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HomeMy WebLinkAboutTR_Arborist_Report_170515_v1 Arborist Report Prepared for: Franklin Ng Architectural Werks, Inc. 11416 98th Ave NE Kirkland, WA 98033 Prepared by: Kyle Henegar ISA Certified Arborist PN6445A ISA Tree Risk Assessment Qualified Member, American Society of Consulting Arborists Tree Inventory Renton Dental Arts May 1, 2017 Kyle Henegar, Certified Arborist PN6445A Page 2 of 10 Table of Contents Assignment Limits of the Assignment Methodology Observations Discussion Recommendations Tree Protection Measures Glossary Certificate of Performance Waiver of Liability Appendix A: Photos Appendix B: Site Plan w/ Numbered Trees Assignment On April 25, 2017, Franklin Ng requested a Tree Retention Plan (Tree Inventory) per the City of Renton Submittal Requirements-Site Plan Review. Limits of the Assignment This report is not intended as and does not represent legal advice and should not be relied upon to take place of such advice. This report is based on my site visit on April 28, 2017. This is a Visual Tree Assessment. The tools used in this report were limited to a diameter tape measure and a camera. Methodology These trees were measured at Diameter at Breast Height (DBH). DBH is a standard measure of a treeʼs size and is most often taken at 4.5 feet from the base of the tree; however, this can vary depending on a tree’s individual characteristics, such as if there are multiple trunks or if the tree is growing on a slope. The measurements used in this report are according to Seattle DPD Directors Rule 16-2008. Radial Drip Line (RDL) is defined as the outer most circumference of a tree’s canopy where water drips from and onto the ground. This measurement is often used to define the optimum Tree Protection Area for trees during construction. The RDL is included for each tree in this inventory. The trees identified in this report were visually inspected for defects and vigor. A standard process of assessing a tree is termed a Visual Tree Assessment (VTA). A VTA notes the obvious, external condition of a tree and takes into account the condition of the root flare, the main trunk and the canopy. Tree Inventory Renton Dental Arts May 1, 2017 Kyle Henegar, Certified Arborist PN6445A Page 3 of 10 Observations I documented 15 trees at this location during my site visit including 3 trees onsite and 12 trees in the conservation easement. They are as follows: Tree Matrix: 11416 98th Ave NE, Renton, WA Tree # Botanical Name Common Name DBH RDL Structure Vigor Risk of Failure Comments Preservation Value 1 Pinus spp. Shore pine 10.5 20 Fair Good Low On property/2 needle pine/co-dom stems/ To be removed. Mod 2 Cedrus atlantica Atlas cedar 19 26 Good Fair Low On property / buried trunk flare/ To be removed. Mod 3 Pinus spp. Shore pine 24 26 Fair Fair Low On property / Co-dom stems at 12’/ To be removed. Mod 4 Pseudotsuga menziesii Douglas fir 20.5 28 Good Fair Low Conservation easement High 5 Pseudotsuga menziesii Douglas fir 18 26 Good Fair Low Conservation easement High 6 Sorbus acucuparia Mountain-ash 24 32 Fair Fair Mod Conservation easement/ To be removed. Low 7 Pseudotsuga menziesii Douglas fir 15 16 Good Fair Low Conservation easement High 8 Pseudotsuga menziesii Douglas fir 16.25 20 Good Fair Low Conservation easement High 9 Pseudotsuga menziesii Douglas fir 20.25 28 Good Fair Low Conservation easement High 10 Pseudotsuga menziesii Douglas fir 15 20 Good Fair Low Conservation easement High 11 Pseudotsuga menziesii Douglas fir 14.25 16 Good Fair Low Conservation easement High 12 Pseudotsuga menziesii Douglas fir 18.75 36 Good Fair Low Conservation easement High 13 Pseudotsuga menziesii Douglas fir 8 8 Fair Poor Low Conservation easement Mod 14 Pseudotsuga menziesii Douglas fir 18.5 36 Good Fair Low Conservation easement High 15 Acer mcacrophyllum Big leaf maple 36 40 Fair Good Low Conservation easement/ To be removed. Mod Discussion Each tree in this inventory is tagged with a numbered metal tag that corresponds to the tree matrix. The tags used in this inventory begin at #801 and end with #815 (#1-#15). The trees in this inventory are numbered on the attached site plan. I understand that the three trees onsite, trees #1-#3, will be removed to accommodate the new development project and that the developer has agreed to replant per the City of Renton Tree Retention/Land Clearing Plan. Through conversations with Mr. Ng, I understand that the development project may have an impact on trees #6, (the mountain ash) and tree #15 (the big leaf maple), both located in the conservation easement. The mountain ash is listed on the Washington State Noxious Weed list and the big leaf maple has fair structure for the species yet is considered a Landmark tree based on its size. Both of these trees are to be removed. Both trees may be candidates for replacement with evergreen species better suited to the site conditions and long term survivability. Suggestions for replacement include Thuja plicata or Western red cedar. Tree Inventory Renton Dental Arts May 1, 2017 Kyle Henegar, Certified Arborist PN6445A Page 4 of 10 Recommendations Tree Protection Measures In order for trees to survive the stresses placed upon them in the construction process, tree protection must be planned in advance of construction. If tree protection is not planned integral with the design and layout of the project, the trees will suffer needlessly and will possibly die. With proper preparation, often costing little or nothing extra to the project budget, trees can survive and thrive after construction. This is critical for tree survival because damage prevention is the single most effective treatment for trees on construction sites. Once trees are damaged, the treatment options available are limited. The following minimum Tree Protection Measures are included so that they can be copied and introduced into all relevant documents such as site plans, permit applications, conditions of approval and bid documents. These Tree Protection Measures are intended to be generic in nature. They will need to be adjusted to the specific circumstances of this site and the specific trees in question. Tree Protection Fences will need to be placed around each tree or group of trees to be retained at a distance of 1 foot for every 1 inch at Diameter at Breast Height (DBH). Tree Protection Fences are to be placed according to the attached drawing. Tree Protection Fences must be inspected prior to the beginning of any demolition or construction work activities. Nothing must be parked or stored within the Tree Protection Fences—no equipment, vehicles, soil, debris, or construction supplies of any sort. Cement trucks must not be allowed to deposit waste or wash out materials from drums within the Tree Protection Fences. The Tree Protection Fences need to be clearly marked with the following or similar text in 4 inches or larger letters: TREE PROTECTION FENCE DO NOT ENTER THIS AREA DO NOT PARK OR STORE MATERIALS WITHIN THE PROTECTION AREA Any questions, call Kyle Henegar, ISA Certified Arborist, 206-293-1270. The area within the Tree Protection Fencing must be covered with wood chips, hog fuel, or similar materials to a depth of 8 to 10 inches. The materials should be placed prior to beginning construction and remain until the Tree Protection Fencing is taken down. When excavation occurs near trees that are scheduled for retention, the following procedure must be followed to protect the long-term survivability of the tree: An International Society of Arboriculture (ISA) Certified Arborist must be working with all equipment operators. The Certified Arborist should be outfitted with a shovel, hand pruners, a pair of loppers, a handsaw, and a power saw (a Sawzall is recommended). The hoe must be placed to “comb” the material directly away from the trunk as opposed to cutting across the roots. Combing is the gradual excavation of the groundcover plants and soil in depths that extend only as deep as the tines of the hoe. When any roots of 1 inch diameter or greater of the tree to be retained are struck by the equipment, the Certified Arborist should stop the equipment operator. The Certified Arborist should then excavate around the tree root by hand/shovel and cleanly cut the tree root. After this is complete, the Certified Arborist should instruct the equipment operator to continue. Tree Inventory Renton Dental Arts May 1, 2017 Kyle Henegar, Certified Arborist PN6445A Page 5 of 10 Putting Utilities Under the Root Zone: Boring under the root systems of trees (and other vegetation) shall be done under the supervision of an ISA Certified Arborist. This is to be accomplished by excavating a limited trench or pit on each side of the critical root zone of the tree and then hand digging or pushing the pipe through the soil under the tree. The closest pit walls shall be a minimum of 7 feet from the center of the tree and shall be sufficient depth to lay the pipe at the grade as shown on the plan and profile. Tunneling under the roots of trees shall be done under the supervision of an ISA Certified Arborist in an open trench by carefully excavating and hand digging around areas where large roots are exposed. No roots 1 inch in diameter or larger shall be cut. The contractor shall verify the vertical and horizontal location of existing utilities to avoid conflicts and maintain minimum clearances; adjustment shall be made to the grade of the new utility as required. Watering: The trees will require significant watering throughout the summer and early fall in order to survive long- term. Easy and economical watering can be accomplished using soaker hoses placed three feet from the trunk of the tree and spiraled around the tree. One 75-foot soaker hose per tree is adequate. It is best to place the soakers using landscape staples, then cover the area with two to three inches composed materials. The composted material will act as a mulch to minimize evaporation and will also stimulate the microbial activity of the soil, which is another benefit to the health of the tree. Water the tree to a depth of 18 to 20 inches. I recommended leaving the water on the soaker hoses for six to eight hours and then digging down to determine how deep your water is penetrating. Then adjust accordingly. It may take a good two days of watering to reach the proper depth. Once the water reaches the proper depth, turn off the hoses for four weeks and then water again. Water more often when temperatures increase—every three weeks when temperatures exceed 80 degrees and every two weeks when temperatures exceed 90 degrees. Drying out the soil between watering is important to prevent soil pathogens from attacking the trees. 8. Pruning: All pruning should be done using ANSI A300 standards, using best management practices (http://tcia.org/business/ansi-a300-standards/part-1). When pruning trees, it is important to make final cuts at the proper location. Cuts should be made from just outside the branch bark ridge (readily visible on most species), to just outside the swollen base or branch collar. A clean, careful cut will remove the select branch but will not cut or injure the main trunk. Leaving stubs will lead to unwanted sprouting and decay of the remaining stem tissue. Cuts made too close (flush cuts) leave much larger wounds than proper cuts and can cause dieback of the surrounding cambium. As a result, flush cut wounds do not heal properly, causing major damage to the trunk from which the tree may not recover. Avoid having to prune branches that are over 1 to 2 inches in diameter. Tree Inventory Renton Dental Arts May 1, 2017 Kyle Henegar, Certified Arborist PN6445A Page 6 of 10 Tree Protection Fence Detail Glossary Canopy/crown: Upper part of a tree bearing foliage, limbs, and branches, measured from the lowest branch including all branches and foliage. Co-dominant Stem: A structurally unstable branch union often associated with a high risk of failure. A term used to describe two or more main stems (or "leaders") that are about the same diameter and emerge from the same location on the main trunk. Critical Root Zone: The area surrounding a tree at a distance from the trunk, which is equal to one (1) foot for every inch of trunk diameter measured at 4.5 feet from grade or otherwise determined by a qualified professional (example: one (1) foot radius per one (1) inch DBH). Diameter at Breast Height: A standard measurement of a tree most often taken at 4.5 feet from the base of the tree; however, this can vary depending if the tree has multiple trunks or is growing on a slope. Preservation Value Explanation  LOW = Poor specimen MODERATE = Common species with minimal character. HIGH = Good character tree, save if possible. SPECIAL = Unique species, save if possible. Radial Dripline: The distance from the tree trunk, that is equal to the furthest extent of the tree’s crown/canopy. Tree Protection Area: A designated area around trees where maximum protection and preservation efforts are implemented to minimize soil compaction, mechanical damage or other possible intrusions or insults into the critical Tree Inventory Renton Dental Arts May 1, 2017 Kyle Henegar, Certified Arborist PN6445A Page 7 of 10 root zone, which is equal to one (1) foot for every inch of trunk diameter measured at 4.5 feet from grade or otherwise determined by a qualified professional (example: one (1) foot radius per one (1) inch DBH). Trunk Flare: Transition zone from trunk to roots where the trunk expands into the buttress or structural roots. Visual Tree Assessment: Visual Tree Assessment is defined as the fastest but least thorough means of tree assessment. The assessor performs a visual tree assessment looking for obvious defects such as dead trees, large cavity openings, large dead or broken branches, fungal fruiting structures, large cracks, severe leans or limited soil volume. A basic method of evaluating structural defects and stability in trees. Certification of Performance I, Kyle Henegar, certify: I have personally inspected the trees on this property referred to in this report and that I have stated my findings accurately. I have no interest in the plant material or the property that is subject to this report and that I have no personal bias with respect to the parties involved. The opinions and conclusions stated are my own. My compensation is not contingent upon the reporting of a predetermined conclusion that favors the cause of the client or any other party. My opinions and conclusions were developed and this report has been prepared according to commonly accepted arboricultural practices. No one provided significant professional assistance. I am a member of the International Society of Arboriculture, the American Society of Consulting Arborists and Tree Risk Assessment Qualified. Tree Inventory Renton Dental Arts May 1, 2017 Kyle Henegar, Certified Arborist PN6445A Page 8 of 10 Waiver Of Liability There are many conditions affecting a tree’s health and stability which may be present but cannot be ascertained such as root rot, previous or unexposed construction damage, internal cracks, stem rot and more. Changes in circumstances and conditions can also cause a rapid deterioration of a tree’s health and stability. Adverse weather conditions can dramatically affect the health and safety of a tree in a very short amount of time. While I have used every reasonable means to examine this plant, this evaluation represents my opinion of the tree health at this point in time. These findings do not guarantee future safety nor are they predictions of future events. The tree evaluation consists of an external visual inspection of an individual tree’s root flare, trunk, and canopy from the ground only, unless otherwise specified. The inspection may also consist of taking trunk or root soundings for sound comparisons to aid the evaluator in determining the possible extent of decay within a tree. Soundings are only an aid to the evaluation process and do not replace the use of other more sophisticated diagnostic tools for determining the extent of decay within a tree. As conditions change, it is the responsibility of the property owners to schedule additional site visits by the ISA Certified Arborist. It is the responsibility of the property owner to obtain all required permits from city, county, state, or federal agencies. It is the responsibility of the property owner to comply with all applicable laws, regulations, and permit conditions. If there is a homeowners association, it is the responsibility of the property owner to comply with all Codes, Covenants, and Restrictions (CC&R’s) that apply to tree pruning and tree removal. This tree evaluation is to be used to inform and guide the client in the management of their trees. This in no way implies that the evaluator is responsible for performing recommended actions or using other methods or tools to further determine the extent of internal tree problems without written authorization from the client. Furthermore, the evaluator in no way holds that the opinions and recommendations are the only actions required to insure that the tree will not fail. A second opinion is recommended. The client shall hold the evaluator harmless for any and all injuries or damages incurred if the evaluator’s recommendations are not followed or for acts of nature beyond the evaluator’s reasonable expectations, such as severe winds, excessive rains, heavy snow loads, etc. This report and all attachments, enclosures, and references, are confidential and are for the use of the client concerned. They may not be reproduced, used in any way, or disseminated in any form without the prior consent of the client concerned and ISA Certified Arborist Kyle Henegar. Thank you for allowing me to be of service. Please contact me with any questions or concerns. Sincerely, Kyle Henegar 206-293-1270 ISA Certified Arborist PN6445A Tree Risk Assessment Qualified Member, American Society of Consulting Arborists Tree Inventory Renton Dental Arts May 1, 2017 Kyle Henegar, Certified Arborist PN6445A Page 9 of 10 Appendix A: Photos Photo 1. Shows view of tree #1, a shore pine with co-dominant stems. This tree is slated for removal as part of the development project. Photo 2. Shows view of tree #2, an Atlas cedar with buried trunk flare. This tree is slated for removal as part of the development project. Photo 3. Shows view of tree #3, a shore pine with co-dominant stems at 12 feet. This tree is slated for removal as part of the development project. Photo 4. Shows view of conservation easement looking north, northwest towards development project. Photos, continued Photo 5. Shows view of conservation easement looking east from subject property. Trees #6 and #15 may be candidates for removal and replacement with trees better suited to the site conditions with long term survivability. Replacement trees include Thuja plicata or Western red cedar.