overall condition, smaller in diameter than threshold for “protected
tree”). This tree does not appear to require a tree removal permit, unless there is a planning division project
condition of approval that requires for some reason that it be retained and protected in place (PIP).
3. Remove tree #13, a dead tree that is jointly-owned by the City of South San Francisco and the owner of the lot
known as 493 Forbes Blvd. Although the tree is a protected-size specimen, a tree that is verified to be in dead
condition should be considered an elevated risk of tree part or total tree failure and impact with ground targets
(TRAQ risk rating system), and as such is likely deemed a “hazard” or similar designation per the City’s own
tree removal permitting criteria system, which may or may not allow for a “waived fee” type over-the-counter
removal permit issuance. Contact City Staff to verify and determine a course of action for removal permitting.
On a final note: As of today, this tree is rated to be of “moderate” risk of tree part failure and impact with
ground targets within 1 year, but as the wood (mainstem, limbs, branches, twigs) desiccates over time, the
tree risk rating may increase to “high” risk.
4. Remove tree #14 for safety purposes as soon as possible. This tree is in 10% overall condition (“very poor”): a
rating designation that ranges from 6% to 20% overall condition. 10% condition means that the tree is at the lower end of the “very poor” rating range of
values, and is nearing death. As with trees #11 and #13, this tree is also a protected-status tree, and may or may not be removable by over-the-counter
permit given its condition rating of 10%. This tree appears to be on land owned by Genentech, and is located on the driveway of the Genentech
Transportation Division services driveway where hundreds of passenger buses travel daily. Contact the property owner to discuss a removal strategy. As
with tree #13, risk of tree part or total tree failure will increase over time as the wood tissues desiccate. Current risk of tree part or total tree failure and
impact with Genentech buses within 1 year of the date of writing is “moderate” to “high” (the rating varies due to the various diameters of tree limbs and
branches that are likely to fail over the driveway of the Genentech Transportation Department).
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ASCA Registered Consulting Arborist #401 / ISA Tree Risk Assessment Qualified / ISA Certified Arborist #WE-3172A Cell: (415) 203-0990 / Email: [email protected]
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Site Address: 493 Forbes Blvd., SSF Version: 4/24/2020
Registered Member, American Society of Consulting Arborists and Member of the International Society of Arboriculture
Walter Levison 2020 All Rights Reserved
5.0 Author’s Qualifications
• Continued education through The American Society of Consulting Arborists, The International Society of Arboriculture (Western Chapter), and
various governmental and non-governmental entities.
• Contract Town Arborist, Town of Los Gatos, California
Community Development Department / Planning Division
2015-present
• Tree Risk Assessment Qualified (ISA TRAQ Course Graduate, Palo Alto, California)
• Millbrae Community Preservation Commission (Tree Board)
2001-2006
• ASCA Registered Consulting Arborist #401
• ASCA Arboriculture Consulting Academy graduate, class of 2000
• Associate Consulting Arborist
Barrie D. Coate and Associates
4/99-8/99
• Contract City Arborist, City of Belmont, California
Planning and Community Development Department
1999-2020
• ISA Certified Arborist #WE-3172A
• Peace Corps Soil and Water Conservation Extension Agent
Chiangmai Province, Thailand 1991-1993
• B.A. Environmental Studies/Soil and Water Resources
UC Santa Cruz, Santa Cruz, California 1990
UCSC Chancellor’s Award, 1990
(My full curriculum vitae is available upon request)
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ASCA Registered Consulting Arborist #401 / ISA Tree Risk Assessment Qualified / ISA Certified Arborist #WE-3172A Cell: (415) 203-0990 / Email: [email protected]
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Site Address: 493 Forbes Blvd., SSF Version: 4/24/2020
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6.0 Assumptions and Limiting Conditions
Any legal description provided to the consultant/appraiser is assumed to be correct. Any titles and ownership to any property are assumed to be good and marketable. No responsibility is assumed
for matters legal in character. Any and all property is appraised and evaluated as through free and clean, under responsible ownership and competent management.
It is assumed that any property is not in violation of any applicable codes, ordinance, statutes, or other government regulations.
Care has been taken to obtain all information from reliable sources. All data has been verified insofar as possible; however, the consultant/appraiser can neither guarantee nor be responsible for
the accuracy of information provided by others.
The consultant/appraiser shall not be required to give testimony or to attend court by reason of this report unless subsequent contractual arrangements are made, including payment of an
additional fee for such services as described in the fee schedule and contract of engagement.
Unless required by law otherwise, the possession of this report or a copy thereof does not imply right of publication or use for any other purpose by any other than the person to whom it is
addressed, without the prior expressed written or verbal consent of the consultant/appraiser.
Unless required by law otherwise, neither all nor any part of the contents of this report, nor copy thereof, shall be conveyed by anyone, including the client, to the public through advertising, public
relations, news, sales, or other media, without the prior expressed conclusions, identity of the consultant/appraiser, or any reference to any professional society or institute or to any initiated
designation conferred upon the consultant/appraiser as stated in his qualifications.
This report and any values expressed herein represent the opinion of the consultant/appraiser, and the consultant’s/appraiser’s fee is in no way contingent upon the reporting of a specified value, a
stipulated result, the occurrence of a subsequent event, nor upon any finding to be reported.
Sketches, drawings, and photographs in this report, being intended for visual aids, are not necessarily to scale and should not be construed as engineering or architectural reports or surveys
unless expressed otherwise. The reproduction of any information generated by engineers, architects, or other consultants on any sketches, drawings, or photographs is for the express purpose of
coordination and ease of reference only. Inclusion of said information on any drawings or other documents does not constitute a representation by Walter Levison to the sufficiency or accuracy of
said information.
Unless expressed otherwise:
a. information contained in this report covers only those items that were examined and reflects the conditions of those items at the time of inspection; and
b. the inspection is limited to visual examination of accessible items without dissection, excavation, probing, or coring. There is no warranty or guarantee, expressed or implied, that
problems or deficiencies of the plants or property in question may not arise in the future.
Loss or alteration of any part of this report invalidates the entire report.
Arborist Disclosure Statement:
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. Clients may choose to accept or disregard the recommendations of the arborist, or to seek additional advice.
Arborists cannot detect every condition that could possibly lead to the structural failure of a tree. Tree are living organisms that fail in ways we do not fully understand. Conditions are often hidden
within trees and below ground. Arborist cannot guarantee that a tree will be healthy or safe under all circumstances, or for a specified period of time. Likewise, remedial treatments, like any
medicine, cannot be guaranteed.
Treatment, pruning, and 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 other issues. Arborists cannot take such considerations into account unless complete and accurate information is disclosed to the arborist. An arborist should then be expected to
reasonably rely upon the completeness and accuracy of the information provided.
Trees can be managed, but they cannot be controlled. To live near trees is to accept some degree of risk. The only way to eliminate all risk associated with trees is to eliminate the trees.
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ASCA Registered Consulting Arborist #401 / ISA Tree Risk Assessment Qualified / ISA Certified Arborist #WE-3172A Cell: (415) 203-0990 / Email: [email protected]
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Site Address: 493 Forbes Blvd., SSF Version: 4/24/2020
Registered Member, American Society of Consulting Arborists and Member of the International Society of Arboriculture
Walter Levison 2020 All Rights Reserved
7.0 Certification
I hereby certify that all the statements of fact in this report are true, complete, and correct to the best of my knowledge and
belief, and are made in good faith.
Signature of Consultant
Walter Levison
8.0 Digital Images
WLCA archived images of the survey trees on 4/24/2020
Tag # Image Tag # Image
11
Lean to the southeast.
11
Roots along the property line appear to have been deflected by a
historical curb that was demolished recently.
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11
11
Canopy lopsided southeast over 493 Forbes.
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12
12
12
Red turpentine bark beetle frass and pitch tubes. This tree will likely die
prematurely due to this attack.
13
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13
13
Close-up of bark beetle pitch tube near base of tree #13.
13
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ASCA Registered Consulting Arborist #401 / ISA Tree Risk Assessment Qualified / ISA Certified Arborist #WE-3172A Cell: (415) 203-0990 / Email: [email protected]
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Site Address: 493 Forbes Blvd., SSF Version: 4/24/2020
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14
Genentech Transporation building address for reference.
Tree in this image is not tree #14.
14
Buses ingress and egress under the canopy of tree #14 all day.
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9.0 Tree Data Table
Tree Tag Number Genus & Species
(PROTECTED
STATUS NOTED
WHERE
APPLICABLE)
Common Name Trunk1 Diameter Trunk2 Diameter Trunk3 Diameter Sum of All Trunk Diameters Height & Canopy Spread (Ft.) Health & Structural Rating (100% Each) Overall
Condition
Rating
(0 to 100%) (R)emove Tree (S)ave Tree (D)isposition Unclear Tree Conservation Suitability Ratings (TPS) Notes MAINTENANCE AND PROTECTION CODES 11
Eucalyptus
sideroxylon
NEIGHBOR TREE
PROTECTED
STATUS
Red
ironbark
eucalyptus
29.1 -- -- 29.1 40/50 65/45 50% Fair X Poor
Good live twig density and
extension in upper elevations.
Remaining foliage and live
wood is in uppermost 1/3 of
the tree canopy. Trunk leans
southeast. Canopy lopsided
southeast. Prevailing wind
appears to blow
east/southeast in direction of
trunk lean. Old curb appears
to have been demolished.
Root system on grade has
deflected along this on north-
south oriented curb line.
Buttress root flares seem to
be lacking on east side of tree
(lean side/compression side),
which seems to indicate
possible instability issue.
However, the trunk does right
to vertical at 12 feet above
grade, which suggests the
tree root plate has stabilized
(not verified).
From a tree risk manager’s
perspective, this tree’s likely
asymmetrical root plate and
lean/lopsidedness issues
suggest elevated risk of tree
failure that warrants removal.
However, it is owned by the
neighbor to the east.
If tree is
retained, use
trunk buffer
wrap, and 50
to 100 gallons
of irrigation
water per
each week
over the open
soil root zone.
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Tree Tag Number Genus & Species
(PROTECTED
STATUS NOTED
WHERE
APPLICABLE)
Common Name Trunk1 Diameter Trunk2 Diameter Trunk3 Diameter Sum of All Trunk Diameters Height & Canopy Spread (Ft.) Health & Structural Rating (100% Each) Overall
Condition
Rating
(0 to 100%) (R)emove Tree (S)ave Tree (D)isposition Unclear Tree Conservation Suitability Ratings (TPS) Notes MAINTENANCE AND PROTECTION CODES 12
Pinus
canariensis
SITE TREE
NON-
PROTECTED
STATUS
Canary
Island pine 9.5 -- -- 9.5 22/12 30/30 30% Poor X Poor
Tree is assumed to be
removed as part of the site
redevelopment work currently
on-going.
Tree located on private land.
Tree is of non-protected size,
and can be removed without a
city tree removal permit,
unless there is a condition of
project approval that states
that this tree must be
protected in place, which
would supercede the tree
ordinance.
Red turpentine bark beetle
feeding (RTBB) is evidenced
by beetle frass on ground
surrounding the entire
circumference of the trunk
base (see photos). This pest
usually kills its host
prematurely. Therefore, this
tree will likely die within the
next year or two, irrespective
of the ongoing site
construction work.
n/a draft
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Tree Tag Number Genus & Species
(PROTECTED
STATUS NOTED
WHERE
APPLICABLE)
Common Name Trunk1 Diameter Trunk2 Diameter Trunk3 Diameter Sum of All Trunk Diameters Height & Canopy Spread (Ft.) Health & Structural Rating (100% Each) Overall
Condition
Rating
(0 to 100%) (R)emove Tree (S)ave Tree (D)isposition Unclear Tree Conservation Suitability Ratings (TPS) Notes MAINTENANCE AND PROTECTION CODES 13
Pinus radiata
JOINT-OWNED
CITY/PRIVATE
TREE
PROTECTED
STATUS
Monterey
pine 37.2 -- -- 37.2 55/45 0/0 0% DEAD X Poor
Most of the lower elevation
limbs have been recently
removed, assumedly due to
death of those limbs. Needles
100% brown throughout the
canopy (see photos). Elevated
risk of tree and tree part
failure and impact with
personnel and Genentech
buses. Lowermost 6 feet of
trunk exhibit both RTBB frass
and pitch tubes, indicating a
significant infestation that
was likely the main “cause” of
death, though in reality, it
was more a combination of
lack of irrigation, bark
beetles, and possibly also
pine pitch canker fungus
infection (not verified).
This tree appears to be
straddling the south property
boundary line, which means
that it is jointly owned by
both the city and by the 493
Forbes property owner. This
may or may not complicate
tree removal permitting.
Given that the tree is
completely dead, and that it
presents a known elevated
risk of failure and impact with
ground targets, a tree
removal permit will likely be
granted quickly by the city.
n/a
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Site Address: 493 Forbes Blvd., SSF Version: 4/24/2020
Registered Member, American Society of Consulting Arborists and Member of the International Society of Arboriculture
Walter Levison 2020 All Rights Reserved
Tree Tag Number Genus & Species
(PROTECTED
STATUS NOTED
WHERE
APPLICABLE)
Common Name Trunk1 Diameter Trunk2 Diameter Trunk3 Diameter Sum of All Trunk Diameters Height & Canopy Spread (Ft.) Health & Structural Rating (100% Each) Overall
Condition
Rating
(0 to 100%) (R)emove Tree (S)ave Tree (D)isposition Unclear Tree Conservation Suitability Ratings (TPS) Notes MAINTENANCE AND PROTECTION CODES 14
Pinus radiata
PRIVATE TREE
ON
GENENTECH
TRANSPOR-
TATION DEPT.
PROPERTY
PROTECTED
STATUS
Monterey
pine 27.0 -- -- 27.0 45/50 10/10
10%
Very
Poor
X Poor
Most of the lower elevation
limbs have been recently
removed, assumedly due to
death of those limbs. Needles
in canopy are 70% brown,
30% green (see photos).
Elevated risk of tree and tree
part failure and impact with
personnel and Genentech
buses. Lowermost 6 feet of
trunk exhibit both RTBB frass
and pitch tubes, indicating a
significant infestation that
will soon kill the tree
prematurely (i.e. within 1
year). Risk of tree and/or tree
part failure and impact with a
Genentech bus within 1 year
is “moderate” to “high”.
Therefore, removal of the tree
is highly recommended at this
time.
This tree appears to be
owned by the Genentech,
which may greatly complicate
tree removal permitting.
Given that the tree is nearly
dead, and that it presents a
known elevated risk of failure
and impact with buses and
other targets, a tree removal
permit will likely be granted
quickly by the city if permit
processing were to be
initiated by the tree owner.
n/a
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ASCA Registered Consulting Arborist #401 / ISA Tree Risk Assessment Qualified / ISA Certified Arborist #WE-3172A Cell: (415) 203-0990 / Email: [email protected]
20 of 20
Site Address: 493 Forbes Blvd., SSF Version: 4/24/2020
Registered Member, American Society of Consulting Arborists and Member of the International Society of Arboriculture
Walter Levison 2020 All Rights Reserved
10.0 Attached: Tree Location Map / WLCA
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