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HomeMy WebLinkAbout2024-10-08-TREE-min-attach Lexington Tree Management Manual APPENDIX XIV LEXINGTON TREE BYLAW RULES AND REGULATIONS When does the Tree Bylaw apply? Lexington's Tree Bylaw (http://ecode360.com/10535335) applies to trees 6" DBH or greater (or multiple trunk tree totaling 15" or greater) in the setbacks ("protected trees") of properties undergoing demolition or major construction, i.e., new construction or the increase of a building's footprint by 50% or more. An example of the setback is shown below. The Tree Bylaw setback may be different than the property's zoning setback. rear of property) 15 feet UNRESTRICTED AREA See definition of setback in Appendix 1,§120-3. o 15 feet 15 feet 30 feet Front of property:Town right-of-way 1. Tree Protection Plan In accordance with sections § 120-8B(2) and § 120-8D, when major construction or demolition is planned, the owner of the property shall submit to the Town a tree protection plan prepared by a Certified Arborist for any Protected Trees that are to be retained on the site and for any trees in the Town right of way. The Tree Warden must approve any actions that will affect public shade trees. All tree protection measures including installation of Tree Save Area fencing and root pruning to reduce the Tree Save Area on trees whose critical root zones will be encroached upon by construction activities must be completed, documented and submitted to the Town by a certified arborist before any ground disturbing activities, including demolition or tree removal, begins. 100 Lexington Tree Management Manual a) The fenced Tree Save Area is defined as the area within the drip line of a tree, or a circle with a radius from the tree trunk of one (1) foot for every inch of DBH, whichever is greater, unless the Tree Save Area will be reduced by root pruning. If the certified arborist determines the protective fencing cannot be installed at the drip line, then proper root pruning and trunk protection should be carried out. Ideally the minimum distance from the trunk to the fencing will be six (6) feet. See Figure 13 and sections d), f) and g) below. b) Fencing must be 5' or higher high chain link or welded wire attached to stable metal posts or stakes set securely in the ground, spaced a maximum of eight (8) feet apart. c) Each fenced Tree Save Area shall include signs reading, "TREE SAVE AREA— PLEASE KEEP OUT'7 "AREA DE AHORRO DE ARBOLES — ENTRADA PROHIBIDA POR FAVOR", in both English and Spanish d) Tunneling is preferred to root pruning, where possible. See Figure 14. e) Root pruning should be performed prior to any excavation or demolition and only by or under the supervision of a certified arborist. See Figure 14. i) Excavate using an air spade, hydro excavation or hand tools to expose roots. ii) Cut roots cleanly, removing no more than 40% of roots. iii) Backfill and water immediately. iv) If the hole must be left open past the end of day, cover roots with wet burlap. v) Monitor tree health and supply adequate water and mulch. f) If a grade change is needed within the critical root zone, root pruning is required before that grade change is made. Create terraces with retaining walls to maintain the original grade around the retained critical root zone. See Figure 15e g) Trunk Protection: If a certified arborist determines that protective fencing cannot be installed to protect the tree trunk then trunk protection should be installed. Loosely tie protective 2x4 lumber around the tree trunk with rope, do not use wire. Attach the rope to the 2x4's using staples. Do not drive fasteners into the tree. Height of the lumber shall be from the tree base including root flare to the bottom of the first branch, typically 6-8'. The 2x4 lumber should be angled so the trunk flare and buttress roots are also protected. Closed cell foam padding, one-quarter ('/4) inch thick minimum, can be placed between the trunk and the lumber for added protection. h) Soil Protection: Avoid compaction of the soil by keeping foot and vehicle traffic and storing of materials away from the root zone and outside the Tree Save Area. In cases where allowing access through the tree save area is unavoidable as determined by the certified arborist, either a minimum one-half('/2) inch steel plate placed on top of a two (2) inch minimum bed of mulch (e.g. wood chips) or a minimum of three-quarter (%) inch plywood over a four (4) inch bed of mulch may be used to bridge over the protected root zone in the tree protection area. i) Any changes during the course of construction that will impact an existing Tree Save Area requires that an updated Tree Protection Plan by a certified arborist be installed, documented and submitted to the Town before that work may commence. j) All tree protection fencing will remain in place until landscaping begins. 101 Lexington Tree Management Manual 2. Removal of a Protected Tree In accordance with section § 120-8, in order to remove a Protected Tree, the following will be required: a) A completed and signed Tree Removal and Mitigation Permit ication b) A signed Tree Removal and Mitigation Permit issued by the Tree Warden via the Town's ViewPoint Cloud online permitting portal. c) Mitigation of the removed protected tree(s) as described in sections 5 through 7 below. 3. Removal of a Hazardous and/or Dead Protected Tree In accordance with section § 120-9, in order to remove a Protected Tree that is hazardous or dead and avoid mitigation the following will be required: a) A completed and signed Tree Removal and Mitigation Permit application b) A completed and signed International Society of Arboriculture ("ISA") basic Tree Risk Assessment Form related to the Tree provided by a Certified Arborist, submitted with the permit application. c) A signed Attestation from a Certified Arborist using the attached form, submitted with the permit application. d) Photographs of the Protected Tree, including full tree view and the area of the hazardous tree where the dead or hazardous area(s) can be observed, submitted with the permit application. e) A signed Tree Removal and Mitigation Permit issued by the Tree Warden via the Town's ViewPoint Cloud online permitting portal. 4. Removal of an Invasive Protected Tree In accordance with section § 120-9, in order to remove a Protected Tree that is an invasive species and avoid mitigation the following will be required: a) A completed and signed Tree Removal and Mitigation Permit application b) Identification of the Protected Tree by a certified arborist as a species on the attached List of Exem t Trees. c) Photographs of the Protected Tree, including a full tree view and the area of the invasive tree where its species can be observed, submitted with the permit application. d) A signed Tree Removal and Mitigation Permit issued by the Tree Warden via the Town's ViewPoint Cloud online permitting portal. 102 Lexington Tree Management Manual 5. Calculation of Replacement Inches for Mitigation In accordance with section § 120-16, mitigation will be calculated in terms of"replacement inches" according to this table: Replacement Inch Calculation Table Level Removed Tree Replacement Inches Level Less than 24" DBH; or a tree of any size Same as inches 1: to be removed in order to comply with a removed condition, restriction or requirement of a local, state, or federal permit Level 24" DBH and larger 4 times inches 2: removed 6. Mitigation of Removed Protected Trees In accordance with section § 120-8C, when a protected tree is removed at least one of the following is required: a) Replanting one (1) inch caliper of new tree(s) for each replacement inch of trees removed. New trees must be 3" caliper or larger. Evergreens must be a minimum of 6' in height. The only arborvitae that will be accepted for mitigation planting is Thuja plicata x Standishii, Green Giant Arborvitae. b) Replanting one-quarter ('/4) inch of new tree(s) from the Large Shade Tree List (Section V.13.5 of the Lexington Tree Management Manual and attached) for each replacement inch of tree(s) removed. For example, a three (3) inch caliper tree from this list will be credited with twelve (12) inches of mitigation planting. Columnar or dwarf cultivars that are not at least forty (40) feet high x thirty (30) wide at maturity do not qualify as large shade trees. c) Payment to the Lexington Tree Fund of two hundred (200) dollars per replacement inch not already mitigated by replanting. This provision is not allowed until the requirements of section 7 below are satisfied. d) Minimum street frontage planting as described in section 7 below must be completed before mitigation planting elsewhere on the property is credited or payment to the Tree Fund in lieu of replanting is allowed. 103 Lexington Tree Management Manual 7. Minimum Street Frontage Mitigation Planting In accordance with section § 120-8C5, when mitigation for the removal of protected tree is owed, the following will be required: a) Replanting is required only until the mitigation owed is accomplished or the desired minimum street-frontage spacing is achieved, whichever occurs first. b) Minimum street frontage planting must be completed before mitigation planting elsewhere on the property is credited. c) Trees will be planted in the front setback or the town right-of-way to achieve no greater than a 35' gap in between trees located in the combined area of the Town right of way and the front setback of a property, and no greater than a 35' gap from a tree to the property line, as measured along the street frontage. d) Planting in the front setback is preferred. Planting may occur in the Town right-of- way with permission of the Tree Warden. e) Replanted trees shall be selected from the Large Shade Tree List, unless there are mitigating circumstances as delineated in the Tree Planting Guidelines. f) From the standpoint of creating public shade, a small tree under wires will be considered equally as good as a large tree farther back on the lot. Small trees planted near streets and sidewalks should have upright or vase shapes when mature so as to not impede vehicular, bicycle or pedestrian traffic. Recommendations may be found in the list of Best Small Street Trees Under Wires. g) Consider medium-sized trees (-40' mature height) when a larger tree would shade solar panels on the front of the house. h) These requirements are subject to availability of suitable planting sites, as delineated in the Tree Planting Guidelines. 8. Survival of Retained Protected Trees and Mitigation Plantings In accordance with sections § 120-8C(6) and § 120-8D(1), retained protected trees and new trees planted for mitigation credit must be maintained in good health for 1 year from the date the Certificate of Occupancy is issued. If a retained protected tree dies or is removed in this time period, the owner of the property will provide mitigation for the dead or removed tree. If a tree planted as mitigation dies within 1 year, the owner of the property will replace the tree within 9 months. 104 Lexington Tree Management Manual FIGURE 13 PROTECTING TREES DURING CONSTRUCTION dripline dripline 6' min Tree Save Area acritical foot Zoite---- i • Install a protective fence to create a Tree Save Area. The Tree Save Area is defined as the area within the drip line of a tree, or the area within a radius around the tree trunk of 1 foot for every inch of DBH, whichever is greater. • Use 5' high or higher chain link or welded wire with stable metal stakes or posts inserted in the ground and spaced a maximum of eight (8) feet apart. • If protective fencing cannot be installed at the dripline of a tree, then it should be installed as far away from the tree trunk as possible, ideally a minimum of six (6) feet. • Each fenced Tree Save Area shall include signs reading, "TREE SAVE AREA— PLEASE KEEP OUT'7 "AREA DE MORRO DE ARBOLES — ENTRADA PROHIBIDA POR FAVOR", in both English and Spanish and should be placed in a highly visible location. • Tree protection shall be placed before ground disturbing activities, including tree removal and demolition, start and shall remain in place until all construction has been completed. • Trunk Protection: If the protective fencing cannot be installed to protect the tree trunk, then trunk protection should be installed. Loosely tie protective 2x4 lumber around the tree trunk Lexington Tree Management Manual with rope, do not use wire. Attach the rope to the 2x4's using staples. Do not drive fasteners into the tree. Height of the lumber shall be from the tree base including root flare at the bottom of the first branch, typically six to eight (6-8) feet. The 2x4 lumber should be angled so the trunk flare and buttress roots are also protected. Closed cell foam padding, one-quarter ('/4) inch thick minimum, can be placed between the trunk and the lumber for added protection. • Soil Protection: Avoid compaction of the soil by keeping foot and vehicle traffic and storing of materials away from the root zone and outside the Tree Save Area. In cases where allowing access through the tree save area is unavoidable either a minimum one-half ('/2) inch steel plate placed on top of a two (2) inch minimum bed of mulch (e.g. wood chips) or a minimum of three-quarter (%) inch plywood over a four (4) inch bed of mulch may be used to bridge over the protected root zone in the tree protection area. • Take special care with backhoes and other machinery to minimize damage to roots, trunk, limbs and overhead branches. The best time to plant a tree is twenty years ago. The next best time is now. Chinese Proverb 105 Lexington Tree Management Manual Figure 14 EXCAVATION and TUNNELING WITHIN DRIIPLINE dripV= 0'm ill rlrmtwluumu f4o"' saves roots 711 10"YA, "I'tAN" L I N 6 PiMNING • Excavate around brae roots or tunnel under the root zone. TrencNnq without proper root pruning can severely damage roots. • Tunneling is preferred to root pruning, where possible. • Root pruning by or under the supervision of a cartified arborist must be done prior to e,xcavation or grade change any time work encroaches on the critical root zone, * Excavate using an air spade, hydro excavation or hentools to expose roots, * Cut roots deartly, rernoving no more than forty (40) percent of roots c) Backfill and water irnmedWely If the hole must be left open past the end of day,, cover rots with wet burtap 106 Lexington Tree Management Manual Figure 15 GRADE CHANGE GUIDELINES new bade A5 r 4 ry '*A �Y'k�5P6CbC1.w,�tl'�4L��„ r MAINTAIN EXISTING GRADE AROUND TREE E Protect to t trees by creatingterraces with r,etaining walls to maintain the rarm drm l grade around the root zone. Cutting u r shavw ng routs or pifing soil on top of roots to create rwtlruw ous,new grave wbwtldl slowly lwtrd the tree, Avoid drainage changes that cDuld rruearu a tree gets too much water or not enough, If a grade change is needed within the critical root zone,, rot pruning ls requirerd before that grade change is made. See Figure 114,. 107 Lexin ton Tree Mana ement Manual 'Tarw Assmment ke Fattofs and tes Profile Factors Ttee befects And Conditions Afteft Ohme Ukeffiaadl of faller 108 Lexin ton Tree Management Manual ................................................................................................................................................................ PAsk CstegwUsftni ---- ---- ---- ---- ------------- --- -------- ------- - ------- Uktll%oW of Impatt of FIABrous I Low Mwim 8 HA Pmbabbe UvAhri Vftfilk LAM .............. what Hka,11L m rabobta OWiefy k"Wy LWAkoly UnUkAy Lk*Nhoadof con""OK"of Faft" www ww � ww >B ca Nnor S*"Ificalit Saw&* .......... ......................... ............... ............... II Modmate Bea Extreme Like Moderate M &,a sof"dwhat B p waaa Lew Mave ideriste Nitaderatr UwkjA*Ov Low LOW 'UYW WN 109 Lexington Tree Management Manual bus MOR�� O� 1775 tic Town of Lexington D r - Department of Public Works 3 an APRIL 19' �FXI NGS�� Attestation of Certified Arborist Date I certify that: 1. It is my professional opinion that the tree (the "Tree") identified in the accompanying permit application and ISA Basic Tree Risk Assessment form (the "Assessment Form"), in accordance with a Level 2 ISA, BMP Tree Risk Assessment, is dead or at high or extreme overall risk and that no alternative reasonable mitigation of the risk exists other than by the removal of the Tree; 2. I have personally overseen the inspection of the Tree and the property on which it is located (the "Property") that is referred to in the attached Assessment Form and this Certification and have stated my findings accurately. The extent of my assessment of the Tree is stated in the attached Assessment Form; 3. I have no current or prospective ownership interest in the Property associated with the Tree that is the subject of this Assessment Form and Certification, and I have no personal interest or bias with respect to the parties involved; 4. The analysis, opinions and conclusions stated herein are my own; 5. My compensation associated with this ISA Basic Tree Risk Assessment and this certification is not contingent upon the reporting of a predetermined conclusion that favors the cause of the owner of the Property or any other party; and 6. All of the above statements are made in my professional judgment in accordance with standards of conduct required for certified arborists. Signature ISA Number MCA Number 110 Lexington Tree Management Manual LEXINGTON INVASIVE TREE LIST FOR TREE BYLAW EXEMPTION Common Name Scientific Name sycamore maple Acer pseudoplatanus tree-of-heaven Ailanthus altissima autumn olive Elaeagnus umbellate European buckthorn; glossy buckthorn Frangula alnus; Rhamnus frangula melaleuca Melaleuca quinquenervia catclaw mimosa Mimosa pigra Amur cork-tree Phellodendron amurense Japanese black pine* Pinus thunbergii* Callery (Bradford) pear** Pyrus Calleryana** large gray willow Salix atrocinerea; Salix cinerea ssp. oleifolia gray willow; rusty willow Salix cinerea *Listed in 2017. As of 12/31/2022, nursery agents/growers may no longer receive or begin propagation. Existing stock received or propagated before this date may be sold until 12/31/2025. This tree will not be accepted as mitigation planting. ** Listing on the MA Prohibited Plants List expected by the end of June 2024, after a 2022 recommendation by Mass. Invasive Plants Advisory Group. Even if commercially available after this date, this tree will not be accepted as mitigation planting. Why we have excluded from exemption two trees that are on the MA Prohibited Plant List. Acer platanoides (Norway maple) Widely planted as a replacement for American Elm in the early 20th century, Norway maple represents such a large percentage of Lexington's tree canopy that we cannot encourage its wide-scale removal at this time. Exemption from the mitigation requirement of the bylaw does not accurately reflect the value of mature Norway maples. Many municipalities advise that small specimens be removed, and mature ones allowed to live until they decline, at which point they should be replaced with native canopy species. Robina pseudoacacia (Black locust) While the species is native to central portions of Eastern North America, it is not indigenous to Massachusetts. It has been planted throughout the state since the 1700's and is now widely naturalized. It behaves as an invasive species in areas with sandy soils. Black locust seeds do not disperse as widely as do Norway maples, and the trees support many forms of wildlife. The tree's presence in pockets in Lexington provides much-needed 111 Lexington Tree Management Manual shade. As with Norway maples, removal of seedlings and gradual replacement of declining mature trees is a practical approach that retains tree canopy. LARGE SHADE TREE LIST Large shade trees for 4x mitigation credit have a mature height of at least 40' and spread of at least 30'. No columnar cultivars qualify unless they meet those criteria. Trees not native to New England were included only if they offered characteristics that may be hard to find in native trees available in 3" caliper size. No western trees are included. Common Name Scientific Name Acceptable Attributes cultivars Bald Cypress Taxodium distichum (native to `Monarch of Illinois' Pyramidal deciduous conifer southeast/mid-Atlantic) 50-70'h x 20-30'w, suitable street tree Basswood Tilia americana (NE native) 60-80'h x 30-55'w, salt-sensitive Birch, River Betula nigra (NE native) 40-70'h x 40-60'w, exfoliating bark, suitable street tree Birch, Black or Betula lenta (NE native) 40-55'h x 30-45'w, fall color Sweet Black Walnut Juglans nigra (NE native) 50-75'h x 50-75'w, oval to rounded crown on tall trunk at maturity Butternut Juglans cinnera (NE native) 40-60'h x 30-50'w Catalpa, Northern Catalpa speciosa (NE native) 40-60'h x 20-40'w, pannicles of bell-shaped flowers Cherry, Black Prunus serotina (NE native) 60-90'h x 35-50'w, small white flowers and black fruits Elm, American Ulmus americana (NE native) DED-resistant: 60-80'h x 50-70'w, vase shape, `Princeton' suitable street tree. U structure `Jefferson' branching (Jefferson) preferable to `New Harmony' V structure (Princeton), `Valley Forge' Hackberry Celtis occidentalis (southern 40-60'h x 40-60'w, cylindrical at NE native) maturity, suitable street tree tolerates urban environments Hemlock, Tsuga canadensis (NE native Not used as hedge 60-80'h x 25-40'w, fine-textured Canadian or needled evergreen. Placement on Eastern cool, damp N slope critical for tree's health and survival. May require treatment for wooly adelgid. Hickory, Carya ovata (NE native) 50-100'h x 20-40'w, few pests or shagbark diseases, fruit can be litter problem Honeylocust Gleditsia triacanthos inermis Shademaster, 50-60'h x 25-35'w, casts open light (midwest native) Skyline, Halka shade, suitable street tree Kentucky Gymnocladus dioicus (Midwest Male cultivars only 60-75'h x 30-50'w, tolerant of tough Coffeetree native) conditions and unattractive for much of year, best used as street tree, not specimen tree Magnolia, Magnolia acuminata (NE 50-80'h x 50-80'w, flowering Cucumber native) Maple, Red Acer rubrum (NE native) 40-70'h x 20-40'w, fall color, suitable street tree Lexington Tree Management Manual Maple, Sugar Acer saccharum (NE native) `Fall Fiesta' 75'h x 30-50'w, needs lots of `Commemoration' ground space and water for health `Flash Fire' and survival, not suitable as street `Green Mountain' tree Oak, Black Quercus velutina (NE native) 50-60'h x 50-60'w, not suitable as street tree Oak, Bur Quercus macrocarpa (native to 70-80'h x 70-80'w, excellent park central plains) and large area specimen tree, suitable street tree Oak, Chestnut Quercus montana (NE native) 60-70'h x 60-70'w Oak, Pin Quercus palustris (NE native) 75'h x 40'w, downward branching makes unsuitable next to street, good as setback tree Oak, Red Quercus rubra (NE native) 75'h x 30-45'w, suitable street tree Oak, Scarlet Quercus coccinia (NE native) 75'h x 40-50'w, late scarlet or russet fall color, not suitable street tree Oak, Swamp Quercus bicolor(NE native) 50-60'h x 50-60'w, drought White resistant, easier to transplant than white oak, yellow fall color Oak, White Quercus alba (NE native) 50-80'h x 50-80'w, good park/meadow tree, slow growing, not suitable street tree Pine, Eastern Pinus strobus (NE native) Many 50-80'h x 20-40'w, needs sun, easy White to transplant, branches break in high wind, not suitable street tree Sassafrass Sassafras albidum (NE native) 30-60'h x 25-40'w, 3 forms of leaves, hard to transplant, forms colonies, not suitable street tree Sweetgum Liquidambar styraciflua (native 60-75'h x 40-50'w, beautiful to southern NE) variable fall color, messy fruit, suitable street tree if roots have enough room Sycamore, Platanus occidentalis (NE 75-100'h x 75-100'w, massive trunk American native) with flaking bark, open crown, good street tree Tuliptree Liriodendron tulipifera (NE 70-90'h x 35-50'w, fast-growing tall native) tree with tulip-shaped leaves and greenish-yellow flowers, some cultivars suitable as street trees Tupelo Nyssa sylvatica (NE native) `Wildfire' Glossy green leaves with bright fall `Green Gable' color, bluish black fruit, suitable street tree Yellowwood Cladrastis kentukea (native to 30-50'h x 40-55'w Broad, rounded southeast) crown with panicles of white, fragrant flowers, not suitable as street tree due to low branching; good setback tree Lexington Tree Management Manual 113 ACCEPTABLE TREE PLANTING SITE GUIDELINES Unless otherwise specified, numbers given are minimum distances from tree center: at least 3' x 6' or 16 square feet with minimum Tree pit size width of 3' (Low oxygen trees preferred for small spaces) Distance from curb edge, where street has curb 30" Distance from adjacent trees 15'-40', varies with species Distance from street intersections 20' Distance from driveways 5' Distance from fire hydrants 10' Distance from underground utility lines 10' Distance from gas or water valve 10' Height of trees under utility lines 30' maximum at maturity Distance from street lights 10', varies with species Distance from utility poles 15' Distance from stop sign 20' Distance from traffic signs Depends on sightline requirements Distance to opposite obstructions 5' Suggested distance from parking meters 5' Passage for ADA considerations 3' wide sidewalk Passage for sidewalk plows 5' wide sidewalk Distance from house 20' Distance behind overhead wire for large tree 10' Mitigating circumstances would shade solar installation within 10 years. Less than ideal conditions will be evaluated on a site-by- site basis. Lexington Tree Management Manual 114 BEST SMALL STREET TREES UNDER Wimco Less than 30'h, upright or vase shaped at maturity, salt and drought tolerant. Common Scientific Name Acceptable Attributes Suitable for Name cultivars curb strip planting Alleghany Amelanchier laevis 15-30'h x 8-18'w, early Only single Serviceberry (NE native) showy white flowers, fall stem color Amur Maackia 20-30'h x 20-35'w, fragrant No Maackia amurensis (non- white midsummer flowers native Canada Red Prunus virginiana Canada Red', 20-25'h x 15-20'w, green Only single Chokecherry 'Canada Red'(NE 'Shubert' spring leaves turn purple in stem native) summer, white flowers and small redish- ur le fruits Crabapple Malus spp. Columnar Showy flowers, fruit No types such as `Adirondack' `Sentinel' `Strawberry Parfait' European Sorbus aucupani 25-30'h x 15-25'w, showy Only single Mountain (non-native) flowers and fruit, EAB stem Ash resistant Flowering Prunus sargentii `Accolade' 15-25'h x 15-25'w, showy No Cherry (non-native) 'Amanagawa' flowers, fruit, short-lived or Prunus `Royal serrulata (non- Burgundy' native) and others Hawthorn Crataegus viddis or 'Winter King', 25'h x 25'w, mainly thornless, No phaenopyrum 'Princeton red fruit persist in winter (native to Sentry', southeast) 'Fastigiata' or other upright thornless varieties Japanese Styrax japonicus 20-30'h x 15-25'w, showy No Snowbell non-native bloom Sweetbay Magnolia virginiana 10-20'h x 8-15'w, fragrant No Magnolia (NE native) white late spring flowers and small red summer fruit Lexington Tree Management Manual 115 115