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HomeMy WebLinkAboutFile Documents.320 N 7th St.0111-2021-BRES (15) 320 N . 7th Street Aspen , CO Tree Survey Report Prepared By: Chris Forman IBA Board Certified Master Arborist #RM-2352BM ASPEN TREE SERVICE MaY3, 2021 Est.1982 15450 HwyCarbondale CO 81623o 6 0 545 8z� (97 )9 3-30 7 RECEIVED 08/03/2021 ASPEN BUILDING DEPARTMENT PURPOSE & SUMMARY The following report pertains to 32o N.7th Street,within the city limits of Aspen, Colorado. All trees in this report are large enough to be governed by the City of Aspen Municipal Code Language. Tree species within the targeted landscaped areas consist of blue spruce (Picea pungens)and elm (Ulmus spp.). Numbers were assigned to trees in order to provide clarity to the inventory findings and can be found in the inventory table and map attached to this report. This report is designed to identify trees within the targeted landscaped area and provide individual analysis of those trees. Individual tree analysis included species type,tree diameter at breast height (DBH), overall condition, and maximum value as assigned by the City of Aspen Municipal Code. 1 tree within this inventory is in`Good'condition and 2 are in`Poor'overall condition. The trees in Poor condition should be considered for removal regardless of any future construction activities. The mitigation value of the trees assessed per City code valuation methodologies totals$32,269.39. My suggested mitigation value based upon health condition ratings totals$12,752.33. Final mitigation values are defined by the City Forester during the formal tree removal permit process, and may or may not align with the reduced mitigation values that I have assigned in this report. METHODOLOGY ASSIGNMENT Aspen Tree Service has been asked by the property owner's representative, Julia Marshall with Mt. Daly Enterprises, LLC,to inventory and assess 3 landscape trees and provide a report on their overall condition and mitigation value. The trees assessed included 2 blue spruce and 1 elm, as shown in the attached survey(Attachment A). LIMITS OF THE ASSIGNMENT This inventory assessment is based solely upon the information noted from visits to the site in April 2021. I have not performed any professional surveying, laboratory examinations, soil composition/compaction studies, or any other diagnostic techniques beyond ground level visual examination of the trees and the site. I developed general conclusions of tree health and have provided a summary based upon these observations. PURPOSE & USE OF REPORT The purpose of this report is to provide current information regarding the trees within the project scope. It is intended to be used by the property owner as an informative reference for developing a management strategy for the tree resources on the property and to inform future redevelopment planning efforts. RECEIVED 1:1 / 3/2021 ASPEN BUILDING DEPARTMENT INVENTORY Aspen Tree Service completed an inventory of targeted landscape trees on this property in April of 2021. The trees were assigned a number to correspond to the tree numbers on the tree inventory table found as Attachment B of this report. For purposes of this report, a tree stem is defined as a stem originating at the ground or attached with another stem within 4 1/2 feet from the ground. During the inventory process, each tree stem within the scope of this report was measured with a diameter tape and visually evaluated from the ground.Tree data was collected for each stem including,tree #,the Diameter at Breast Height(DBH) measured to the lower 1/2 inch at approximately 4.5 feet above ground level,tree species, and condition. Individual trees were inspected from ground level only. No advanced assessment was done in tree canopies or below existing soil levels. Condition values were assigned as a result of visual indicators such as the presence of dead limbs, signs or symptoms of disease/insects, or structural defects. Definitions of the condition scale are as follows: Excellent-A healthy,vigorous tree, reasonably free of signs and symptoms of disease, with good structure and form typical of the species. Good -Tree with slight decline in vigor, small amount of twig dieback, minor structural defects that could be corrected. Fair-Tree with moderate vigor, moderate twig and small branch dieback,thinning of crown, poor leaf color, moderate structural defects that might be mitigated by regular care. Poor-Tree in decline, epicormic growth, extensive dieback of medium to large branches, significant pathogen activity or structural defects that cannot be abated. Very Poor/Dead -Tree is in severe decline, highly hazardous or is dead. MITIGATION CALCULATION Even though the purpose of this inventory report does not include applying for a tree removal permit with the City of Aspen, a discussion regarding mitigation should be considered. We understand the purpose and objectives of the City's Tree Removal and mitigation requirements. Healthy trees are an asset to the property owner and the community. However,trees that are in poor health or structurally defected can present a safety and forest health liability for the property owner and the community. Therefore, we believe it is reasonable and appropriate to account for this liability by adjusting/devaluing the mitigation value of a specific tree based on the condition of the tree.This adjustment is made by multiplying the tree's value per the City of Aspen Municipal Code Valuation Formula by a percentage based on the tree condition.The result is an adjusted mitigation value. The following narrative details our mitigation adjustment procedure. Final tree approvals and mitigation values are ultimately made by the City Forester or his designee. Each tree stem evaluated was entered into a tree inventory worksheet noting the tree#, DBH, condition rating, comments, and the adjusted mitigation DBH. The table showing these figures can be found as Attachment B. The adjusted mitigation DBH was calculated by multiplying the actual _ RECEIVED 2gIP3/2021 ASPEN BUILDING DEPARTMENT mitigation value by the assigned mitigation percentage. The mitigation adjustment percentage ranges from o to z00%.This percentage was assigned based on the condition of the tree,forest health and the wildfire risk the tree poses to the site and area. Structurally defective trees can present a safety risk to people and/or property. Dead or declining trees pose a threat to forest health, hosting and attracting insect pests and disease becoming a point source for the spread of these pest and disease problems. Dead and declining trees can also provide a fuel source for wildfire and if they are tall, provide a mechanism for the spread of a wildfire.The following are the mitigation adjustment percentages used to quantify all of these risks.We believe this a reasonable method to maintain the City's tree removal mitigation objectives while achieving an appropriate and sustainable planting plan. Adjusted mitigation numbers can benefit the community forest by encouraging proper species, planting numbers, sizes, and spacing for site conditions, resulting in a long-term asset for everyone involved. i. i00% Mitigation—A tree scoring an Excellent or Good Condition Rating. 2. 5o%Mitigation—A tree scoring a Fair Condition Rating. 3. o%Mitigation—A dead tree or scoring a Poor or Very Poor Condition Rating. OBSERVATIONS & DISCUSSION SITE DESCRIPTION 32o N.7th Street is a residential property in the west end of Aspen, Colorado. The property has manicured landscaped areas and turfgrass on a relatively flat topography with mature spruce trees comprising most of the canopy cover on the property. The property is bordered to the south by an alley,to the west by 7th Street, and to the north and east by other residential single-family homes. TREE OBSERVATIONS Each tree was evaluated visually and entered into the attached tree inventory worksheet. This worksheet contains the tree species, condition, comments, maximum mitigation value based on the City of Aspen tree removal code language, and suggested mitigation value based upon tree condition. Deciduous trees below 6 inches in DBH and coniferous trees below 4 inches in DBH were not included in the assessment. The following information pertains to the tree observations acquired in the field during the inventory process. Tree#i is a blue spruce in overall good condition. Due to its proximity to excavation and location of the new garage to be built, it is being requested for removal. The mature spruce trees to the west of this spruce are to be protected and will remain viable canopy cover within the landscape. This tree, if permitted for removal, will likely require full mitigation per City of Aspen Municipal Code Language. RECEIVED 3 /993/2021 ASPEN BUILDING DEPARTMENT Tree #2 is an elm with a diameter of 18.5 inches in poor condition. It has a severe lean to the south over the adjacent alley. In addition to the lean,the canopy of this tree has very poor structure due to competition with surrounding trees. The property owner's representative has discussed this elm tree with the City Forester, and at that time, he advised this tree be removed due to the structural defects noted above. This tree will likely be permitted with reduced or zero mitigation. Tree#3 is another blue spruce in the southeast corner of the property. This tree has a large canker on the southwest side of the trunk with significant amounts of sap ooze visible from grade level upwards approximately 25 feet. The tree has been limbed up 25-3o feet,with very little live foliage left due to pruning and competition with surrounding trees. This tree is in overall poor health and its removal would improve the growing conditions for the adjacent trees to remain within the landscape. This tree will likely be permitted with reduced or zero mitigation. Over the past 3-5 years,there has been an increase in spruce and Douglas-fir bark beetle populations in the Roaring Fork Valley. Mature spruce trees on this property that may be subjected to construction activities within their critical root zones(an area around a tree that is 2.5 times its diameter, measured in feet) have a higher likelihood of being stressed from those construction activities. Stressed trees are more likely to be targeted by bark beetles. The mitigation value for all the trees assessed in this report totals$32,269.39, per the City of Aspen's tree valuation equation. The suggested mitigation value for the trees after applying the condition ratings that I've assigned totals$12,752.33. Final mitigation values and approval for tree removals are determined by the City Forester as part of the formal tree removal permit process. RECEIVED V3493/2021 ASPEN BUILDING DEPARTMENT PHOTOS •% ,y' �i... •'•1 •- - '? •'� /' ♦ `�?{ II 4 pttsv.,, • (,• `( 1' ,./ ti ,'•��' {'may• - •ry �( �,1 .{, ,. ,I J •9• - .. ,{, •><• ''lam , •I r. `1 •Or i 41 la ,_. ,,, ...,: Photo i. Tree#i in Good condition located in footprint of new garage. 51 /9 3/2021 ASPEN BUILDING DEPARTMENT ',I �� / Si t: ,Sill t'•r ': ,i_=ter e 1 I ji ri l N `t"4j�y l., T ` • . *.," - • I-g Z,r,l `\ `"l, 5; ; t ' ' • .y. t1r. ',J.' 1 t t` l _ jI .. .-4.- ,,,, , -----, .= '' k ems" s, a� � S��h,r \L Photos 2&3. Elm \ `, with severe lean and '� - ; T • tE. nr poor canopy - 'v"f ! , �? ', �` f>. structure. - 1 l 1 Y� i V h `)4410. Y ' •^1! ter. , �•_/ RECEWED M3h93/2021 ASPEN BUILDING DEPARTMENT • l ` :.{it t �` ' ram•,.;) r am'„• A,.. 4 Si IP. OCS. 4 --_,L, , ,,,,,,,„, 4. . s ..„,....4 ,i. 3.,,,..,.x .,, ..„,,,,,,..„ . , ., . .,.„ 4,, , . .., m:. , , : , ,,,,,, sl f r • V. ` 'J`l3 77 A1 3 ] �,�}' ' 71 �itt4 c Vrit r 'r' e r } w '`' ; i Photos 4&5. Spruce r '� I � !� i tii, #3 with canker in V,'�s-, j w 4, `' ` ; ` ;.. trunk, limbed up,and ,R' r �,. • 4,.+ �' very little live foliage left within tree crown. 0 �Y.b`' cf.. it +' ` m ti4- ,' t, ,,, , - -,, r. . . - - -, .....ile. .. ..,";,...ot. Cjy��..,4. t , r `_ P�.t�( , i . .1::.,..-- k.';.?'1'414,*.' '• 0 3t,'�` C.41k"..' ' .'/ii ) f; $, ``. ` Olt.zit 0 � „I ,w ' a ''� Ali• Rr , , p /gO3/2021 ASPEN BUILDING DEPARTMENT CONCLUSIONS Based upon my assessment,trees#2 and 3 are in Poor condition and should be considered for removal regardless of future construction planning. Tree #i is in Good condition and will likely require full mitigation if the City Forester permits its removal. Spruce trees that are larger than 14 inches in diameter may be targeted by bark beetles if construction activities are to occur within their critical root zones. Specific protection measures for these trees should be considered. All tree removals require a permit from the City of Aspen and final mitigation requirements are determined by the City Forester or his designee. RECEIVED M /g93/2021 ASPEN BUILDING DEPARTMENT Attachment A 32o N. 7th St Trees \- •40P ,,,,_ C Pitkin Maps&More .. air El Map Created on 2:21 PM 05/03/21 at http://www.pitkinmapsandmore.com ..., + i ------ Mil, rt_F- . I � 3t . -ft- 1 lir* i, ZY.rCQ?�� �0 W Legend Cr•, 1 j �� 1' ! State Highway �`_ it Road Centerline 4K ���_ I =, Primary Road r. -----J - • Secondary Road f ,- W f NC Service Road 11 h �i _ i' _ T Full Address i , '•7;33. -fig it---�_ Parcel Boundary II , '.-_ • J 2 � 'L�'.c1-i/ - _- --__ Rivers and Creeks j �`_— ---_ i I ---- II _ I� I �,� + Continuous E• '�L�'17 4.t;fr,•61Vall ' i' Intermittent . Qt lAlfU. _ i' _ t. 1i •`--- ' '• I L — I i�• River,Lake or Pond 11 �.i I 'i 2 -- J'i r V/i, (+ Town Boundary 3 J(fJ ,� • Federal Land Boundary i-H- -IL r(8�sw na. ---I: C BLM j---- HALLAM ST l .4,i 0 State of Colorado --'1��•:i El USFS i / o •-•11111fir.:44' 1. . • • -,' / )11---------E-- ____r , (0 lot L'..__790W iv• . i -.. . _ LEA M' _,L_/r '1l r au, � L r 1 � Notes I --_____ __, / _ r 1 • • AC 188.1 0 94.04 188.1 Feet THIS MAP IS FOR INFORMATIONAL PURPOSES. x Pitkin County GIS makes no warranty or guarantee �E •,�/EIV' .a 'D- 1:1,128 concerning the completeness,accuracy,or reliability WGS_1984_Web_Mercator_Auxiliary_Sphere Q of the content represented. 0 8/0 3/2 0 21 ASPEN BUILDING DEPARTMENT Attachment B 320 N. 7th Street Tree Inventory Aspen Tree Service May, 2021 Suggested Tree #of Mitigation Species DBH Mitigation Condition Comments ID# Stems Value Value 1 Blue spruce 1 19 $ 12,752.33 $ 12,752.33 Good Tree in overall good health; removal for construction efforts 2 Elm 1 18.5 $ 12,089.98 $ - Poor Severe lean over alley; poor canopy structure 3 Blue spruce 1 14.5 $ 7,427.08 $ - Poor Canker on southwest side of tree; limbed up; decline in overall health Totals 52 $ 32,269.39 $ 12,752.33 RECEIVED 08/03/2021 Page lof 1 ASPEN BUILDING DEPARTMENT