March 3, To: Andrew Cohen-Cutler, Associate Planner. City of Calabasas. From: James Dean, A.S.L.A., I.S.A. City Arborist

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1 March 3, 2009 To: Andrew Cohen-Cutler, Associate Planner City of Calabasas From: James Dean, A.S.L.A., I.S.A. City Arborist Applicant: Ken, LLC, Kavoos Ahankoob, File No Re: Recommended conditions for the care, maintenance and monitoring of oak trees located at 5349 Las Virgenes Road, APNs: , and SECTION 1: Introduction The Oak Trees located on the above mentioned APNs have been seriously affected as a result of encroachment into the Protected Zones [as defined in the Calabasas Oak tree Preservation and Protection Guidelines (revised April 29, 1993) (Guidelines) by mechanical equipment during Geotechnical exploration and yearly weed abatement. I personally observed the damage on December 17, There were no oak tree permits applications reviewed by this office prior to this encroachment as required by the Calabasas Municipal Code, Section (D) (3). As I am the City Arborist for Calabasas I am required to review all applications for oak tree permits. In this case, the applicant, Ken, LLC, Kavoos Ahankoob (Applicant), applied for a Retroactive Oak Tree Permit in partial compliance with the conditions of a Notice of Violation/Director s Stop Work Order dated December 13, The Applicant applied for the required permit on April 30, As part of that application, the Applicant provided an Oak Tree Report, prepared in accordance with the Guidelines, by McKinley and Associates. Based on the McKinley Report and my personal observations at the above mentioned site, there are 36 oak trees located within the area of unpermitted grading. These Protected Zones of these 36 oaks have been encroached upon in varying degrees ranging from minor encroachment (more than 10% but less than 15%), to moderate encroachment (`16% to 25%) and finally severe encroachment (26% to 100%). The 26% to 100% range is large because the grading that has impacted these percentages of the root zones will most likely cause a disruption of the normal growth and vigor of the tree. Any disruption of 26% or more of the root system will disrupt root growth and cause growth pattern changes, by the tree, to compensate for the disruption to the root system continuity. These changes place the tree in jeopardy and threaten the impacted tree s long term viability. Site inspection confirms that the level of damage varies from tree to tree. There are several cases where the soil located within the Protected Zone of individual trees has been excavated to shallow depths and/or scarified. There is also evidence of soil surface compaction within the Protected Zones of many of the encroached upon trees. 1

2 The effect of the non permitted encroachment caused by the non permitted grading will be the short and long term weakening of the individual trees in the work area. Evidence of a weakened tree is manifest visually by the presence of main-stem dieback at individual trees. The result of this weakening will add to the level of stress upon the individually affected trees which in turn will favor the advancement of any disease present and/or hasten the demise of individual specimens through the reduction of nutrient transport through the newly disrupted root system. Clearly, disease has been present in some of the trees for an indeterminate time prior to the non permitted encroachments; however, the long term adverse or even fatal effect as a result of the non permitted encroachments will likely not become visible until sometime in the future. Of the thirty-six (36) oak trees where the illegal and non permitted encroachment into the Protected Zones occurred, thirty (30) trees suffered reportable damage. In light of the damage inflicted by the non permitted grading and the resultant non permitted encroachment into the Protected Zones of the 36 oak trees located in the work zone, I have prepared a plan that details the remediation, weed control and monitoring program as proscribed by the Calabasas Municipal Code, Section and The Oak Tree preservation And Protection Guidelines (Guidelines). [Section 2] Based on my experience and expertise in this area, it is my professional opinion that one (1) of the thirty (30) damaged and trees might die as a result of the unpermitted encroachment. I have selected a tree where the Protected Zone has been impacted 100% and prepared a replacement cost analysis as proscribed by the Calabasas Municipal Code, Section and the Guidelines. [Section 3] I have prepared an estimate of costs associated with all remedial oak tree work. The analysis includes the cost estimates for restoring the Protected Zones to their original conditions, installation of protective fencing and other remedial work as proscribed by the Guidelines, (Sections VII, IX, X, Appendix E), and Section of the Calabasas Municipal Code. [Section 4] The following plans are stipulated by the Guidelines and Section for the purpose of restoring the 36 encroached upon Protected Zones surrounding the trees located within the area of non permitted grading. The requirements are based on actions proscribed by the Guidelines and Section (E) (3) which states that the Condition or location of the oak tree or scrub oak habitat requires altering to maintain or aid its health balance or structure, and Section (G) (6). These two sections are pertinent because the non permitted grading has caused deleterious condition to occur at the oak trees where grading encroached upon the Protected Zones and all of the actions outlined below will serve to help in rectifying the damage and improving the health of the existing oak trees. Section 2: Remediation Plan: 2

3 The Owner shall submit a written Work Procedures Plan (hereafter the Plan ), prepared by a California licensed Landscape Architect or Certified Arborist, to the Planning & Environmental Programs Division (hereafter the Division ) listing the 36 encroached upon oak trees for review and approval by the Planning Commission. As stipulated in the Guidelines, I have reviewed the application submitted by Ken, LLC, Kavoos Ahankoob, for a retroactive oak tree permit. Accordingly as part of this review, it is my recommendation that, as part of the overall restoration plan for the 36 encroached upon Protected Zones, that a Weed Abatement Plan be implemented immediately, and continued for a period of five (5) years. The implementation of the following program will serve to help in rectifying the damage and improving the health of the existing oak trees as stipulated by the Calabasas Municipal Code, Sections (E) (3) and (G) (6). In addition, the Owner shall establish a five (5) year monitoring program as outlined in Section (G) (7). All monitoring shall be in accordance with the procedures adopted in the Guidelines. 2.1 The proposed Work Procedures Plan shall concern protective fencing and sign installation for the thirty-six (36) encroached upon oak trees and their Protected Zones [as defined in the Calabasas Oak Tree Preservation and Protection Guidelines (revised April 29, 1993)] - hereafter the Guidelines that pertain to care and protection of oak trees as stated in: Section VIII [Standards for Performance ] Section IX [Tree Maintenance], Section X [Phases of Construction], and Appendix E [Standard Designs For Encroachments Within The Protected Zone] shall be incorporated into this part of the Plan. The protective fencing shall be a minimum 5 foot high chain link fence with posts installed every 8 feet and embedded 1.5 feet deep into the natural grade at the outermost edge of the protected zone of each oak tree. Exceptions to the above mentioned fencing requirement may occur in cases where oak trees are located on slopes that will not be grubbed or graded, or are located in areas where there is no activity is planned or no currently approved grading plan. The fences must be installed in accordance with the approved fencing plan and approved by City inspection prior to the commencement of any restoration grading operations. The applicant s job supervisor will be responsible for providing 48 hours advance notice to arrange for the inspection. 3

4 Signs must be installed on the fence on the cardinal points (north, south, east, and west) around each tree. For groups of trees, signs will be placed at approximately 50 foot intervals around the grove. The signs must be a minimum of 2 feet square and must contain the following statement: 4 WARNING THIS FENCE IS FOR THE PROTECTION OF THIS TREE AND SHALL NOT BE REMOVED WITHOUT WRITTEN AUTHORIZATION OF THE CITY OF CALABASAS. 2.2 Section 2 of the Plan shall concern actions to be undertaken on the thirty-six (36) injured or encroached upon trees and/or their root systems. These shall include, without limitation, the following activities: (a) Under the direct personal supervision of the Owner s Arborist, cleanly cut all damaged roots with a saw. Roots shall be covered with wet burlap for the time that they are exposed. Does not use root seals. The arborist must, within five (5) calendar days of the completion of this work, certify in writing to the Division that this work was done in accordance with standards of the International Society of Arboriculture (ISA) and that American National Standards Institute (ANSI), and the City s Oak Tree Ordinance (Calabasas Municipal Code, Section 17.26) and the Guidelines. (b) Properly prune (according to the Western Chapter of the International Society for Arboriculture Standards (Appendix A) all broken branch stubs in those areas subject to encroachment by restoration grading equipment or personnel. Do not seal wounds. No new pruning is allowed other than repair of broken limbs. All cuts will be performed using sharp tools leaving no ragged or torn ends. The Plan must list all proposed pruning on a tree-by-tree basis. This work must be completed under the direct personal supervision of the Owner s Arborist. The arborist must, within five (5) calendar days of the completion of this work, certify in writing to the Division that this work was done in accordance with standards of the ISA and the ANSI, and

5 the City s Oak Tree Ordinance (Calabasas Municipal Code, Section 17.26) and the Guidelines. (c) Owner shall repair the wound wood margins (the outer extent of damaged outer bark, inner bark, cambium, sapwood and heartwood) at each tree where mechanical or human inflicted damage has occurred. This work must be completed under the direct personal supervision of the Owner s Arborist. The arborist must, within five (5) calendar days of the completion of this work, certify in writing to the Division that this work was done in accordance with standards of the ISA and ANSI, and the City s Oak Tree Ordinance (Calabasas Municipal Code, Section 17.26) and the Guidelines. (d) Owner shall remove all debris within any open cavity and cover all open cavities with a fine wire mesh to keep organic matter outside of the wounds. Concrete or other similar materials shall not be used to seal or fill cavities. No holes shall be drilled to provide drainage of water traps. This work must be completed under the direct personal supervision of the Owner s Arborist. The arborist must, within five (5) calendar days of the completion of this work, certify in writing to the Division that this work was done in accordance with standards of the International Society of Arboriculture and that American National Standards Institute, the City s Oak Tree Ordinance (Calabasas Municipal Code, Section 17.26) and the Guidelines. (e) Any work near Tree Nos. 1-6 (McKinley & Associates Oak Tree Report, April 12, 2008) must be performed under the direct personal supervision of the Owner s Arborist. The arborist must, within five (5) calendar days of the completion of this work, certify in writing to the Division that this work was done in accordance with standards of the ISA and ANSI, and the City s Oak Tree Ordinance (Calabasas Municipal Code, Section 17.26) and the Guidelines. (f) Restore the areas beneath the Protected Zone of each tree to the original grade. Restoration shall return the 5

6 Protected Zone to a grade that insures positive drainage flow away from the root crown without ponding in any location within the drip line of each tree. This work must be completed under the direct personal supervision of the Owner s Arborist. The arborist must, within five (5) calendar days of the completion of this work, certify in writing to the Division that this work was done in accordance with standards of the ISA and ANSI, and the City s Oak Tree Ordinance (Calabasas Municipal Code, Section 17.26) and the Guidelines. (g) Any work that requires mechanical equipment must be described in detail and receive specific written approval of the Director of Community Development before equipment is brought to the premises and used. Grading work inside of the protected zone must only be by hand tools. (h) Using hand tools only, remove all rock, soil and debris from within the protected zone of the damaged oak trees. This work must be completed under the direct personal supervision of the Owner s Arborist. The arborist must, within five (5) calendar days of the completion of this work, certify in writing to the Division that this work was done in accordance with standards of the International Society of Arboriculture (ISA) and the American National Standards Institute (ANSI), and the City s Oak Tree Ordinance (Calabasas Municipal Code, Section 17.26) and the Guidelines. (i) After clearing the ground area within the protected zone of all damaged oaks, place an approved organic mulch cover the ground that is at least 3 deep. This work must be completed under the direct personal supervision of the Owner s Arborist. The Arborist must, within five (5) calendar days of the completion of this work, certify in writing to the Division that this work was done in accordance with standards of the International Society of Arboriculture (ISA) and that American National Standards Institute, (ANSI) and the City s Oak Tree Ordinance (Calabasas Municipal Code, Section 17.26) and the Guidelines. 6

7 (j) Per the City s Oak Tree Consultant s recommendation s; Owner shall remove accumulated annual weed growth beneath the protected zone of each of the 36 oak trees. This work must be completed under the direct personal supervision of the Owner s Arborist. The arborist must, within five (5) calendar days of the completion of this work, certify in writing to the Division that this work was done in accordance with standards of the ISA and ANSI, and the City s Oak Tree Ordinance (Calabasas Municipal Code, Section G(6)) and the Guidelines. Weed Abatement Plan: The Los Angeles County Fire Department, Fire Prevention Bureau requires yearly weed abatement of the properties owned by Ken, LLC, Kavoos Ahankoob. In the past, the required weed abatement was completed without benefit of an oak tree permit; consequently, the machinery and personnel employed to accomplish the fire prevention measures have illegally encroached upon the Protected Zones of the oak trees on the properties. In order to avoid this situation in the future, the Owner must obtain the necessary oak tree permits prior to any weed abatement activities and also implement the following measures in order to avoid illegal encroachment into the Protected Zones of the thirty-six (36) oak trees. 2.3 In order to avoid encroachment into the Protected Zone by the Weed Abatement Contractor and avoid repeated damage to the oak trees, Owner shall drive a one inch diameter pipe or rebar at least twelve (12 ) inches into competent soil at the outer edge of the Protected Zone [as defined by the Guidelines] of the thirty-six (36) oak trees. Eight (8) pipes shall be placed around each tree, extending two (2 ) feet above the natural grade. The eight (8) pipes shall be installed at eight compass directions (N, S, E, W, NE, SE, SW, and NW).Each of the exposed ends of the stakes are to be painted red. 2.4 After obtaining the proper oak tree permit allowing for weed abatement within the protected zone of the thirty-six (36) oak trees, the Owner shall notify the Weed Abatement Contractor of the presence of the markers and that any weed abatement work within the perimeter of the markers (The Protected Zone) shall be accomplished using hand tools only. 7

8 Monitoring Program 2.5 The Owner shall notify the Weed Abatement Contractor, in writing, that the oak trees located upon his/her property are protected by the City of Calabasas Oak Tree Ordinance. A copy of the notification letter given to the Weed Abatement Contractor must be submitted to the City of Calabasas Community Development Department within three (3) calendar days of contractor notification. A condition of approval for the oak tree permit applied for by Ken, LLC, Kavoos Ahankoob shall be the implementation of a monitoring program for a period of five (5) years. The purpose of this monitoring program will be to ensure that the above conditions 2.1 through 2.5 are being strictly adhered to and to make quantitative and qualitative observations that are useful in identifying stress-related responses of oak trees. Monitoring activities shall be performed in accordance with the procedures adopted in the Guidelines [Definitions]. 2.6 Beginning on April 13, 2009 and extending to April 30, 2014 the site shall be monitored, making quantitative and qualitative measurements, including but not limited to, the vigor and tree health specified in the Guidelines [definitions]. The monitoring shall be carried out by the Owner s Oak Tree consultant or his/her successor. 2.7 A written yearly update report shall be presented to the City. The report shall encompass all of the physical aspects of tree health for the thirty-six (36) impacted trees. The report shall also certify that annual weed abatement has been successful completed without new injury being inflicted to any tree present on the site. Additionally, there shall be a section contained within the report that certifies that all of the conditions stipulated in the Remediation Plan and Weed Abatement Plan have been strictly adhered to. The report will be subject to review and inspection and verification by the City and the City s Oak Tree Consultant. 2.8 At the completion of the five (5) year period, the Owner s Oak Tree Consultant shall certify that to the best of his/her knowledge and control, all of the prescribed requirements of the oak tree permit approved in File No have been met. 8

9 Section 3: PRC VALUATION AND SECURITY REQUIRED Considering the damage inflicted on thirty (30) of the thirty-six (36) encroached upon Protected Zones, it is reasonable to assume that one (1) of the damaged trees may ultimately succumb to the effects of the damages caused by the illegal encroachment. Using this assumption, the Owner shall be required, (Guidelines [Section V (D)]), to post a refundable security deposit in an amount equal to the cost of the replacement tree[s] and canopy. The dollar deposit shall be determined using the PRC method of determination as outlined in Appendix B [of the guidelines]. Appendix A stipulates that the City has determined that all oaks have a species value of 100%; therefore, no adjustment to the total PRC value can be made. Finally, Section XI (D) of the Guidelines states that the replacement [costs] shall be based on the PRC value or the actual replacement cost, whichever is higher, plus the cost for planting and maintaining the replacement trees. To provide an accurate example of a tree that may succumb to the cumulative effects of damages caused by illegal encroachment, we have chosen tree number 36 (McKinley and Associates, Oak Tree Report). Tree number 36 has suffered 100% encroachment into the Protected Zone with mounds of excavation spoils still in place within the drip line as well as broken branches that were caused by mechanical equipment collisions. PRC Value Calculations (Appendix B within the Oak Tree Preservation and Protection Guidelines): Tree No. 36: 26 diameter at breast height (DBH), breast height =4.5 Formula: $4,600 + $2,700(DBH-7) Calculation of Base Value: $4,600+$2,700(26-7 ) = $55,900 to purchase replacement tree. Taxes, Delivery, Travel Permits to Site, Installation and Guarantees; Estimated to be: $35,000. TOTAL REFUNDABLE SECURITY FOR REPLACEMENT TO BE TENDERED PRIOR TO ISSUANCE OF OAK TREE PERMIT $90, Since the total replacement cost is higher than the PRC value, the Section XI. D of the Guidelines requires that the higher amount be collected. 9

10 Section 4: Security Fees and Associated Costs to be submitted By Applicant Calabasas Municipal Code, Section (G) (10) stipulates that The City may require adequate security to ensure performance, correct construction procedures, reforestation, monitoring and maintenance, in amount to be determined by the City. The following fee schedule and breakdown has been calculated employing current rates charged by my firm and our best estimated based upon our extensive experience with work of this nature. The owner shall deposit security to ensure that all remediation, weed abatement and monitoring stipulated in section 2 is completed: 1. Preparation of Work Procedures Plan $ 1, Grading Repair to Oak Trees $10, Placement of Markers (36 trees) $ 3, Repair of broken branches and wound margins $ 1, Weed Removal and 3 organic mulch at 36 trees (@$360.00) $12, Monitoring by Oak Tree Consultant-year 1 $ 2, TOTAL.. $31, TOTAL SECURITY TO BE POSTED BY OWNER TO ENSURE PERFORMANCE OF ALL CONDITIONS IN RETROACTIVE OAK TREE PERMIT. TO BE DEPOSITED PRIOR TO ISSUANCE OF RETROACTIVE OAK TREE PERMIT. $31, The Owner shall deposit funds, on April 10 for the years 2010 through 2014, to a recoverable account, administered by the Community Development Department, to ensure payment for: 1. On site monitoring by Oak Tree consultant $1, Weed abatement at 36 trees (@$100.00) $3, Estimated City Oak Tree Consultant costs $ Estimated City Staff Costs $ Total. $6, TOTAL SECURITY TO BE POSTED BY OWNER TO ENSURE PERFORMANCE OF ALL CONDITIONS IN RETROACTIVE OAK TREE PERMIT. TO BE DEPOSITED ON APRIL 10 YEAR 2-5 ( ). 10

11 $6, The Owner shall deposit funds to a recoverable account, administered by the Community Development Department, to ensure payment for: Summary: 1. All costs incurred by the City relating to management and monitoring of the conditions imposed as part of the approval of this permit. Estimated yearly cost: :$1, All costs of the City s Oak Tree Consultant relating to management and monitoring the conditions imposed as part of the approval of this permit. EST: $1,000.00/yr. TOTAL RECOVERABLE FEES TO BE DEPOSITED EACH YEAR ON APRIL 10, 2009 $2, The Owner will be required to restore the 36 illegally encroached upon oak tree Protected Zones to the conditions existing prior to illegal grading. The preceding conditions will serve to accomplish that goal. The calculations have been completed according to the requirements of the Guidelines and The Calabasas Municipal Code, Section I recommend approval of this Retroactive Oak Tree Permit with all of the preceding terms and conditions based on the following findings: (E) (3) The condition or location of the oak tree or scrub oak habitat requires altering to maintain or aid its health, balance or structure. AND (E) (5)Removal or altering the oak tree(s) will have a minimal impact on the total hardwood canopy with special emphasis on associated tree growth and their natural regeneration, wildlife habitat and heritage oak trees. Respectfully submitted, James Dean, A.S.L.A., I.S.A. Landscape Architect 11

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