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24-100051-SU-CN Bilovol Short Plat TPP 01.29.2024 WASHINGTON FORESTRY CONSULTANTS, INC. FORESTRY AND VEGETATION MANAGEMENT SPECIALISTS W F C I O: 360/943-1723 C: 360/561-4407 9136 Yelm Hwy SE Olympia, WA 98513 URBAN/RURAL FORESTRY • TREE APPRAISAL • TREE RISK ASSESSMENT RIGHT-OF-WAYS • VEGETATION MANAGEMENT • FOREST/TREE MGT. PLANS • EXPERT TESTIMONY Member of International Society of Arboriculture and Society of American Foresters - Preliminary Tree Conservation Plan - BILOVOL SHORT PLAT 6th Avenue SW & SW 366th Street Federal Way, WA Prepared for: Mike Bilovol, Owner Prepared by: Washington Forestry Consultants, Inc. Date of Report: September 17, 2023 Introduction The project proponent is planning to short plat a 0.74-acre parcel at the corner of 6th Avenue SW and SW 366th Street in Federal Way, Washington. The proponent has retained WFCI to: • Complete and inventory and assessment of the trees on the site. • Make recommendations for retention, removal, protection, and/or cultural care. • Complete tree retention and replacement calculations according to Federal Way Municipal Code 19.120.130. • Prepare a tree protection plan. Observations Methodology WFCI has evaluated all trees ≥6 inches diameter at breast height (DBH) in the proposed project area and assessed their potential to be incorporated into the new project. The tree evaluation phase used methodology developed by Matheny and Clark (1998) in their text Trees and Development: A Technical Guide to Preservation of Trees During Land Development, published by the International Society of Arboriculture, Champaign, IL 1998. In all cases, the overall health of the tree was considered relative to its ability to add value to the new project. The potential for incorporation into the project design has been evaluated as well. Trees that are preserved near new construction must be carefully selected to make sure that they Bilovol Short Plat –Tree Conservation Plan Washington Forestry Consultants, Inc. Page 2 can survive construction impacts, adapt to a new environment and perform well in the landscape. Healthy, vigorous trees are better able to tolerate impacts such as root injury, changes in soils moisture regimes, and soil compaction than are low vigor trees. Structural characteristics are also important in assessing suitability. Trees with significant decay and other structural defects that cannot be treated are likely to fail. Such trees should not be preserved in areas where damage to people or property could occur. Site Description The project area includes one 0.74-acre parcel. The parcel number is 3021049155. There are no improvements on the site. The topography of the parcel is flat. The project area is bordered by single-family homes to the north and east, SW 366th Street to the south, and 6th Avenue SW to the west. Soil Depth and Productivity According to the Natural Resource Conservation Service Soil Survey the one soil type on the site. It is the Alderwood gravelly sandy loam, a moderately deep, moderately well drained soil found on glacial till plains. It is formed in ablation till overlying basal till. A weakly cemented hardpan is at a depth of 20 to 40 inches. Permeability is moderately rapid above the hardpan and very slow in the pan. Available water capacity is low. Effective rooting depth is 20-40 inches. A perched seasonal high-water table is at a depth of 18-36 inches from November to March. The potential for windthrow of trees is moderate under normal conditions. New trees require irrigation for establishment. In areas where grading brings the hardpan nearer to the surface, the hardpan must be fractured under new trees to provide soil volume for root development and to improve drainage around the tree. Bilovol Short Plat –Tree Conservation Plan Washington Forestry Consultants, Inc. Page 3 Figure 1. Soil Map of Bilovol Short Plat Site. AgB – Alderwood gravelly sandy loam Tree Conditions There is one forest cover type on the site for the purpose of description. Type I. – This forest type covers the entire parcel. The forest stand on the parcel is made up of large, native trees. Tree species includes bigleaf maple (Acer macrophyllum), bird cherry (Prunus avium), black cottonwood (Populus trichocarpa), Douglas-fir (Pseudotsuga menziesii), and Pacific madrone (Arbutus menziesii). Our inventory found 35 trees on-site. Eighty-three percent of the trees are in ‘Fair’ or better condition. The diameter range for the trees is from 8 to 45 inches DBH. A complete tree list is in Attachment 3. Trees in this type have been growing as a contiguous stand. Any trees to be retained in this type should be done in groups of as many trees as possible. The property lines were not marked in the field so a small number of borderline trees may have been missed during the inventory. Bilovol Short Plat –Tree Conservation Plan Washington Forestry Consultants, Inc. Page 4 Table 1. Summary of Trees in Cover Type I. Species DBH Range (in.) Condition Range # of Healthy Significant Trees # of Unhealthy Significant Trees Total # of Trees Bigleaf Maple 8 – 45 Very Poor – Good 3 3 6 Bird Cherry 9 Good 1 0 1 Black Cottonwood 32 – 35 Fair – Good 3 0 3 Douglas-fir 10 – 35 Very Poor – Good 16 1 17 Pacific Madrone 9 – 28 Dead – Good 6 2 8 Total 8 – 45 Dead - Good 29 6 35 The understory vegetation in the forested areas are dense with Indian plum (Oemleria cerasiformis), Oregon grape (Mahonia nervosa), sword fern (Polystichum munitum), baldhip rose (Rosa gymnocarpa), Himalayan black berry (Rubus armeniacus), English ivy (Hedera helix) and trailing blackberry (Rubus ursinus). Photo 1. View of typical trees on Bilovol Short Plat. Bilovol Short Plat –Tree Conservation Plan Washington Forestry Consultants, Inc. Page 5 Off-Site Impacts Tree removal and grading for this project may impact off-site trees north of the project area. There are multiple Douglas-fir and Pacific madrone trees that have roots and canopies that encroach onto the subject parcel. A tree risk assessment should be conducted on these trees after site clearing. The remaining three sides have been cleared of any trees on surrounding properties. Potential Tree Retention All healthy trees in the northern area of the lots have the potential to be retained. There are many Douglas-fir, Pacific madrone, and bigleaf maple in this area that will make good retention trees. A full grading plan is required to determine which trees can be saved. Tree Retention Calculations Federal Way municipal code 19.120.130 requires a minimum tree unit density of 25 tree units per acre for Single-family Residential zoned development. The following is a summary of the planned tree retention and removal: Total Project Acreage: 0.74 acres Minimum Density Requirement (25 tree units/acre x 0.74 acres): 18.5 tree units This site will require 18.5 tree units to be retained onsite to meet the City of Federal Way minimum density requirement. Once a grading plan is developed the planned tree retention can be calculated. Tree Protection Measures Trees to be saved must be protected during construction by a six-foot-high chain link fencing (Attachment 4), located 5 feet outside of the drip line of the trees. An existing fence surrounds much of the property – this should be adequate to protect these edges. Placards shall be placed on the fencing every 50 feet indicating the words, "NO TRESPASSING - Protected Trees". The individual RPZ are a radius of one foot for each one inch of DBH (6 feet minimum), unless otherwise delineated by WFCI. There should be no equipment activity (including rototilling) within the critical root zone. No irrigation lines, trenches, or other utilities should be installed within the CRZ. Cuts or fills should impact no more than 25% of a tree’s root system. If topsoil is added to the root zone of a protected tree, the depth should not exceed 2 inches of a sandy loam or loamy fine sand topsoil and should not cover more than 25% of the root system. Bilovol Short Plat –Tree Conservation Plan Washington Forestry Consultants, Inc. Page 6 If roots are encountered outside the RPZ during construction, they should be cut cleanly with a saw and covered immediately with moist soil. Noxious vegetation within the critical root zone should be removed by hand. If a proposed save-tree must be impacting by grading or fills, then the tree should be re-evaluated by WFCI to determine if the tree can be saved with mitigating measures, or if the tree should be removed. Pruning and Thinning All individual trees to be saved near or within developed areas should have their crowns raised to provide a minimum of 8 feet of ground clearance over sidewalks and landscape areas, 15 feet over parking lots or streets, and at least 10 feet of building clearance. All pruning should be done according to the ANSI A300 standards for proper pruning, and be completed by an International Society of Arboriculture Certified Arborist®, or be supervised by a Certified Arborist®. Conclusions and Timeline for Activity 1. The final, approved tree conservation plan map should be included in the construction drawings for bid and construction of the project and should be labeled as such. 2. Stake and heavily flag the clearing limits. 3. Contact WFCI to attend pre-job conference and discuss tree protection issues with contractors. WFCI can verify all trees to be saved and/or removed are adequately marked for retention. WFCI can inspect and mark any additional hazard trees or trees that will be impacted by grading, trenching or development for removal in the save tree areas. 4. Complete logging. Complete necessary hazard tree removals and invasive plant removals from the tree protection areas. No equipment should enter the tree protection areas during logging. WFCI should inspect the save trees after logging, to identify any trees that may have been damaged, or any other hazard trees. The logger can then remove these trees before they depart the site. 5. Install tree protection fences along the 'limits of construction'. The fences should be located at the limits of construction or 5 feet outside of the drip line of the save tree or as otherwise specified by WFCI. 6. Complete clearing of the project. Maintain fences throughout construction. 7. Do not excavate stumps within 10’ of trees to be saved. These should be individually evaluated by WFCI to determine the method of removal. 8. Complete all necessary pruning on save trees or stand edges to provide at least 8’ of ground clearance near sidewalks and trails, and 15’ above all driveways or access roads. 9. Complete grading and construction of the project. Bilovol Short Plat –Tree Conservation Plan Washington Forestry Consultants, Inc. Page 7 Summary Federal Way municipal code 19.120.130 requires a minimum tree unit density of 25 tree units per acre for net developable acreage on single-family zoned sites. The developable area of the site is 0.74-acres, requiring 18.5 tree units to be retained on-site. There are many quality, long- term trees located along the northern property line that can be retained. A grading plan is needed to calculate the planned tree retention. Please give us a call if you have any further questions. Respectfully submitted, Washington Forestry Consultants, Inc. Galen M. Wright, ACF, ASCA Joshua Sharpes ISA Bd. Certified Master Arborist PN-129BU Professional Forester Certified Forester No. 44 ISA Certified Arborist®, ISA Tree Risk Assessor Qualified Municipal Specialist, PN- 5939AM ASCA Tree and Plant Appraisal Qualified ISA Tree Risk Assessor Qualified Bilovol Short Plat –Tree Conservation Plan Washington Forestry Consultants, Inc. Page 8 Attachment 1. Aerial Photo of Bilovol Short Plat (King County iMap 2021) Approximate Project Boundary Healthy Tree Unhealthy Tree 1 7 19 21 31 33 2 3 4 5 6 8 9 10 11 12 13 14 15 16 17 18 20 22 23 24 25 26 27 28 29 30 32 33 34 Bilovol Short Plat –Tree Conservation Plan Washington Forestry Consultants, Inc. Page 9 Attachment 2. Bilovol Short Plat Site Plan Area of Potential Save Trees Bilovol Short Plat –Tree Conservation Plan Washington Forestry Consultants, Inc. Page 10 Attachment 3. Bilovol Short Plat Tree List Tree # Species DBH (in.) Condition Savable Based on Tree Condition Alone? Yes or No Minimum Root Protection Zone (feet) Tree Credits Comment 1 Douglas-fir 24 Very Poor No 14 2.5 large decay column in stem 2 Douglas-fir 27 Fair Yes 16 3 roots cut by wall 10' to east 3 Douglas-fir 33 Fair Yes 20 3 graded around roots 4 Douglas-fir 29 Fair Yes 17 3 roots cut by wall 7' to east 5 Bigleaf Maple 8 Fair Yes 6 1.5 6 Pacific Madrone 20 Fair Yes 12 2.5 7 Bigleaf Maple 22 Very Poor No 13 2.5 butt decay and Kretzschmaria deusta 8 Pacific Madrone 26 Good Yes 16 3 9 Pacific Madrone 28 Fair Yes 17 3 minor dieback 10 Douglas-fir 26 Good Yes 16 3 11 Douglas-fir 19 Fair Yes 11 2.5 12 Douglas-fir 19 Fair Yes 11 2.5 stem defect, ok 13 Douglas-fir 18 Good Yes 11 2 14 Bigleaf Maple 9,14,18 Good Yes 15 3 15 Douglas-fir 30 Good Yes 18 3 16 Bird Cherry 9 Good Yes 6 1.5 17 Pacific Madrone 12,13,15 Fair Yes 14 2.5 minor dieback 18 Bigleaf Maple 11 Good Yes 7 1.5 19 Bigleaf Maple 11 Poor No 7 1.5 topped for powerline 20 Black Cottonwood 32 Good Yes 19 3 21 Pacific Madrone 13 Dead No 8 2 22 Black Cottonwood 32 Good Yes 19 3 23 Douglas-fir 10 Good Yes 6 1.5 24 Douglas-fir 34 Good Yes 20 3 25 Black Cottonwood 35 Fair Yes 21 3 26 Douglas-fir 18 Fair Yes 11 2 27 Douglas-fir 26 Good Yes 16 3 28 Pacific Madrone 24 Good Yes 14 2.5 29 Douglas-fir 35 Good Yes 21 3 30 Douglas-fir 31 Good Yes 19 3 31 Bigleaf Maple 45 Very Poor No 27 3 major dieback, previous stem failure 32 Pacific Madrone 16 Fair Yes 10 2 Bilovol Short Plat –Tree Conservation Plan Washington Forestry Consultants, Inc. Page 11 Tree # Species DBH (in.) Condition Savable Based on Tree Condition Alone? Yes or No Minimum Root Protection Zone (feet) Tree Credits Comment 33 Pacific Madrone 9 Dead No 6 1.5 34 Douglas-fir 24,35 Fair Yes 26 3 co-dominant stems 35 Douglas-fir 9,10 Good Yes 8 2 Bilovol Short Plat –Tree Conservation Plan Washington Forestry Consultants, Inc. Page 12 Attachment 4. Tree Protection Fence Detail Temporary Chain Link on Driven Posts Bilovol Short Plat –Tree Conservation Plan Washington Forestry Consultants, Inc. Page 13 Attachment 5. Individual Tree Rating Key for Tree Condition RATING SYMBOL DEFINITION Very Good VG • Balanced crown that is characteristic of the species • Normal lateral and terminal branch growth rates for the species and soil type • Stem sound, normal bark vigor • No root problems • No insect or disease problems • Long-term, attractive tree Good G • Crown lacking symmetry but nearly balanced • Normal lateral and terminal branch growth rates for the species and soil type • Minor twig dieback O.K. • Stem sound, normal bark vigor • No root problems • No or minor insect or disease problems – insignificant • Long-term tree Fair F • Crown lacking symmetry due to branch loss • Slow lateral and terminal branch growth rates for the species and soil type • Minor and major twig dieback – starting to decline • Stem partly unsound, slow diameter growth and low bark vigor • Minor root problems • Minor insect or disease problems • Short-term tree 10-30 years Poor P • Major branch loss – unsymmetrical crown • Greatly reduced growth • Several structurally import dead or branch scaffold branches • Stem has bark loss and significant decay with poor bark vigor • Root damage • Insect or disease problems – remedy required • Short-term tree 1-10 years Very Poor VP • Lacking adequate live crown for survival and growth • Severe decline • Minor and major twig dieback • Stem unsound, bark sloughing, previous stem or large branch failures, very poor bark vigor • Severe root problems or disease • No or minor insect or disease problems • Mortality expected within the next few years Dead DEAD • Dead Bilovol Short Plat –Tree Conservation Plan Washington Forestry Consultants, Inc. Page 14 Attachment 6. Assumptions and Limiting Conditions 1) Any legal description provided to the Washington Forestry Consultants, Inc. is assumed to be correct. Any titles and ownership's to any property are assumed to be good and marketable. No responsibility is assumed for matters legal in character. Any and all property is appraised or evaluated as though free and clear, under responsible ownership and competent management. 2) It is assumed that any property is not in violation of any applicable codes, ordinances, statutes, or other governmental regulations, unless otherwise stated. 3) Care has been taken to obtain all information from reliable sources. All data has been verified insofar as possible; however, Washington Forestry Consultants, Inc. can neither guarantee nor be responsible for the accuracy of information. 4) Washington Forestry Consultants, Inc. shall not be required to give testimony or to attend court by reason of this report unless subsequent contractual arrangements are made, including payment of an additional fee for such services as described in the fee schedule and contract of engagement. 5) Loss or alteration of any part of this report invalidated the entire report. 6) Possession of this report or a copy thereof does not imply right of publication or use for any purpose by any other than the person to whom it is addressed, without the prior expressed written or verbal consent of Washington Forestry Consultants, Inc. 7) Neither all or any part of the contents of this report, nor copy thereof, shall be conveyed by anyone, including the client, to the public through advertising, public relations, news, sales or other media, without the prior expressed written or verbal consent of Washington Forestry Consultants, Inc. -- particularly as to value conclusions, identity of Washington Forestry Consultants, Inc., or any reference to any professional society or to any initialed designation conferred upon Washington Forestry Consultants, Inc. as stated in its qualifications. 8) This report and any values expressed herein represent the opinion of Washington Forestry Consultants, Inc., and the fee is in no way contingent upon the reporting of a specified value, a stipulated result, the occurrence neither of a subsequent event, nor upon any finding in to reported. 9) Sketches, diagrams, graphs, and photographs in this report, being intended as visual aids, are not necessarily to scale and should not be construed as engineering or architectural reports or surveys. 10) Unless expressed otherwise: 1) information contained in this report covers only those items that were examined and reflects the condition of those items at the time of inspection; and 2) the inspection is limited to visual examination of accessible items without dissection, excavation, probing, or coring. There is no warranty or guarantee, expressed or implied, that problems or deficiencies of the tree or other plant or property in question may not arise in the future. Note: Even healthy trees can fail under normal or storm conditions. The only way to eliminate all risk is to remove all trees within reach of all targets. Annual monitoring by an ISA Certified Arborist or Certified Forester will reduce the potential of tree failures. It is impossible to predict with certainty that a tree will stand or fail, or the timing of the failure. It is considered an ‘Act of God’ when a tree fails, unless it is directly felled or pushed over by man’s actions.