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HomeMy WebLinkAboutRS_Preliminary_Tree_Protection_Plan_230825_v1 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 Protection Plan- TALBOT ROAD PROJECT 2103 Talbot Road South Renton, WA 98055 Prepared for: Lili Lu / 吕莉莉 CEO Global Land LLC Prepared by: Washington Forestry Consultants, Inc. Date of Report: June 26, 2023 Introduction The project proponent is planning to construct a new 6-lot short plat on one parcel totaling 1.39- acres at 2103 Talbot Road South in Renton. The proponent has retained WFCI to: • Evaluate and inventory all trees on the site pursuant to the requirements of the City of Renton 4-4-130 Tree Retention and Land Clearing Regulations. • Make recommendations for retention of significant trees, along with required protection and cultural measures. Observations Methodology WFCI has evaluated all trees with a caliper of at least 6" diameter at breast height (DBH), except alder or cottonwood trees, which qualify as significant trees with a caliper of 8" or greater. To be a significant tree, it must have a condition rating of Fair or better. Trees rated as Poor, Very Poor, or Dead or are defective, diseased and/or in decline and are not long-term trees and are not considered to be significant trees. All off-site trees with driplines or root protection zones (RPZ’s) encroaching the site were assessed as well. Talbot Road Project – Preliminary Tree Protection Plan Washington Forestry Consultants, Inc. Page 2 The tree evaluation phase used methodology developed by Nelda Matheny and Dr. James Clark in their 1998 publication Trees and Development: A Technical Guide to Preservation of Trees during Land Development. Site Description The project site consists of one 1.39-acre parcel, # 7222000175. The cover type on the site is dominated by a grass pasture area in the southern half of the parcel. A single-family home and associated outbuildings are in the northern half. The topography moderately slopes to the west from the house area. The site has a westerly aspect. There are high voltage transmission powerlines that run along the west property line. The project is bordered by single-family homes to the north and south, Talbot Road S. to the east, and Shattuck Avenue S. to the west. Soils Description According to the USDA Natural Resource Conservation Service soil survey the soil type in the project area is the Beausite gravelly sandy loam, a moderately deep, well-drained soil. It is formed as glacial till over residuum from sandstone. Permeability is moderately high to high. Available water capacity is low. Lithic bedrock occurs at a depth of 24 to 40 inches. The effective rooting depth for trees is to the bedrock. The potential for windthrow of trees is slight under normal conditions. New trees require irrigation for establishment. Figure 1. Talbot Road Project Soils Map BeC – Beausite gravelly sandy loam Talbot Road Project – Preliminary Tree Protection Plan Washington Forestry Consultants, Inc. Page 3 Existing Tree Conditions There is one forest cover type on the project area for the purpose of description. The aerial photo of the project, with tree locations, is shown in Attachment 1. Type I. -- This cover type covers the entire project site. There are a total of 26 trees in the type. There are introduced trees planted around the home and naturally seeded native trees growing on the perimeters of the site. The size of significant trees ranges from 6 inches to 30 inches in diameter at breast height (DBH). Tree species include apple (Malus spp.), bigleaf maple (Acer macrophyllum), cherry (Prunus spp.), cypress (Cupressus spp.), flowering dogwood (Cornus florida), hawthorn (Crataegus monogyna), English holly (Ilex aquifolium), and Oregon ash (Fraxinus latifolia). Tree conditions on the site range from ‘Very Poor’ to ‘Good,’ with just over half the trees (54%) described as being in ‘Poor’ or worse condition. The high number of trees in poor condition is due to trees under the overhead powerlines that have been topped multiple times for clearance. The topping has created areas of decay in the tree’s upper canopies. The trees should be removed and the area re-planted with a small scale tree that will not need continual clearance pruning. Table 1. Summary of trees on Talbot Road Project Site. Species DBH Range (in.) Condition Range Total # of Trees # of Healthy Trees # of Unhealthy Trees* Species Composition of the Stand Apple 6 – 21 Very Poor - Good 6 4 2 23 Bigleaf Maple 15 – 25 Very Poor – Poor 3 0 3 12 Cherry 6 – 17 Poor – Good 4 1 3 15 Cypress 19 – 20 Good 2 2 0 8 Flowering Dogwood 8 Good 1 1 0 3 Hawthorn 6 – 14 Good 3 3 0 12 Holly 7 – 18 Poor – Good 2 1 1 8 Oregon Ash 6 – 30 Very Poor – Poor 5 0 5 19 Sum 6 - 30 Very Poor - Good 26 12 14 100% *Trees rated as dead, very poor, or poor. Twelve of the 26 significant trees could be potentially retained on this site when only tree health is considered. The remaining trees are in poor health or have been topped. One holly tree that has some top dieback but will be saved as part of the project. There are 3 Landmark sized trees on the project site. Only one of those trees is healthy and would make good long-term trees to save. The one healthy Landmark tree is proposed to be retained. Talbot Road Project – Preliminary Tree Protection Plan Washington Forestry Consultants, Inc. Page 4 The understory vegetation throughout the type is grass, weeds, and other planted shrubs in the landscape. Photo 1: View of trees 1 – 9 on the Talbot Road Project Site. Off-site Impacts There are no off-site trees that will be impacted from grading on the project. A few small landscape trees have branches that overhang the site. The branches can be pruned back to the property line without causing damage to the trees. Talbot Road Project – Preliminary Tree Protection Plan Washington Forestry Consultants, Inc. Page 5 Discussion Potential for Tree Retention There are four trees that have the potential to be retained with this site plan. All the trees are located on lot 6 around the existing home that will be saved as part of the project. The one healthy Landmark tree is being saved. The remaining trees are all under the footprints of improvements. Tree Density Calculations Title 4-4-130H(a) of the Renton Municipal Code (RMC) requires 30% of the significant trees on the site to be retained. There are a total of 26 significant sized trees on the parcel. After allowed tree deductions 16 trees remain for calculating the 30% requirement. A total of 5 significant trees will need to be retained in the project area to meet the requirement. Total # of Significant Trees: 26 Trees # of High Risk Significant Trees: 0 Trees # of Trees in the Public Rights-of-Ways: 10 Trees # of Significant Trees After Deductions: 16 Trees # of Significant Trees Required to be Saved (30% of 16 Trees): 5 Trees # of Significant Trees Planned to be Saved 4 Trees Shortfall of Significant Tree Requirement 1 Tree Additionally, RMC4-4-130H(b) requires a minimum tree credit density of 30 tree credits per acre of net developable acreage. The following is a summary of the projected tree density requirements: Gross Site Acreage: 1.39 Acres Designated Public Rights-of-way: 0.0 Acres Net Developable Acres: 1.39 Acres Required Tree Credit Density (1.39 Acres x 30 Credits/Acre): 42.0 Tree Credits Proposed Tree Retention: Developed Area (4 trees) 32.0 Tree Credits Shortfall of Tree Credit Requirement: 10.0 Tree Credits By retaining 4 of the significant trees on the site, this plan falls short of the minimum significant tree retention requirement by 1 tree. Required tree credit retention is less than the minimum tree Talbot Road Project – Preliminary Tree Protection Plan Washington Forestry Consultants, Inc. Page 6 credits by 10.0 credits. Additional trees will be required to be replanted to replace minimum shortfall. When the required number of protected trees cannot be retained, replacement trees, with at least a two-inch (2") caliper deciduous or an evergreen at least six feet (6') tall, shall be planted based on the tree credit value of each protected tree removed. A fee in lieu of tree planting, the cost of which can be determined by the City of Renton can also substitute for tree replacement if replanting on-site is not feasible. All reasonable efforts have been taken to preserve trees utilizing the highest priority possible. The retention of higher priority trees is not feasible or practical for the project site due to the required improvements along Shattuck Avenue. The trees in this area that form a continuous canopy are in poor condition from topping. The location of trees and the lot layout limits the number of trees that can be retained on this project. Recommendations Tree Protection Measures All save trees, including off-site edge trees, must be protected during construction by a temporary chain-link fence (Attachment 7). Placards shall be placed on the fencing every 50 feet indicating the words, "NO TRESPASSING - Protected Trees". The individual tree RPZ is the dripline (6 feet minimum), unless otherwise delineated by WFCI in the field and described in the attached tree list (Attachment 3). If approved, the silt-fence could double as the tree protection fence for select off-site trees. Tree protection fences should be placed around the edge of the root protection zone (RPZ). The fence should be erected after logging but prior to the start of clearing. The fences should be maintained until the start of the landscape installation. There should be no equipment activity (including rototilling) within the root protection zone. No irrigation lines, trenches, or other utilities should be installed within the RPZ. Cuts or fills should impact no more than 20% 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 20% of the root system. 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 root protection zone should be removed by hand. If a proposed save tree must be impacted by grading or fills more than allowed for by WFCI in the tree list, 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. Talbot Road Project – Preliminary Tree Protection Plan Washington Forestry Consultants, Inc. Page 7 Pruning and Thinning Pruning should be done to coincide with land clearing, to facilitate clean-up and while access to the trees is available (before houses are constructed). 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. Care will need to be taken to avoid trespassing when pruning offsite trees. This is best achieved by getting cooperation and permission from the tree owner. If no permission is obtained, then legally one cannot prune beyond the property line – ground to sky. 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. Four significant trees equaling 32.0 tree credits are proposed to be retained on the site. 2. The final, approved tree protection plan map should be included in the construction drawings for bid and construction of the project and should be labeled as such. 3. Stake and heavily flag the clearing limits. 4. 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. 5. Conduct 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. 6. Before land clearing is complete, do all necessary pruning on save trees and off-site trees to provided new home clearances. 7. Contact WFCI to inspect the tree tracts after logging, but prior to land clearing to identify any additional hazard trees that should be removed. 8. Install tree protection fences along the 'limits of construction'. The fences should be located at the limits of construction or at the dripline of the save tree or as otherwise specified by WFCI. Maintain fences throughout construction. 9. Complete clearing of the project. 10. Do not excavate stumps within 10’ of trees to be saved. These should be individually evaluated by WFCI to determine the method of removal. 11. Complete grading and construction of the project. 12. Contact WFCI to final inspect the tree protection areas after grading. 13. All save trees within reach of targets should be inspected annually for 2 years by a qualified professional forester retained by the homeowner’s association, and bi-annually thereafter. The purpose of these inspections is to identify trees that develop problems due to changing micro-site conditions and to prescribe cultural care or removal. Talbot Road Project – Preliminary Tree Protection Plan Washington Forestry Consultants, Inc. Page 8 Summary The City of Renton Municipal Code calls for 5 of the healthy, significant trees and 42.0 tree credits to be retained on the site. Based on the current site plan, 4 existing trees equaling 32.0 tree credits will be retained. One additional tree will be required to replace the 30% significant tree requirement shortfall. In addition, ten tree credits will need to be replaced. Please give us a call if you have any 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 attachments: 1: aerial photo of project area 2: site plan 3: tree list 4: individual tree rating key 5: description of tree evaluation methodology 6: glossary of terms 7: tree protection fence detail 8: assumptions and limiting conditions Talbot Road Project – Preliminary Tree Protection Plan Washington Forestry Consultants, Inc. Page 9 Attachment 1. Aerial Photo of Talbot Road Project (2019 King County) Project Area Boundary Healthy Tree Unhealthy Tree 1 2 3 4 9 10 11 12 13 14 15 16 17 18 19 20 26 25 24 23 22 21 8 7 6 5 Talbot Road Project – Preliminary Tree Protection Plan Washington Forestry Consultants, Inc. Page 10 Attachment 2. Talbot Road Project Site Plan Project Area Boundary Retained Tree Tree Protection Fence Locations 1 2 3 4 Existing house to remain Talbot Road Project – Preliminary Tree Protection Plan Washington Forestry Consultants, Inc. Page 11 Attachment 3. List of Trees on Talbot Road Project Tree # Species DBH (in.) Calculated DBH (in.) Condition Average Dripline (feet) Landmark Tree Save Based on Condition Alone? Yes or No Minimum Root Protection Zone (feet) Project Plan. Save or Remove Tree Credits Comment 1 Cypress 20 20 Good 10 Yes 10 Save 8 2 Cypress 19 19 Good 8 Yes 10 Save 8 3 Holly 17, 18 25 Good 8 X Yes 13 Save 10 4 Holly 7, 8, 10 15 Poor 8 No 8 Save 6 dying top 5 Apple 6, 8 10 Good 10 Yes 5 Remove 5 6 Apple 6 6 Good 7 Yes 3 Remove 4 7 Apple 19 19 Good 13 Yes 10 Remove 8 8 Apple 21 21 Good 15 Yes 11 Remove 8 9 Flowering Dogwood 8 8 Good 10 Yes 6 Remove 4 10 Bigleaf Maple 15 15 Very Poor 19 No 8 Remove 6 5 sprouts off old stump 11 Hawthorn 14 14 Good 12 Yes 7 Remove 6 12 Apple 10 10 Very Poor 10 No 6 Remove 5 dead top, poor tree 13 Hawthorn 14 14 Good 14 Yes 7 Remove 6 14 Cherry 5, 5 7 Good 20 Yes 4 Remove 4 15 Oregon Ash 6, 10 12 Very Poor 20 No 6 Remove 5 dead tops, mostly dead 16 Hawthorn 6 6 Good 15 Yes 6 Remove 4 17 Bigleaf Maple 22 22 Poor 20 No 11 Remove 9 topped multiple times for powerlines 18 Bigleaf Maple 18, 18 25 Poor 20 No 13 Remove 10 topped multiple times for powerlines 19 Apple 20 20 Poor 19 No 10 Remove 8 topped multiple times for powerlines 20 Cherry 6, 7 9 Poor 14 No 6 Remove 4 topped multiple times for powerlines 21 Cherry 6-12 17 Poor 18 No 9 Remove 7 4 stems, topped multiple times for powerlines 22 Oregon Ash 30 30 Poor 23 X No 15 Remove 11 topped multiple times for powerlines 23 Oregon Ash 13, 14 19 Poor 15 No 10 Remove 8 topped multiple times for powerlines 24 Cherry 14 14 Poor 18 No 7 Remove 6 topped multiple times for powerlines 25 Oregon Ash 24 24 Poor 17 X No 12 Remove 9 topped multiple times for powerlines Talbot Road Project – Preliminary Tree Protection Plan Washington Forestry Consultants, Inc. Page 12 Tree # Species DBH (in.) Calculated DBH (in.) Condition Average Dripline (feet) Landmark Tree Save Based on Condition Alone? Yes or No Minimum Root Protection Zone (feet) Project Plan. Save or Remove Tree Credits Comment 26 Oregon Ash 22 22 Poor 18 No 11 Remove 9 topped multiple times for powerlines Talbot Road Project – Preliminary Tree Protection Plan Washington Forestry Consultants, Inc. Page 13 Attachment 4. 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 RATING SYMBOL DEFINITION 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 • Major insect or disease problems • Mortality expected within the next few years Dead DEAD • Dead Talbot Road Project – Preliminary Tree Protection Plan Washington Forestry Consultants, Inc. Page 14 Cultural Care Needs: ABBRV. ACTIVITY DESCRIPTION CC Crown Cleaning Pruning of dead, dying, diseased, damaged, or defective branches over 1/2 inch in diameter –includes removal of dead tops CT Crown Thinning Pruning of branches described in crown cleaning, plus thinning of up to 20% of the live branches over ½ inch diameter. Branch should be 1/3 to ½ the diameter of the lateral branch. Thinning should be well distributed throughout crown of tree, and should release healthy, long-term branches. RC Crown Reduction Reduction of the crown of a tree by pruning to lateral branches. Generally used to remove declining branches or to lighten end weight on long branches. CR Crown Raising Pruning of lower branches to remove deadwood or to provide ground or building clearances. RMV Remove Remove tree due to decline or hazardous conditions that cannot be mitigated by pruning. RS Remove Sprouts Remove basal sprouts from stem of tree. Rep Replace Tree is small – is in decline or dead. Replace with suitable tree species. HT Hazard Tree Tree is hazardous and cannot be mitigated by pruning. Recommendation is to remove tree. None No Work No work necessary at this time. Talbot Road Project – Preliminary Tree Protection Plan Washington Forestry Consultants, Inc. Page 15 Attachment 5. Description of Tree Evaluation Methodology The evaluation of the tree condition on this site included the visual assessment of: 1. Live-crown ratio, 2. Lateral and terminal branch growth rates, 3. Presence of dieback in minor and major scaffold branches and twigs, 4. Foliage color, 5. Stem soundness and other structural defects, 6. Visual root collar examination, 7. Presence of insect or disease problems. 8. Windfirmness if tree removal will expose this tree to failure. In cases where signs of internal defect or disease were suspected, a core sample was taken to look for stain, decay, and diameter growth rates. Also, root collars were exposed to look for the presence of root disease. In all cases, the overall appearance of the tree was considered relative to its ability to add value to either an individual lot or the entire subdivision. Also, the scale of the tree and its proximity to both proposed and existing houses was considered. Lastly, the potential for incorporation into the project design is evaluated, as well as potential site plan modifications that may allow otherwise removed tree(s) to be both saved and protected in the development. Trees that are preserved in a development must be carefully selected to make sure that they 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. Trees that have developed in a forest stand are adapted to the close, dense conditions found in such stands. When surrounding trees are removed during clearing and grading, the remaining trees are exposed to extremes in wind, temperature, solar radiation, which causes sunscald, and other influences. Young, vigorous trees with well-developed crowns are best able to adapt to these changing site conditions. Talbot Road Project – Preliminary Tree Protection Plan Washington Forestry Consultants, Inc. Page 16 Attachment 6. Glossary of Forestry and Arboricultural Terminology DBH: Diameter at Breast Height (measured 4.5 ft. above the ground line on the high side of the tree). Live Crown Ratio: Ratio of live foliage on the stem of the tree. Example: A 100’ tall tree with 40 feet of live crown would have a 40% live crown ratio. Conifers with less than 30% live crown ratio are generally not considered to be long-term trees in forestry. Crown: Portion of a trees stem covered by live foliage. Crown Position: Position of the crown with respect to other trees in the stand. Dominant Crown Position: Receives light from above and from the sides. Codominant Crown Position: Receives light from above and some from the sides. Intermediate Crown Position: Receives little light from above and none from the sides. Trees tend to be slender with poor live crown ratios. Suppressed Crown Position: Receives no light from above and none from the sides. Trees tend to be slender with poor live crown ratios. Talbot Road Project – Preliminary Tree Protection Plan Washington Forestry Consultants, Inc. Page 17 Attachment 7. Tree Protection Fence Detail 6 ft. Temporary Chain Link Fence NO TRESPASSING - Protected Trees Talbot Road Project – Preliminary Tree Protection Plan Washington Forestry Consultants, Inc. Page 18 Attachment 8. 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 Forestr y 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 inspections 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.