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016 Tree Evaluation Report, Greenline Building B, 6-26-2018 EVALUATION OF INTERIOR TREES at the GREENLINE BUILDING B SITE Weyerhaeuser Way South Federal Way, WA 98003 File #17-104236-UP & 17-104237-SE Revised June 26, 2018 September 6, 2017 PREPARED FOR: Federal Way Campus, LLC Attn: Tom Messmer 11100 Santa Monica Boulevard Los Angeles, CA 90025 PREPARED BY: GILLES CONSULTING Brian K. Gilles, Consulting Arborist ISA Certified Arborist # PN-0260A ASCA Registered Consulting Arborist # RCA-418 ISA TRAQ Qualified ISA TRAQ Certified Instructor Evaluation of Trees at the Greenline Building B Site Weyerhaeuser Way South, Federal Way, WA 98003 Gilles Consulting June 26, 2018 Page 2 of 17 CONTENTS ASSIGNMENT .................................................................................................................. 3 SCOPE AND METHODOLOGY ................................................................................... 3 Evaluation of Trees & Status Determination .................................................................. 3 Additional Testing .......................................................................................................... 4 Failure ............................................................................................................................. 4 OBSERVATIONS ............................................................................................................. 4 Tall Trees Observed: ....................................................................................................... 4 Small Native Trees/Small Shrubs Observed ................................................................... 4 Low Growing Native Shrubs and Ground Covers Observed: ........................................ 5 Invasive Species Observed: ............................................................................................ 5 Tree Data ......................................................................................................................... 5 DISCUSSION .................................................................................................................... 5 Required Tree Retention ................................................................................................. 5 Minimum Tree Density Calculations .............................................................................. 6 Tree Protection Measures ............................................................................................... 7 WAIVER OF LIABILITY ............................................................................................... 7 ATTACHMENTS ............................................................................................................. 9 Evaluation of Trees at the Greenline Building B Site Weyerhaeuser Way South, Federal Way, WA 98003 Gilles Consulting June 26, 2018 Page 3 of 17 ASSIGNMENT Tom Messmer, of the Federal Way Campus LLC, contracted with Gilles Consulting to develop this report of the trees at the Greenline Building B Site on Weyerhaeuser Way South. In compliance with the Weyerhaeuser Company Concomitant Pre-Annexation Developer Agreement (Agreement), dated August 23, 1994, between the Weyerhaeuser Company and the City of Federal Way, the 1994 definitions of “signi ficant trees” was utilized to measure and evaluate the condition of the trees in the interior portion of the property. Note: See Managed Forest Buffer Management Plan at the Greenline Building B Site, dated June 26, 2018 for a discussion of the Managed Forest Buffer (MFB) on-site. See Tree Data for 32 Acre Site, dated 26 June 2018 for a complete dataset of significant and non-significant trees on the Building B Site. SCOPE AND METHODOLOGY Evaluation of Trees & Status Determination First, an inventory of the existing vegetation of the property was conducted. This included documenting the species present, their relative size, and their condition. Each tree was tagged with a unique number and its trunk measured at 4.5 feet above the average ground level to determine diameter, (DBH). Following the 1994 Federal Way City Code (FWCC) Section 22-1568(c)(6), we used the definition of a significant tree to determine the status of each tree encountered. As defined in 1994 FWCC Sec. 22-1568(b) “a Significant Tree is a tree that is: 1) Twelve inches in diameter or 37 inches in circumference measured four and one- half feet above the ground; and 2) In good health; and 3) Not detrimental to the community (e.g. is not diseased, dying, or likely of falling into public open space or right-of-way, etc.) or obscuring safe sight distance requirements. Significant trees shall not include red alder, cottonwood, poplar or big leaf maple.” Using 1994 FWCC Section 1568(c) Standards, calculations for significant tree retention were calculated and a Tree Retention Plan has been included in the permit documents but not as a part of the MFB Plan. This is because all of the trees in the MFB are to be retained—unless they pose a threat to life and property. These retained trees shall be protected as defined in the Tree Protection Measures section below. Trees were also evaluated for risk to determine whether or not any of the trees proposed for retention pose an unacceptable level of risk to life and property. The goal was to identify any potential hazard trees and manage them down to a safe level during clearing and grading phases of the project. We followed the protocol of the International Society Evaluation of Trees at the Greenline Building B Site Weyerhaeuser Way South, Federal Way, WA 98003 Gilles Consulting June 26, 2018 Page 4 of 17 of Arboriculture known as Tree Risk Assessment Qualification, TRAQ. This is a scientifically based process that includes a roots to shoots evaluation of each tree to determine health, structural stability, and likelihood of failure. Trees were then rated as Significant or Non-Significant based upon criteria a – c above and the size of their trunk at 4.5 feet as measured with a diameter tape measure. Additional Testing The trees all presented signs and/or symptoms that were readily discernible using the visual tree evaluation system of a Level II risk assessment. These signs and/or symptoms indicate extensive internal decay and/or structural defects in some trees and solid trunks and lack of disease in others. Therefore, no additional tests were performed during this site visit. Failure While no one can predict with absolute certainty which trees will or will not fail, we can, by using this scientific process, assess which trees are most likely to fail and take appropriate action to minimize injury and damage. OBSERVATIONS Tall Trees Observed:  Big Leaf Maple, Acer macrophyllum  Cascara, Rhamnus purshiana  Douglas Fir, Pseudotsuga menziesii  Oregon Ash, Fraxinus latifolia  Pacific Madrone, Arbutus menziesii  Pacific Willow, Salix lasiandra  Paperbark Birch, Betula papyrifera  Red Alder, Alnus rubra  Western Hemlock, Tsuga heterophylla  Western Red Cedar, Thuja plicata  The trees were rated on a scale from Dead, to Dying, to Poor, to Fair, to Good, to Very Good, to Excellent. The shrub and ground cover layers consisted of plants typical of lowland Puget Sound that include: Small Native Trees/Small Shrubs Observed  Vine Maple, Acer circinatum  Western Hazelnut, Corylus cornuta  Indian Plum, Oemleria cerasiformis  They are all in Fair to Excellent Condition. Evaluation of Trees at the Greenline Building B Site Weyerhaeuser Way South, Federal Way, WA 98003 Gilles Consulting June 26, 2018 Page 5 of 17 Low Growing Native Shrubs and Ground Covers Observed:  Salal, Gaultheria shallon  Trailing Blackberry, Rubus ursinus  Snowberry, Symphoricarpos albus  Oregon Grape, Mahonia nervosa  Bracken Fern, Pteridium aquilinum  They are all in Fair to Very Good Condition. Invasive Species Observed:  Himalayan Blackberry, Rubus discolor  English Ivy, Hedera helix  English Holly, Ilex aquifolium.  While small in number they appear healthy at this time.  Data for Greenline Building B: Building B Significant Trees (Interior) 527 Significant Trees (MFB) 80 TOTAL 607 o A complete data set of all trees identified within both the Greenline Building A and B projects can be found in the Tree Data for 32 Acre Site dated 26 June 2018. o There are a total of 527 significant trees in the interior of the Greenline Building B site. Tree Data See Tree Data for 32 Acre Site, dated 26 June 2018, for a complete dataset of evaluated significant trees on the property. DISCUSSION Required Tree Retention Retention of course, needs to take into account the location of the trees and the location of the proposed improvements. However, strongly advocate retaining as many more trees as possible over the minimum required if development allows. This affords significant flexibility during construction when unforeseen circumstances and events require the removal of trees that were at first planned for retention. If there is a bank of extra Evaluation of Trees at the Greenline Building B Site Weyerhaeuser Way South, Federal Way, WA 98003 Gilles Consulting June 26, 2018 Page 6 of 17 Significant Trees somewhere else on the property they can be switched out with a tree or more that needs to be removed unexpectedly. Minimum Tree Density Calculations The 1994 FWCC Tree Code requires that each project have a minimum density of at least 25% of the Significant Trees retained. Acreages for project area can be found in Attachment 1, Exhibits, Arborist Site Map. 32-acre Site (INTERIOR) 1245 significant trees/ 27.86 ac = 45 significant trees/ac (INTERIOR) *1427 TOTAL SIGNIFICANT TREES ON-SITE (INTERIOR + MFB) 1572F (Building B) Project Limits B MFB 2.51 ac Project Limits B INTERIOR 11.79 ac Project Limits B TOTAL 14.3 ac Total Significant Trees B Total Significant Trees B MFB 80 Total Significant Trees B INTERIOR 45 x11.79 ac= 527 607 Preserved Area B 2.17 ac Tree Preservation B 45 x2.17 ac= 97 Total Significant Trees Preserved B Tree Retention B 607 x25% 152 Total Significant Trees B MFB 80 Tree Preservation B 97 177 % Tree Retention 177/607= 0.292 OR 29.2% Replacement Trees B 152-177= -25 Evaluation of Trees at the Greenline Building B Site Weyerhaeuser Way South, Federal Way, WA 98003 Gilles Consulting June 26, 2018 Page 7 of 17 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 equipment arrival on site. If tree protection is not planned integral with the design and layout of the project, the trees will suffer needlessly and 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 minimum Tree Protection Measures in Attachment 2, Tree Protection Measures are on three separate sheets that can be copied and introduced into all relevant documents such as site plans, permit applications and conditions of approval, and bid documents so that everyone involved is aware of the requirements. These Tree Protection Measures are intended to be generic in nature. They will need to be adjusted to the specific circumstances of your site that takes into account the location of improvements and the locations of the trees. WAIVER OF LIABILITY There are many conditions affecting a tree’s health and stability, which may be present and cannot be ascertained, such as, root rot, previous or unexposed construction damage, internal cracks, stem rot and more which may be hidden. 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 these trees, 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 necessary professionals to ensure that the long-term success of the project is ensured. 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 Evaluation of Trees at the Greenline Building B Site Weyerhaeuser Way South, Federal Way, WA 98003 Gilles Consulting June 26, 2018 Page 8 of 17 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 Gilles Consulting. Thank you for calling Gilles Consulting for your arboricultural needs. Sincerely, Brian K. Gilles, Consulting Arborist ISA Certified Arborist # PN-0260A ASCA Registered Consulting Arborist # RCA-418 ISA TRAQ Qualified ISA TRAQ Certified Instructor Evaluation of Trees at the Greenline Building B Site Weyerhaeuser Way South, Federal Way, WA 98003 Gilles Consulting June 26, 2018 Page 9 of 17 ATTACHMENTS ATTACHMENT 1 - EXHIBITS .................................................................................... 10 ATTACHMENT 2 - TREE PROTECTION MEASURES ......................................... 11 ATTACHMENT 3 - BIBLIOGRAPHY........................................................................ 17 Evaluation of Trees at the Greenline Building B Site Weyerhaeuser Way South, Federal Way, WA 98003 Gilles Consulting June 26, 2018 Page 10 of 17 ATTACHMENT 1 - EXHIBITS Evaluation of Trees at the Greenline Building B Site Weyerhaeuser Way South, Federal Way, WA 98003 Gilles Consulting June 26, 2018 Page 11 of 17 ATTACHMENT 2 - 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 equipment arrival on site. 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 on three separate sheets so that they can be copied and introduced into all relevant documents such as site plans, permit applications and conditions of approval, and bid documents so that everyone involved is aware of the requirements. These Tree Protection Measures are intended to be generic in nature. They will need to be adjusted to the specific circumstances of your site that takes into account the location of improvements and the locations of the trees. Evaluation of Trees at the Greenline Building B Site Weyerhaeuser Way South, Federal Way, WA 98003 Gilles Consulting June 26, 2018 Page 12 of 17 TREE PROTECTION MEASURES 1. Tree Protection Fencing: a. Tree Protection Fences will need to be placed around each tree or group of trees to be retained. i. Tree Protection Fences are to be placed according to the approved limits of clearing. ii. The area inside the fences is the Tree Protection Zone. iii. The area outside the fences is the work zone or the construction zone. iv. Tree Protection Fences must be inspected prior to the beginning of any clearing, grading, or construction work activities. v. Nothing must be parked or stored within the Tree Protection Fences—no equipment, vehicles, soil, debris, or construction supplies of any sorts. b. Signs: i. The Tree Protection Fences need to be clearly marked with the following or similar text in four inch or larger letters: “TREE PROTECTION FENCE DO NOT ENTER THIS AREA DO NOT PARK OR STORE MATERIALS WITHIN THE PROTECTION AREA Any questions or concerns, call Brian K. Gilles at Gilles Consulting @ 425-417-0850” 2. Cement Trucks: a. Cement trucks must not be allowed to deposit waste or wash out materials from their trucks within the Tree Protection Fences. 3. Canopy Pruning: a. The canopies of the edge trees may need to properly pruned to allow building and construction clearance. b. The pruning must be done by an International Society of Arboriculture, (ISA) Certified Arborist using current industry standard pruning techniques. (ANSI A300 Pruning Standards and ANSI Z131.1 Safety Standards as well as all OSHA, WISHA, and local standards must be followed.) c. The pruning must be done from a lift truck to allow tip pruning and he smallest cuts possible or by using clean climbing techniques. Evaluation of Trees at the Greenline Building B Site Weyerhaeuser Way South, Federal Way, WA 98003 Gilles Consulting June 26, 2018 Page 13 of 17 d. Plant debris can be chipped and utilized on site for the mulch under the preserved/retained trees. 4. Excavation: a. When excavation occurs within the driplines of trees that are scheduled for retention, the following procedure must be followed to protect the long term survivability of the tree: b. An International Society of Arboriculture, (ISA) Certified Arborist must be working with all equipment operators. i. The Certified Arborist should be outfitted with a shovel, hand pruners, a pair of loppers, a handsaw, and a power saw (a “sawsall” is recommended). ii. The arborist must also have an air spade and compressor to blow the soil away and expose the roots for proper root pruning. c. The Hoe: i. The hoe used at first must be a small landscape sized hoe with a thumb attachment. ii. The hoe must be placed to gently lift and break the sidewalk and pull pieces of sidewalk away from the trunks. iii. The disposal trucks must be placed in the parking lot to receive the debris. iv. A larger hoe can be utilized in the parking lot to break up the sidewalk into small enough pieces to be efficiently loaded into the trucks and hauled away. 1. The hoes are not allowed to break up the sidewalk on unbroken sidewalk or over the tree roots within the canopy/driplines of the trees. d. The small hoe can then excavate down to its limits of depth. e. The larger hoe can then take over the excavation to the proper depth and of the rest of the site. 5. Tree Protection Fences will need to be placed around each tree or group of trees to be retained. a. Tree Protection Fences are to be placed according to the attached drawing at a distance of not less than 5 feet outside the dripline of the tree or group of trees to be saved. b. Tree Protection Fences must be inspected prior to the beginning of any demolition or construction work activities. c. Nothing must be parked or stored within the Tree Protection Fences—no equipment, vehicles, soil, debris, or construction supplies of any sorts. 6. Cement trucks must not be allowed to deposit waste or wash out materials from their trucks within the Tree Protection Fences. Evaluation of Trees at the Greenline Building B Site Weyerhaeuser Way South, Federal Way, WA 98003 Gilles Consulting June 26, 2018 Page 14 of 17 7. The Tree Protection Fences need to be clearly marked with the following or similar text in four inch or larger letters: “TREE PROTECTION FENCE DO NOT ENTER THIS AREA DO NOT PARK OR STORE MATERIALS WITHIN THE PROTECTION AREA Any questions or concerns, call Brian K. Gilles at Gilles Consulting @ 425-417-0850” 8. 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: a. An International Society of Arboriculture, (ISA) Certified Arborist must be working with all equipment operators. i. The Certified Arborist should be outfitted with a shovel, hand pruners, a pair of loppers, a handsaw, and a power saw (a “sawsall” type reciprocating saw is recommended). b. The hoe must be placed to “comb” the material directly away from the trunk as opposed to cutting across the roots. i. Combing is the gradual excavation of the ground cover plants and soil in depths that only extend as deep as the tines of the hoe. c. When any roots of one inch diameter or greater, of the tree to be retained, is struck by the equipment, the Certified Arborist should stop the equipment operator. d. The Certified Arborist should then excavate around the tree root by hand/shovel and cleanly cut the tree root. i. The Certified Arborist should then instruct the equipment operator to continue. 9. Putting Utilities Under the Root Zone: a. If it is necessary to place utilities within the dripline, it must be accomplished with trenchless technology such as boring under the root systems of trees (and other vegetation). This work shall be done under the supervision of an ISA Certified Arborist. b. 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. Evaluation of Trees at the Greenline Building B Site Weyerhaeuser Way South, Federal Way, WA 98003 Gilles Consulting June 26, 2018 Page 15 of 17 c. 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. d. 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. Evaluation of Trees at the Greenline Building B Site Weyerhaeuser Way South, Federal Way, WA 98003 Gilles Consulting June 26, 2018 Page 16 of 17 Evaluation of Trees at the Greenline Building B Site Weyerhaeuser Way South, Federal Way, WA 98003 Gilles Consulting June 26, 2018 Page 17 of 17 ATTACHMENT 3 - BIBLIOGRAPHY 1. Dirr, Michael A. Manual of Woody Landscape Plants, Their Identification, Ornamental Characteristics, Culture, Propagation, and Uses. Champaign: Stipes Publishing Company, 1990. 2. Dunster, Dr. Julian A., R.P.F., M.C.I.P. Documenting Evidence, Practical Guidance for Arborists, First Choice Books, Victoria, BC, Canada. 2014. 3. Eric Allen, et al. Common Tree Diseases of British Columbia. Victoria: Canadian Forest Service, 1996. 4. Goheen, Ellen Michaels and Elizabeth A Willhite, Field Guide to the Common Diseases and Insect Pests of Oregon and Washington Conifers, R6-NR-FID-PR-01-06.2006. USDA Forest Service, Pacific Northwest Region. 5. Harris, Richard W, James Clark, and Nelda Matheny. Arboriculture, Integrated Management of Landscape Trees, Shrubs, and Vines. 4th ed. Upper Saddle River: Prentice Hall, 2004. 6. Link, Russell, Landscaping for Wildlife in the Pacific Northwest, The University of Washington Press, Seattle, WA. 1999. 7. Matheny, Nelda P. and Clark, James R. Evaluation of Hazard Trees. 2nd ed. Savoy: The International Society of Arboriculture Press, 1994. 8. Matheny, Nelda P. and Clark, James R. Trees & Development, A Technical Guide to Preservation of Trees During Land Development. Savoy: The International Society of Arboriculture Press, 1998. 9. Mathews, Daniel. Cascade -- Olympic Natural History. Portland, Oregon: Raven Editions with the Portland Audubon Society, 1992. 10. Mattheck, Claus and Breloer, Helge. The Body Language of Trees, A Handbook for Failure Analysis. London: HMSO, 1994. 11. Pacific Northwest Chapter-ISA. Tree Risk Assessment in Urban Areas and the Urban/Rural Interface. Course Manual. Release 1.5. PNW-ISA: Silverton, Oregon, 2011. 12. Petrides, George A. and Wehr, Janet. A Field Guide to Eastern Trees, Eastern United States and Canada including the Midwest. New York: Houghton Mifflin Company, 1998. 13. Scharpf, Robert F. Diseases of Pacific Coast Conifers. Albany, California: USDA Forest Service, Agriculture Handbook 521, rev. June 1993. 14. Sinclair, Wayne A., Lyon, Howard H., and Johnson, Warren T. Diseases of Trees and Shrubs. Ithaca, New York: Cornell University Press, 1987. 15. Smiley, E. Thomas, Nelda Matheny, and Sharon Lilly, Tree Risk Assessment Best Management Practices, ANSI A300 Part 9: Tree, Shrub, and Other Woody Plant Management —Standard Practices (Tree Risk Assessment a. Tree Structure Assessment). The International Society of Arboriculture Press. Champaign. IL. 2011. 16. Watson, Gary W., and Neely, Dan, eds. Trees & Building Sites. Savoy: The International Society of Arboriculture Press, 1995.