2nd Aborist Report TR-2018-32 (Alive)_2 (1)Arborist Report for
Cupertino City Center - C9A Common Area
Prepared by Sarah Hon Gaskin ISA Certified Arborist #WE-9519A
3490 Buskirk Ave Pleasant Hill, CA 94523
(866) 815-2525
sarah@aplustree.com
www.aplustree.com Prepared on July 5, 2018, edited on 8/10/18
Background
Information
This report is concerning two (2) trees located at 20450 Stevens Creek Boulevard, Cupertino, CA.
The property is known as Cupertino City Center, owned and managed by Prometheus. For the
remainder of this report, Cupertino City Center will be referred to as the “client” property.
Assignment (and
any limiting
factors)
I was asked to evaluate two (2) trees; I was to review their health, structural integrity and make a
recommendation:
1.Acer saccharinum (Silver maple), 7.8” DBH
2.Acer saccharinum (Silver maple), 8.7” DBH
Observations
Acer saccharinum #1 is located along an unnamed service road that connects Stevens Creek Boulevard
to Cali Avenue within the client’s property. The tree is adjacent to a building and parking lot. The tree
is growing in an approximately 2’x2’ square planting well with a metal grate at the base of the tree.
The tree was planted below grade.
Please see photos in Attachment 1 for further observations.
Acer saccharinum #2 is located at the corner of Stevens Creek Boulevard and an unnamed service road
that connects Stevens Creek Boulevard to Cali Avenue within the client’s property. The tree is adjacent
to a building and parking lot. The tree is growing in an approximately 2’x2’ square planting well with a
metal grate at the base of the tree. The tree was planted below grade.
Please see photos in Attachment 2 for further observations.
Testing and
Analysis
There were no soil, tree or other physical testings.
Discussion
Acer saccharinum #1 and #2 are both outgrowing the area of their planting well on the sidewalk. Both
of these trees are growing into the planting grate. These grates are made of cast iron, and must
remain on the planting well at the client’s request to protect pedestrians. The roots of these trees are
growing in the planting well in such a manner that the roots are pushing up against the tree grate, and
making the surface unlevel. After consulting with Andrew Sabol, landscape architect and engineer with
Ironsmith Architectural Products, it was determined the best management practice to level the cast
1
iron grate would be to remove the trees and replant with a new, young tree.We determined a
pedestrians path of travel is interrupted when the grate is unlevel, and Mr. Sabol was unable to
provide an alternative method for stabilizing and leveling the tree grates. Andrew Sabol:
asabol@ironsmith.biz or (760) 776-5080
By removing the current tree roots, the grates would return to be level with the sidewalk, since the
grates would no longer be interfered by the roots. Root pruning is not an option because the roots are
mature and contribute to the overall survival of the maples. If the roots were pruned, the trees would
ultimately die. The client had informed A Plus of a previous attempt to prune the roots by a
landscaper. The root pruning treatment was not successful, and the trees roots continue to grow
within the planting well, disrupting the protective grate and hardscape. An additional root pruning
would not prevent further hardscape damage.
New trees planted in these tree grates should begin routine tree growth regulator and root pruning
treatments so similar effects to the grate do not occur in the future. Additionally, both of these trees
are causing hardscape damage to the surrounding pavement and fire lane. Acer saccharinum #1 and
#2 are causing damage to the property through hardscaping damage of the concrete and making the
grate unlevel, posing a danger to pedestrians using the sidewalk area. The client must maintain even
walking surface for pedestrian path of travel.
Recommendations
The recommendation is that these two (2) trees be removed from the landscape, and be replaced
with two (2) Acer saccharinum 24” box trees in the same location. Locations of the removal and
replacement locations are in the Attachments I below.
A Plus recommends removing the two (2) trees stated above.
Attachment I
Tree 1
Acer saccharinum (Silver
maple), 7.8” DBH
Street view of Acer
saccharinum #1
Tree 1
Acer saccharinum (Silver
maple), 7.8” DBH
Overall structure of tree
2
Unlevel grate over planting
well
3
4
Attachment 2
Tree 2
Acer saccharinum (Silver
maple), 8.7” DBH
Street view of Acer
saccharinum #2 showing
overall structure
5
Tree 2
Acer saccharinum (Silver
maple), 8.7” DBH
Grate at the base of Acer
saccharinum #2, unlevel
and unstable grate. This
area is used by pedestrians
using the sidewalk.
6
Tree 2
Acer saccharinum (Silver
maple), 8.7” DBH
Unlevel planting grate
posing a hazard to
pedestrians.
Acer saccharinum #2
causing hardscape damage
along the fire lane and
sidewalk.
7
Location of Trees to be
removed
5. Acer saccharinum (Silver maple), 7.8” DBH
6. Acer saccharinum (Silver maple), 8.7” DBH
8
Replacement Species
Trees
(see map below)
1.Acer saccharinum - Silver Maple 24” Box
2.Acer saccharinum - Silver Maple 24” Box
9