2_Exhibits A, C & D - Laserfiche WebLink

Updated Arborist Report HortScience, Inc. 4112 Foothill Rd., October 29, 2018 Page 4 Our goal is to identify trees that have the potential for long-term health, structural stability and longevity. Evaluation of suitability for preservation considers several factors: Tree health Healthy, vigorous trees are better able to tolerate impacts such as root injury, demolition of existing structures, changes in soil grade and moisture, and soil compaction than are non-vigorous trees. • Structural integrity Trees with significant amounts of wood decay and other structural defects that cannot be corrected are likely to fail. Such trees should not be preserved in areas where damage to people or property is likely. An example of this would be valley oak#2 with its multiple branch failures. See oak pruning guidelines exhibit. • Species response There is a wide variation in the response of individual species to construction impacts and changes in the environment. In general, valley oak is moderately tolerant of site disturbance. • Tree age and longevity Old trees, while having significant emotional and aesthetic appeal, have limited physiological capacity to adjust to an altered environment. Young trees are better able to generate new tissue and respond to change. • Invasiveness Species that spread across a site and displace desired vegetation are not always appropriate for retention. This is particularly true when indigenous species are displaced. The California Invasive Plant Inventory Database (http://www.cal-ipc.org/paf/) lists species identified as being invasive. Pleasanton is part of the Central West Floristic Province. None of the trees evaluated at the site are listed as invasive. Each tree was rated for suitability for preservation based upon its age, health, structural condition and ability to safely coexist within a development environment. Table 1 provides a summary of suitability ratings. Suitability ratings for individual trees are provided in the Tree Assessment Forms(see exhibits). We consider trees with good suitability for preservation to be the best candidates for preservation. We do not recommend retention of trees with low suitability for preservation in areas where people or property will be present. Retention of trees with moderate suitability for preservation depends upon the intensity of proposed site changes. Table 1: Tree suitability for preservation 4112 Foothill Blvd., Pleasanton, CA High These are trees with good health and structural stability that have the potential for longevity at the site. None trees were of high suitability for preservation. Moderate Trees in this category have fair health and/or structural defects that may be abated with treatment. These trees require more intense management and monitoring, and may have shorter life-spans than those in the"high" category. Two trees evaluated at the site were included in this category. Tag# Species Diameter 3 Valley oak 36 4 Valley oak 34 that are undesirable for landscapes, and generally are unsuited for use areas. (i.e. root pruning, trimming, setting up tree protection, etc.). The bond or security may be released early with a certification letter by the arborist confirming he/she was present during said tree work and work was performed in accordance with the arborist's recommendations. (PROJECT SPECIFIC CONDITION) P18-0109 Planning Commission Page 12 of 13 ed units. (PROJECT SPECIFIC CONDITION) P18-0109 Planning Commission Page 4 of 13