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Preliminary Arborist Report 536 St. John Street, Pleasanton June 20, 2016 Page 6 Preliminary Evaluation of Impacts and Recommendations Appropriate tree retention develops a practical match between the location and intensity of construction activities and the quality and health of trees. The Tree Assessment was the reference point for tree health and condition. I referred to the Site Plan created by MacKay & Somps to evaluate the impacts to trees from the proposed development. The plan proposes to construct 10 townhomes, a driveway, bioretention areas, and move the existing home to the northwestern corner. Due to the density of construction, tree preservation will be limited to street and off -site trees. Eight trees (3 Protected) will be removed to accomplish the planned construction (trees #44 -48, 50, 54 and 55) and trees #43 (Protected) and 52 should be removed because of their health (Table 3). The three off-site trees and one of the street trees should survive the impacts associated with site development (#49, 51, 53 and 56). Table 3: Preliminary tree disposition 536 St. John Street, Pleasanton Tag # 43 44 45 46 47 48 49 50 51 52 53 54 55 56 Species English walnut English walnut Valley oak English walnut Coast live oak English walnut English hawthorn Coast live oak Modesto ash Black locust African fern -pine Modesto ash Coast live oak Coast live oak Diameter 16 18 10 12,11 8,6,5 16 7 6 28 9 7 28 28 20,14 Disposition Remove Remove Remove Remove Remove Remove Potentially preserve Remove Potentially preserve Remove Potentially preserve Remove Remove Potentially preserve Two Protected trees in good health will be removed based on the current construction plans. Modesto ash #54 will have construction within a few feet of its trunk to build the driveway connecting the units with St. John Street. Coast live oak #55 would require pruning and root loss to construct unit 6 as well as the bioretention. I do not expect either tree to tolerate these impacts. If the design team is interested in preserving these trees, they need to be accurately located (including elevation) before I suggest design revisions. The three off-site trees should survive impacts that do not go beyond the property line. Modesto ash #51 should be able to survive impacts if development is kept 10 feet off the trunk. This Tree Protection Zone is described in the Tree Protection Guideline below. Pruning for clearance will likely be required to relocate the house.