Laserfiche WebLink
In the case of the situation at Glenwood Terrace, the method has been <br />modified and the trees assessed were based on their size and location and <br />proximity to residences in addition to the presence of structural defects or <br />weakness. Trees of a similar size, with appreciable defects, located in striking <br />distance of the residences are given the same rating. Trees, further from the <br />structures, that would cause the failure of adjacent trees by direct impact are also <br />included. <br />Probability of Failure (1-5 points) <br />1. Low <br />2. Moderate <br />3. Moderately High <br />4. High <br />5. Extreme <br />The Probability of Failure rating represents an assessment of the condition <br />of the tree and the likelihood of failure during ordinary conditions and predicable <br />extraordinary conditions such as prevalent local storm conditions. In the case of <br />the trees at Glenwood Terrace predictable failure is due to a combination of <br />injury, decline, or defect. The trees with a high probability of failure are also <br />located on leeward edge of the stand; this location increases the likelihood of <br />wind damage and tree failure. <br />Size of Part (1-3 points) <br />The size rating is based on the diameter of the part. <br />1. Up to 4" <br />2. Between 4" to 20" <br />3. Greater than 20" <br />Target (1-4 points) <br />The target is rated on use and occupancy. The Target ratings are shown <br />with an example. <br />1. Occasional use (trails] <br />2. Intermittent use [picnic/parking areas] <br />Villas at Glenwood Terrace Tree Risk Assessment Robert W. Williams Consulting Arborist 7 <br />