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Tree assessment. Hort Science, Inc. Bonde Ranch. City of Pleasanton. Page 6 The points in each category were added to obtain the overall risk ranking, with 3 being the minimum and 12 being the maximum value. Risk ranking =failure potential +size of defective part+target rating Among the trees assessed, the most likely failure included stem (13 trees), *branch (48), and the whole tree (4). Among potential targets were back yards , of residences (52), open space (8), N residential structure (3) and Hopkins Way , (2) 4-, Risk rankings of the surveyed trees r <` ' ranged from 3 to 8 (see enclosed Tree ,; > "fi;,, Risk Rankings). Sixty-one (61)trees , received rankings of 6 or lower. Blue • e gum#157 received a ranking of 7. Blue gums#141, 142 and 159 received ' rankings of 8 and comprised the 3 trees where a residence was the target(Photo - = • 5) _ ... , _ Photo 5. Looking north at blue gums _- #141 and 142 (red circle). The upper Y ` 14. crowns of these trees are bowed to the • south towards the nearby residence. Summary and Discussion This row of trees grew for many years with little or no management, save for the topping of selected trees. When the adjacent residences were constructed, the City initiated a program of pruning trees every few years at the property line. As a result, no large branches extend into back yards and over residences. Approximately half of the trees were in fair condition and another one-third were in poor condition. Nine(9) of the 65 trees were in good and excellent condition. Differences in condition were largely due to spacing between trees and history of care. Relative risk associated with the trees was low with 61 of 65 trees having a ranking of 6 or lower(on a scale from 3 to 12). The most common situation was a small diameter branches extending over the property line and back yard. Exceptions were several trees where branches could hit the residence should they fail. Under a normal management regime, trees with the highest ranking would be abated first, followed in order of decreasing ratings.