15 ATTACHMENT 9 - Laserfiche WebLink

~~ < , Dan Sarich HortScience, lnc. "~~ Sarich Property Tree Preservation `Page 2 The condition ratings were based on a visual assessment of tree health and structure. Ninety-nine of the trees (44%) were in good condition (rating category 4 or 5); 85 (38%) were in fair condition (rating category 3); 42 trees (19%) were in poor condition (rating category 1 or 2). Table 1: Tree Species and Condition Species Condition Total Common name Scientific name Good Moderate Poor 'California buckeye iAescu/us californica ;Silver dollar gum 'Eucalyptus polyanthamos 2 I 1. 3 ~ _M ~___ ~ Red iron bark :Eucalyptus sideroxylon ~ ~ ~ ~~ _ 1 1 ;Blue oak .____. _ Quercus douglasii i 95f _ 81 37~j 213 _ ~ :Valley oak Quercus lobata _~_~__. ~ ~ _ 2' ~ ._.._.._._..___.34 . 2~ ~ __ ~ `Yellow willow ~ _ _._ .__.___ ~ Salix a/ba 'vitellina' ~ 1 1 Total # Trees 99 85 42 226 Percent of population 44% 38% 1 9% 100% The generally good-to fair condition of the trees owes primarily to the trees being native to the site and thus well adapted to the climate and soil conditions present. Trees in poor condition suffering from age-related decline in health or had structural defects. No pests or diseases were observed on the site. Suitability for Preservation Before evaluating the impacts that will occur during development, it is important to consider the quality of the tree resource itself, and the potential for individual trees to function well over an extended length of time. Trees that are preserved on development sites must be carefully selected to make sure that they may survive construction impacts, adapt to a new environment and perform well in the landscape. Our goal is 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 poor branch attachments 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 could occur. ^ Species response . There is a wide variation in the response of individual species to construction impacts and changes in the environment. In our l experience, trees such as valley oak and blue oak are moderately J difficult to preserve. They rarely recover from injuries to the root system. In contrast, other species, such as coast live oak, are more tolerant of site disturbance. J L .~ ,