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Arborist Report of Trees
1618 Mayflower Ave, Arcadia, CA 91006
Prepared For:
Chris Jianj
Wednesday, May 6th, 2026
(626)-766-6789
lanichkhun@gmail.com
Prepared By:
Killian Vendler, Consulting Arborist & Pest Control Advisor
(626) 740-3726 ; office@calecoarborists.com
International Society of Arboriculture # WE–14059A
Department of Pesticide Regulation PCA License #147436 and QAL #151925
ASCA Registered Consulting Arborist #889 and ASCA Tree Plant Appraisal Qualified
Chris Jianj
1618 Mayflower Ave,
Arcadia, CA 91006
Monday, May 4th, 2026
Killian Vendler | Consulting Arborist
2
Table of Contents
Assessment Summary....................................................................................................................................3
Project Overview............................................................................................................................................5
Site Conditions...............................................................................................................................................6
Figures, Tables & Attachments......................................................................................................................7
Figure 1: Satellite Map...................................................................................................................................7
Figure 2: Road Map........................................................................................................................................9
Figure 3: Site Plan........................................................................................................................................10
Figure 4: Replacement Plan..........................................................................................................................11
Proposed Action...........................................................................................................................................12
Tree Assessment...........................................................................................................................................13
Table 1: Tree Assessment.............................................................................................................................15
Tree Images..................................................................................................................................................19
Potential Project Impacts..............................................................................................................................23
Best Management Practices (BMPs)............................................................................................................24
Conclusion....................................................................................................................................................25
Arborist Signature Page...............................................................................................................................27
Chris Jianj
1618 Mayflower Ave,
Arcadia, CA 91006
Monday, May 4th, 2026
Killian Vendler | Consulting Arborist
3
Assessment Summary
Dear Chris Jianj,
You have retained my consulting arborist services to provide a tree inventory and assessment report for
the property located at 1618 Mayflower Ave, Arcadia, CA 91006, in support of your proposed
residential addition.
The subject parcel contains two (2) protected volunteer trees and no neighboring protected trees. All
trees were measured using a standard diameter tape, and the entire site and surrounding areas were
visually inspected and analyzed.
Both trees are classified as protected under the City of Arcadia Tree Preservation Regulations
(Arcadia Municipal Code, Chapter 7, Ordinance No. 2323), which prohibits the removal, relocation,
damage, or encroachment of protected oak and sycamore trees without a permit. One protected Coast
Live Oak (Quercus agrifolia) was observed to have been removed without authorization prior to this
assessment. Mitigation through replacement planting is therefore required.
To satisfy the anticipated replacement requirements and restore canopy conditions consistent with the
pre-removal site environment, two (2) 24-inch-box Coast Live Oaks (Quercus agrifolia) are
recommended for installation within the front yard, subject to final City approval. The two replacement
trees should be planted approximately 20 feet apart to provide adequate growing space for their
long-term establishment and development.
The proposed planting locations were evaluated in consideration of the existing protected Coast Live Oak
that will remain in the front yard. From an arboricultural perspective, the presence of three Coast Live
Oaks within this area does not, by itself, constitute detrimental overcrowding. Coast Live Oaks naturally
grow in association with other trees of the same species, and some future canopy and root-zone
interaction is both expected and biologically normal.
Chris Jianj
1618 Mayflower Ave,
Arcadia, CA 91006
Monday, May 4th, 2026
Killian Vendler | Consulting Arborist
4
It is recommended that a licensed and insured tree contractor complete the remaining work, including
stump removal and grinding, site preparation, and installation of the two replacement trees. Installation
should include appropriate planting depth, staking if necessary, mulching, and establishment irrigation in
accordance with accepted industry standards.
Detailed findings for each tree are provided in the Tree Assessment section of this report.
Chris Jianj
1618 Mayflower Ave,
Arcadia, CA 91006
Monday, May 4th, 2026
Killian Vendler | Consulting Arborist
5
Project Overview
Chris Jianj requested the following arboricultural services:
1. Identify all trees on the property and label them on the provided architectural drawings.
2. Evaluate current tree health and assess potential construction impacts according to the site plan.
3. Determine whether a tree protection plan is feasible for long-term retention of specific trees.
4. Evaluate the impacts and justification for proposed removals.
5. Provide justifications for the removal of protected trees where applicable.
6. Produce all compliance documentation required under the City’s Protected Tree Ordinance.
7. Deliver a formal written report with maps, photos, and required professional certifications.
Chris Jianj
1618 Mayflower Ave,
Arcadia, CA 91006
Monday, May 4th, 2026
Killian Vendler | Consulting Arborist
6
Site Conditions
⦁ The project site consists of a 14,667 sq. ft. vacant parcel with protected trees.
⦁ Two (2) trees are located on the subject property.
‒ Two (2) are protected.
‒ One (1) protected tree was found to have been removed without authorization.
⦁ The lot is flat, with street access at the front property boundary.
⦁ All trees were visually assessed for health, structure, and potential construction impacts.
Chris Jianj
1618 Mayflower Ave,
Arcadia, CA 91006
Monday, May 4th, 2026
Killian Vendler | Consulting Arborist
7
Figures, Tables & Attachments
Figures
⦁ Figure 1: Google Earth Image
⦁ Figure 2: Map
⦁ Figure 3: Site Plan
⦁ Figure 4: Replacement Plan
Tables
⦁ Table 1: Tree Assessment
Additional Documentation
⦁ Tree Photos (3 total)
Attachments
⦁ Site Plan
⦁ Topographical Survey
⦁ Letter of Determination
Chris Jianj
1618 Mayflower Ave,
Arcadia, CA 91006
Monday, May 4th, 2026
Killian Vendler | Consulting Arborist
8
Figure 1: Satellite Map
Chris Jianj
1618 Mayflower Ave,
Arcadia, CA 91006
Monday, May 4th, 2026
Killian Vendler | Consulting Arborist
9
Figure 2: Road Map
Chris Jianj
1618 Mayflower Ave,
Arcadia, CA 91006
Monday, May 4th, 2026
Killian Vendler | Consulting Arborist
10
Figure 3: Site Plan
Chris Jianj
1618 Mayflower Ave,
Arcadia, CA 91006
Monday, May 4th, 2026
Killian Vendler | Consulting Arborist
11
Figure 4: Replacement Plan
Chris Jianj
1618 Mayflower Ave,
Arcadia, CA 91006
Monday, May 4th, 2026
Killian Vendler | Consulting Arborist
12
Proposed Action
The proposed development involves constructing a residential addition on the property. Please refer to
the Architectural Site Plan (Attachment 1) for the complete layout and structural details. There are no
known easements affecting the site.
Based on the proposed building footprint, driveway access, and code-required egress pathways, one (1)
protected Coast Live Oak (Quercus agrifolia) was found to have been removed without
authorization. Pursuant to the City of Arcadia Tree Preservation Regulations (Arcadia Municipal
Code, Chapter 7, Ordinance No. 2323), removal of a protected tree requires City review and approval
and is subject to mitigation requirements as determined by the City.
Accordingly, two (2) 24-inch-box Coast Live Oaks (Quercus agrifolia) are recommended for planting
within the front yard to offset the loss of the removed protected tree and restore canopy coverage, subject
to final City approval. The replacement trees should be planted 20 feet apart to provide adequate space
for establishment and future growth.
The proposed locations were evaluated in relation to the existing protected Coast Live Oak. Based on the
available planting area and proposed configuration, the existing tree is not anticipated to prevent the
successful establishment or reasonable long-term development of the replacement trees. Proper
installation, establishment irrigation, mulching, and routine arboricultural maintenance will further reduce
the potential for excessive competition during establishment.
Chris Jianj
1618 Mayflower Ave,
Arcadia, CA 91006
Monday, May 4th, 2026
Killian Vendler | Consulting Arborist
13
Tree Assessment
This assessment is based on my site visit on May 4th, 2026, during which all trees were visually
evaluated and measured using a diameter tape. Weather conditions were clear with light cloud cover. For
clarity, all on-site trees are referenced as Tree #1 & Tree #2.
Overall, the remaining on-site protected tree (Tree #2) appears to be in fair to good condition, with no
significant structural defects observed at the time of inspection. However, Tree #1 (Coast Live Oak) was
previously removed and is documented as a protected tree removed without authorization in
association with the proposed residential addition footprint and required construction clearances. A
summary of existing site conditions and required mitigation is provided below:
● Tree #1: Coast Live Oak (Quercus agrifolia) – Protected tree removed prior to assessment without
documented City authorization; stump removal and grinding are required, followed by installation
of two (2) 24-inch box Coast Live Oaks (Quercus agrifolia) as mitigation, subject to City
approval.
All remaining protected trees proposed to stay (Tree #2) can remain structurally viable with proper
protection during construction. Required replacement ratios and mitigation measures are addressed
elsewhere in the report.
Below are the revised, polished descriptions for each tree:
Chris Jianj
1618 Mayflower Ave,
Arcadia, CA 91006
Monday, May 4th, 2026
Killian Vendler | Consulting Arborist
14
⦁ Tree #1
Quercus agrifolia–Coast Live Oak
Height: 45 ft | Spread: 30 ft
Remarks: Single-stem, total DBH 26". Health is N/A. At the time of inspection, this protected
tree was observed to have been removed prior to assessment. Based on site observations, the
removal appears to have occurred without authorization and is presumed to have been associated
with the proposed residential addition footprint and required construction clearances. Due to the
tree’s protected status under the City of Arcadia Tree Preservation Regulations (Arcadia Municipal
Code, Chapter 7, Ordinance No. 2323), mitigation is required. It is recommended that two (2)
Coast Live Oaks (Quercus agrifolia), 24-inch box, be installed, subject to City approval, to restore
canopy coverage and comply with municipal replacement requirements.
⦁ Tree #2
Quercus agrifolia–Coast Live Oak
Height: 35 ft | Spread: 35 ft
Remarks: Single-stem, total DBH 22". Health is good. This tree is protected. This tree will
remain. The tree is far enough from the proposed development that no protection is necessary.
Chris Jianj
1618 Mayflower Ave,
Arcadia, CA 91006
Monday, May 4th, 2026
Killian Vendler | Consulting Arborist
15
Table 1: Tree Assessment
Tree No. Common
Name
Botanical
Name DBH height spread
Health
Condition
rating
Protection
Status
Remove/
Preserve
1 Coast Live
Oak
Quercus
agrifolia 26″ 40′ 30′ B Yes Remove
2 Coast Live
Oak
Quercus
agrifolia 22″ 35′ 35′ A Yes Preserve
Chris Jianj
1618 Mayflower Ave,
Arcadia, CA 91006
Monday, May 4th, 2026
Killian Vendler | Consulting Arborist
16
Tree Condition Rating Descriptions:
A) Healthy, vigorous tree, reasonably free of disease, with good structure and form typical of the
species.
B) A tree with a slight decline in vigor, a small amount of twig dieback, and minor structural defects
that could be corrected.
C) A tree with moderate vigor, moderate twig and small branch dieback, thinning crown, poor leaf
color, and moderate structural defects that could be mitigated.
D) A tree in decline, with epicormic growth, extensive dieback of medium to large branches, and
significant structural defects that cannot be abated.
E) A tree in severe decline, dieback of scaffold branches and or trunk, mostly epicormic growth,
extensive structural defects that cannot be abated.
Chris Jianj
1618 Mayflower Ave,
Arcadia, CA 91006
Monday, May 4th, 2026
Killian Vendler | Consulting Arborist
17
Replacement Tree Spacing and Long-Term Suitability
The proposed planting of two 24-inch-box Coast Live Oaks (Quercus agrifolia) within the front yard
was evaluated in relation to the existing protected Coast Live Oak already growing in this area. Based on
the available planting space and proposed layout, the presence of three Coast Live Oaks within the front
yard does not create an overcrowded or unsuitable planting condition.
The two replacement oaks will be installed as 24-inch-box specimens and will establish gradually over
time. Their root systems and canopies will not immediately occupy the same space as the existing mature
tree. Based on the proposed planting locations, the existing Coast Live Oak is not expected to prevent the
replacement trees from becoming successfully established, so long as the new plantings are at least 20 feet
apart.
Some competition for sunlight, water, nutrients, and rooting space may develop as the trees mature.
With proper planting, establishment irrigation, mulching, and routine maintenance, these conditions can
be appropriately managed. If future canopy conflicts develop, they can be addressed through selective
pruning and appropriate arboricultural maintenance consistent with applicable industry standards and
City requirements.
In my professional opinion, the proposed front-yard configuration provides suitable growing conditions
for the two replacement Coast Live Oaks. The existing protected oak does not prevent their successful
establishment, and the proposed arrangement is not anticipated to adversely affect the health, structure,
or reasonable long-term development of the existing or replacement trees.
Chris Jianj
1618 Mayflower Ave,
Arcadia, CA 91006
Monday, May 4th, 2026
Killian Vendler | Consulting Arborist
18
Tree Images
Chris Jianj
1618 Mayflower Ave,
Arcadia, CA 91006
Monday, May 4th, 2026
Killian Vendler | Consulting Arborist
19
Tree #1 – Coast Live Oak (Quercus agrifolia) prior to removal and after removal
Chris Jianj
1618 Mayflower Ave,
Arcadia, CA 91006
Monday, May 4th, 2026
Killian Vendler | Consulting Arborist
20
Chris Jianj
1618 Mayflower Ave,
Arcadia, CA 91006
Monday, May 4th, 2026
Killian Vendler | Consulting Arborist
21
Tree #2 – Coast Live Oak (Quercus agrifolia)
Chris Jianj
1618 Mayflower Ave,
Arcadia, CA 91006
Monday, May 4th, 2026
Killian Vendler | Consulting Arborist
22
Potential Project Impacts
The proposed residential addition will require construction activities in proximity to existing protected
trees and will necessitate periodic access for construction vehicles and equipment. This may result in
temporary, intermittent disruptions to traffic flow along Mayflower Ave. during construction.
Additionally, the previously removed protected Coast Live Oak (Quercus agrifolia) requires stump
removal and grinding, followed by the planting of two (2) 24-inch-box Coast Live Oaks (Quercus
agrifolia). These measures are intended to address applicable City mitigation requirements and restore the
canopy contribution lost through the unauthorized removal.
The proposed front-yard replacement locations are not anticipated to create an inherently overcrowded
condition so long as they are planted over 20 feet apart. Although the replacement trees and existing
protected oak may eventually develop overlapping root zones or canopies, such interaction is normal
among compatible trees and does not, by itself, constitute an adverse impact. The replacement trees will
establish gradually, and proper planting, irrigation, mulching, and maintenance will support their
successful development.
To prevent avoidable damage to trees that will remain onsite, no construction materials, soil, debris,
equipment, or waste should be stored, placed, or staged within the dripline of any retained tree. All
construction activities conducted near retained trees should be supervised by, or performed under the
guidance of, an ISA Certified Arborist or ISA Certified Tree Worker.
Chris Jianj
1618 Mayflower Ave,
Arcadia, CA 91006
Monday, May 4th, 2026
Killian Vendler | Consulting Arborist
23
Best Management Practices (BMPs)
The tree designated for retention is located at a sufficient distance from the proposed construction
footprint and is not anticipated to be adversely impacted by project activities. Therefore, a complete Tree
Protection Plan is not required because the trees will not be affected; however, the following BMPs must
be followed to ensure no inadvertent damage occurs:
● Construction crews must be instructed not to place materials, tools, soil, trash, or equipment at
the base of any tree.
● The surrounding drip line of the tree should be avoided. This is to prevent the placement of
heavy machinery or tools that may damage the trunk or roots of the tree.
● No grading, trenching, excavation, or soil compaction should occur within the tree protection area.
● All pruning, if needed, must be performed by ISA Certified Tree Workers following ANSI A300
pruning standards.
● An ISA Certified Arborist should monitor any work occurring within proximity to a tree’s
dripline.
These measures will help maintain tree health and structural integrity throughout the construction process.
Chris Jianj
1618 Mayflower Ave,
Arcadia, CA 91006
Monday, May 4th, 2026
Killian Vendler | Consulting Arborist
24
Conclusion
You have retained my consulting arborist services to provide a tree inventory and assessment report for
the property located at 1618 Mayflower Ave., Arcadia, CA 91006, in support of the proposed residential
addition.
I inspected the property on May 4, 2026. Two protected Coast Live Oaks (Quercus agrifolia) were
identified onsite. One had already been removed prior to my inspection, while the second remains in the
front yard.
To address the prior removal, two (2) 24-inch-box Coast Live Oaks (Quercus agrifolia) are proposed as
replacement trees, subject to City approval. Both replacement trees can be accommodated within the front
yard and should be planted 20 feet apart. This spacing provides adequate room for the trees to establish
and develop without unnecessary crowding.
The existing Coast Live Oak can remain during the proposed addition. Construction should be kept away
from the tree as much as practical, particularly excavation, equipment traffic, soil stockpiling, and
material storage near its trunk and root system. No formal tree-protection fencing is proposed, but
reasonable care should be taken to avoid unnecessary root, trunk, or canopy damage during construction.
With the replacement trees planted 20 feet apart, the front yard provides adequate space for the proposed
planting. Proper irrigation during establishment, mulch, and routine maintenance should allow the new
trees to establish successfully alongside the existing Coast Live Oak. In my professional opinion, this is a
reasonable and suitable planting arrangement for the site.
Chris Jianj
1618 Mayflower Ave,
Arcadia, CA 91006
Monday, May 4th, 2026
Killian Vendler | Consulting Arborist
25
Arborist Signature Page
I, Killian Vendler, certify the following:
⦁ No warranty is made, expressed or implied, that problems or deficiencies of the trees or the
property will not occur in the future from any cause. The Arborist shall not be responsible for
damages or injuries caused by any tree defects and assumes no responsibility for the correction of
defects or tree-related problems.
⦁ The owner and client of the trees may choose to accept or disregard the Arborist's
recommendations or seek additional advice if they disagree with the Arborist's findings or
recommendations.
⦁ The Arborist has no past, present, or future interest in removing or preserving any tree. The
opinions in the Arborist report are the Arborist's independent and objective judgments.
⦁ The arborist's findings, opinions, and recommendations are based on the physical inspection of
said property. The opinions are based on knowledge, experience, and education.
⦁ The Arborist shall not be required to provide testimony, site monitoring, further documentation for
changes beyond the Arborist's control, or attend any deposition or meeting without contractual
arrangements that include additional fees for the Arborist.
⦁ The Arborist assumes no responsibility for verifying ownership or the location of property lines
or for any recommendations based on inaccurate information.
⦁ This Arborist report may not be reproduced without the express written permission of the Arborist
and the client to whom the report was provided. Any changes or alterations to this report
invalidate the entire report.
⦁ Arborists are tree specialists who use their education, knowledge, training, and experience to
examine trees, recommend measures to enhance their beauty and health, prevent or minimize
damage to trees during and after construction projects, and attempt to reduce the risk of living near
trees. Clients may choose to accept or disregard the arborist's recommendations or seek additional
advice.
⦁ Arborists cannot detect every condition that could lead to a tree's structural failure. 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
Chris Jianj
1618 Mayflower Ave,
Arcadia, CA 91006
Monday, May 4th, 2026
Killian Vendler | Consulting Arborist
26
circumstances or for a specified period. 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 service, 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 them. 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 risks associated with trees is to eliminate all trees.
Thank you for choosing my company! Feel free to contact me with any questions or concerns.
Best Regards,
Killian Vendler
(626) 740-3726
office@calecoarborists.com
ISA#WE–14059A
ASCA RCA#889
PCA License #147436
QAL #151925
ASCA TPAQ
Chris Jianj
1618 Mayflower Ave,
Arcadia, CA 91006
Monday, May 4th, 2026
Killian Vendler | Consulting Arborist