Oak Tree Permit Number PL Review 4895 Las Virgenes Road, Calabasas, California

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1 DATE: December 29, 2017 TO: Mr. Michael Klein FROM: Ryan Gilmore, Arborist Subject: Oak Tree Permit Number PL Review 4895 Las Virgenes Road, Calabasas, California Dudek evaluated one coast live oak (Quercus agrifolia), Tree ID Tag OS1, and one valley oak (Quercus lobata) Tree ID Tag OS2 located within the Caltrans right-of-way (ROW) adjacent to the property of 4895 Las Virgenes Road on December This statement of facts summarizes the results of Dudek s review of the submitted permit application, site and field assessment, current and potential impact details, and provides recommendations for future tree management. APPLICANT BACKGROUND The property owner of 4895 Las Virgenes Road has requested approval to encroach within the driplines of two property adjacent native oaks consisting of a single coast live oak tree and valley oak tree. The two trees are located immediately adjacent to the site in the Caltrans ROW for the freeway on-ramp to the south of the property line. The property owner is proposing to encroach upon the protected zones of both trees to accommodate the construction of a Montessori Academy School. Proposed work within the driplines of the trees is as follows: demolition of parking lot, gutter, and curb, and the construction of a new reconfigured parking lot and outdoor play area with associated landscaping. The applicant s arborist report states that about 300 square feet of the protected zone of Tree #OS1 and 100 square feet of the protected zone of Tree #OS2 will experience some surface-level encroachment. Additionally, no canopy pruning is proposed or anticipated with implementation of the project. The first tree, tagged OS1, is a young single-stemmed coast live oak tree that has a history of dead-head pruning (where pruning cuts are improperly performed) and has grown entangled with the a chain-link fence. The second tree, tagged OS2 is a medium sized, single stemmed, valley oak that sits well within the Caltrans ROW. Both trees have a history of drought stress though both trees are showing signs of recovery.

2 Mr. Michael Klien Subject: Oak Tree Permit Number PL Review 4895 Las Virgenes Drive, Calabasas, California CITY REQUIREMENTS Trees subject to City permit requirements include those defined by Chapter C.3 of the City s Oak Tree Regulations Ordinance. It states that an oak tree permit shall be required to remove or alter oak trees, under certain circumstances: The most applicable circumstances for the two native oak trees located adjacent to the 4895 Las Virgenes Drive property are (item e): e. Replacement, modification or repair of existing improvements within the protected zone of an oak tree, as long as the tree is not impacted by the action. OBSERVATIONS Based on City-provided site and tree information, Dudek visited the property on December 18, The 4895 Las Virgenes Road site includes no regulated native oaks onsite. Adjacent to the property within the Caltrans ROW for the freeway on-ramp to the south, are two regulated native oak trees which were observed to have tree crowns over the subject property. The tree s protected zones encroach within the proposed construction footprint. The oak trees meet the requirements of protected trees as defined by Chapter on the Municipal Code. These two native oaks include the following key observations. Tree Observations Tree No. 1 (tagged OS1) is a young single-stemmed coast live oak tree that has experienced multiple flush cut branches to keep it from conflicting with an existing chain-link fence and to provide clearance for the existing parking lot. One of the old cuts is approximately two inches wide and six inches long (see photos). Furthermore, the oak has grown entangled with the fence. The fence completely bisects the lower trunk twice (see photos). The coast live oak tree is located along the southern property boundary, about three feet from curb face. The tree has a trunk diameter at standard height (DSH) of approximately six and a half inches. The tree is approximately 23-feet tall and has an estimated crown width of 12-feet across at its widest point. The tree exhibits good health and poor structure (primarily due to poor pruning history and being entwined with the chainlink fence), did not exhibit signs of root or soil problems, nor did it exhibit signs of disease or pest infestation. The entwined chain-link fence is restricting the growth of the tree and may affect its overall structure in the long-term future. Representative photographs are presented in Attachment 1. The tree exhibited signs of drought stress recovery due to the recent 5-yeat long statewide drought. It should be noted that at the time of the site visit, Caltrans was conducting ground disturbing work within the dripline of the tree, consisting of the removal of all vegetation December 2017

3 Mr. Michael Klien Subject: Oak Tree Permit Number PL Review 4895 Las Virgenes Drive, Calabasas, California around the oak tree with a backhoe loader. It is unknown what other activities are proposed to occur in the ROW. Tree No. 2 (tagged OS2) is a medium, single-stemmed valley oak tree located along the southern property boundary, about nine feet from curb face and behind the coast live oak, with a trunk diameter of thirteen inches DSH. The tree is approximately 30-feet tall and has an estimated crown width of 22-feet across at its widest point. The tree exhibits good health and fair structure. The tree did not exhibit signs of root or soil problems and did not exhibit signs of disease or pest infestation. Representative photographs are presented in Attachment 1. The tree exhibited signs of drought stress recovery due to the recent 5-year long statewide drought. It should be noted that at the time of the site visit, Caltrans was conducting ground disturbing work within the dripline of the tree. Ground disturbance work observed consisted of the removal of all vegetation around the oak tree with a backhoe loader. It is unknown what other activities are proposed to occur in the ROW. PROPOSED TREE IMPACTS The tree impacts, as discussed in this review, are based on the information provided to Dudek by the submitted application and on the results of Dudek s visual site evaluation on December 18, Tree No. 1 (tagged OS1) - The applicant has proposed to encroach within the protected zone (totaling 320 sq. ft.) of the tree to demo the existing parking lot, gutter, and curb, and the construction of a new reconfigured parking lot and outdoor play area with associated landscaping. Overall, approximately 300 square feet of the protected zone will experience some level of surface level disturbance. No tree crown reductions are proposed at this time. Tree No. 2 (tagged OS2) - The applicant has proposed to encroach within the protected zone (totaling 484 sq. ft.) of the tree to demo the existing parking lot, gutter, and curb, and the construction of a new reconfigured parking lot and outdoor play area with associated landscaping. Overall, approximately 100 square feet of the protected zone will experience some level of surface level disturbance. No tree crown reductions are proposed at this time.. RECOMMENDATIONS Based on the review of the permit application and site evaluation, Dudek recommends the following: December 2017

4 Mr. Michael Klien Subject: Oak Tree Permit Number PL Review 4895 Las Virgenes Drive, Calabasas, California 1. The Applicant shall utilize the City required tree protection measures as summarized within the submitted Arborist Report. Proper application of these mitigation measures under the guidance of an ISA Certified Arborist should reduce the soil surface level encroachments to a less than significant level. Discussion If the property owner and/or the tree contractor have any concerns regarding the direction provided in this recommendation, the City s contract arborist will be available to provide direction on-site. The arborist or other City staff may be conducting a post-construction tree evaluation to confirm that the health of the two oaks trees. If root pruning is necessary it should be performed under the supervision of an ISA Certified Arborist. No more than 25 percent of the roots should be removed at any one time. All pruning shall conform to American National Standards Institute (ANSI) A-300 standards. Should either of the trees need to be removed in the future due to circumstances listed under Chapter on the Municipal Code, an Oak Tree Permit will need to be submitted by the property owner. CONCLUSION In summary, Dudek evaluated one coast live oak tree and valley oak tree submitted under the Oak Tree Permit. The trees are located adjacent to the property at 4895 Las Virgenes Road within the adjacent Caltrans ROW. The trees were observed to be in generally good health with good to poor structures. The proposed surface level encroachment is not considered significant with the proper application of required City tree protection mitigation measures. Based on the review of the application and site evaluation it recommended that the permit be granted. If you have any questions or require any additional information, please call Noah Stamm at Sincerely, Ryan Gilmore, Calabasas Contract Arborist ISA-Certified Arborist WE AM Att: Attachment 1, Representative Site Photographs December 2017

5 ATTACHMENT 1 Representative Site Photographs

6 Attachment 1 - Oak Tree Permit Number PL Representative Site Photographs 1. Overview of both oaks, Tree OS1 on the left and Tree OS2, as viewed to the south. Note the curb, gutter, and parking lot to be removed. 2. Overview of Tree OS2 and Caltrans ROW with recently removed vegetation, as viewed to the south. Photographs were taken on December 18,

7 Attachment 1 - Oak Tree Permit Number PL Representative Site Photographs 3. Overview of Tree OS1 and entwined chain link fence. 4. Overview of Tree OS1 and entwined chain link fence. Photographs were taken on December 18,

8 Attachment 1 - Oak Tree Permit Number PL Representative Site Photographs 5. Overview of both trees with Caltrans conducting soil disturbance work within the ROW. 6. Overview of both trees with Caltrans conducting soil disturbance work within the ROW. Photographs were taken on December 18,