TR-2012-10b OFFICE OF COMMUNITY DEVELOPMENT
CITY HALL
10300 TORRE AVENUE •CUPERTINO, CA 95014-3255
C U P E RT 1 N t? (408) 777-3308 • FAX (408) 777-3333• �lanning�a�cupertino.org
Apri14, 2012
Navin Jethani
1187 Gardenside Ln
Cupertino, CA 95014
SUBJECT: HAZARDOUS TREE REMOVAL PERMIT ACTION LETTER- Application TR-2012-10
This letter confirms the decision of the Director of Community Development, given on April 4, 2012,
approving a tree removal permit to allow the removal and replacement of one (1) Flooded Gum (Eucal�ptus
rudis) and four (4) Tasmanian blue gum (Eucal�ptus globulus) trees (ranging from 10" to 27" in diameter).
All trees are part of an approved landscaping plan at an existing Planned Residential Development located
at 1187 Gardenside Lane. The application is approved with the following conditions:
1. APPROVED PROTECT
This approval is based on the arborist report prepared by Michael Bench (Certified Arborist WE-1897),
dated February 22, 2012, consisting of 3 pages and entitled:An Evaluation of Five Eucalyptus Trees at 1187
Gardenside Lane, Cupertino, CA" except as may be amended by conditions in this resolution.
2. TREE REPLACEMENTS
The applicant will be required to plant nine (9), 24 box replacement trees, to include five (5) fruit trees
„
and four (4) Japanese Maple trees on the property in accordance with the Protected Tree Ordinance,
arborist report, and approved replacement plan. The replacements shall be planted within 30 days of
the effective approval date of this tree removal permit.
3. PROTECTED TREE COVENANT
The applicant shall be required to record a covenant recording the replacement trees as protected trees
within 30 days of planting the replacement trees in accordance with the City's Protected Trees
Ordinance. Failure to do so may result in code enforcement and/or administrative citations.
Staff has made the findings necessary to grant the tree removal permit in accordance with Section 14.18.180
of the Protected Trees Ordinance.
Sincerely,
a
Simon Vuong
Assistant Planner
(408) 777-1356
simoi�v@,cu��ertino.or�
AN EVALUATION OF FIVE EUCALYPTUS TREES
AT 1187 GARDENSIDE LANE ��C��VED
CUPERTINO, CALIFORNIA
Assignment �Y: �� —
I was asked by Mr. Simon Vuong, Planner, City of Cupertino, to review 5 eucal�yptus
trees located 1187 Gardenside Lane, Cupertino, California.
Observations
I visited the site on February 10, 2012.
The five eucalyptus trees are located in a row on the south side of the property adjacent to
the property boundary. Three of the eucalyptus trees are located in the front yard. Two
are located in the side yard behind the fence to the back yard. The side yards (both the
north and south sides) and the back yard is completely covered by concrete, with the
exception of 3 foot round holes, in which 7 coast redwood trees (Sequoia sempervirens)
and two of the five eucalyptus trees exist. In the back yard, there is also one cork oak
(Quercus suber) in a small raised planter.
The first tree nearest the street, Gardenside Lane, is a Flooded Gum (Eucalyptus rudis).
The other four specimens are Tasmanian blue gum (Eucalyptus globulus). The
differences between these species are not significant with regard to their use at this
property. The trunk diameters of these trees starting with the specimen (Flooded Gum)
nearest the street are 27 inches, 25 inches, 13 inches, 10 inches, and 19 inches DBH
(Diameter at Breast Height= 54 inches above grade). The canopies are all approximately
50 feet in height and the canopy spread of each specimen ranges between 20-35 feet.
These 5 eucalyptus tree are relatively young.
All 5 of these trees have been"Topped" in the past, likely in an attempt to reduce their
height under the assumption that they would be less likely to fail and, therefore, safe.
Unfortunately this logic only applies to the short term. As new branches emerge from the
stub cut limbs, they emerge from the buds, which exist only in the current year's growth
ring. This means that all of the new branches are only attached to the outer layer of wood,
approximately 1/16 inch in thickness and are not effectively attached to the interior wood.
The new branches typically grow very vigorously and produce a dense compliment of
leaves, which are very heavy because of their mass and ability to retain moisture. The
result is that their structure is highly prone to failure.
The homeowner provided photos of limbs, which have fallen in their yard and in the
neighbor's yard. This is not surprising and was in fact predictable. The side yard of each
of these properties is approximately 10 feet. Consequently, the risk of damage to either
of the two residences is quite high.
In my experience, unaltered (not"Topped") Tasmanian blue gum spe��es (Eucalyptus ,
globulus) and the Flooded Gum gum (Eucalyptus rudis) are prone to "f�mb�rvp" u�hich .�'�—�`��-��
�"'��v�
sometimes occurs unexpectedly even by a trained arborist. Thus, limb drop by many
eucalyptus species, including these, is highly unpredictable. However, limb drop by
"topped" specimens is indeed expected and is highly predictable.
Discussion
"Topped" eucalyptus trees, including these two species, can sometimes be managed by
regular pruning or"re-topping" but this pruning must be done every 2 years and must be
done for the life of the tree. This does not eliminate the risk of branch failures, but it does
' usually reduce the risk of damage, because regularly pruned branches that fail are usually
fairly small.
Regular pruning (for the life of the tree) is sometimes a management option, provided
that the potential targets have relatively low value or would not be constantly present (for
example, in the back of a property away from structures) or in cases, in which the
tolerances of the homeowner(s) are high (i.e, the drop of an occasional small branch
could be tolerated). This is not the case at this site. The homeowner states that the
neighbor to the south has threatened litigation should branches fall in their yard again or
should damage their residence.
Conclusions
The five "topped" eucalyptus trees pose a very high risk of failure. Management by
regular pruning is a good solution at locations where the targets are rarely present (i.e, an
area rarely used in a park well away from pathways), where the targets have relatively
low value (i.e., an wooden fence or an old unused shed), or where the owners accept the
risk of small branch failures.
At this location, the trees are located between residences, posing a risk to both residences,
and the residents of both sites have little or no tolerance. In this case, management by
pruning is not a solution, in my opinion.
Recommendations
1. I recommend that the application to remove these 5 eucalyptus trees be approved.
2. Because of the concrete in the side yard around 2 of the specimens, it would not
be possible to grind the stumps of those two specimens, without removing large
sections of the concrete. Also, it would not be possible to plant replacement trees
in the back yard because concrete covers the entire area except for the holes for
the coast redwood trees. I advised the homeowner that they should expect
damage to the concrete in the relatively near future.
3. Replacement specimens could be planted in the front yard near the south property
boundary. However, the space is relatively small and could not support large
trees, but trees that grow relatively small could be planted as replacements. One
replacement specimen could be planted in an empty 3 foot hole in the concrete on
the south side yard.
4. I recommend any of the following "small tree" species as replacements:
Dwarf Olive ( Olea europea'Skylark')
Hybrid madrone (Arbutus `Marina')
Saucer magnolia(Magnolia soulangiana)
Crape myrtle (Lagerstromia indica)
Western redbud (Cercis occidentalis)
African sumac (Rhus lancea)
Carob (Ceratonia siliqua) (gets to about 40 feet but it takes pruning very well
and can easily be kept to 20 feet.)
Grecian laurel (Laurus nobilis)
Japanese maple (Acer palmatum - a Standard Green or a Coral bark
('Sango Kaku') - these are two of the most reliable for this area.
Trident maple (Acer buegerianum)
Vine maple (Acer circinatum)
Full Moon maple (Acer japonicum 'Vitifolium�
No common name (Acer truncatum)
Flaxleaf Paperbark (Melaleuca linarifolia)
5. The homeowner requested"Fruiting" replacement trees. Most fruit trees require
considerable care and maintenance, which may involve the use of pesticides
regularly. In my opinion, most urban dwellers are not prepared to commit the time
and do not have the expertise to effectively grow fruit trees. The lady of the house
specifically requested Pineapple Guava(Feijoa sellowiana), but this species
typically never becomes large enough to be considered a tree.
The only fruiting tree that I can recommend is Persimmon (Diospyros kaki),
which is relatively trouble free once established.
Respectfully submitted,
.,
�_
Michael L. Bench, Consulting Arborist
International Society of Arboriculture Certification #WE 1897
American Society of Consulting Arborists Member