Laserfiche WebLink
David L. Bobby,Re risrered Consulting Arhorisi"' July 8, 2013 <br /> proximity to a tree's trunk would dictate which of the following installation methods <br /> can offer sufficient mitigation: mechanically excavating, hand-digging, a pneumatic air <br /> device (such as an Air-Spade R), or directional boring. <br /> 8. The proposed landscape design should conform to the following additional guidelines: <br /> a. Plant material installed beneath tree canopies should be at least 36 inches or more <br /> from their trunks. <br /> b. Irrigation should not be sprayed within 12 inches from the trees'trunks. <br /> c. Irrigation and lighting (including wiring and controllers) installed within a TPZ <br /> shall be in a radial direction to a tree's trunk. If this is not possible, the work may <br /> need to be performed using a pneumatic air device (such as an Air-Spad?) to <br /> avoid unnecessary root damage. Any Netafim tubing used should be placed on <br /> grade, and header lines installed in a radial direction to a trunk. <br /> d. Valve boxes should be established beyond TPZs. <br /> e. Ground cover beneath canopies should be comprised of a three-to four-inch layer <br /> of coarse wood chips or other high-quality mulch (gorilla hair, bark or rock, <br /> stone, gravel, black plastic or other synthetic ground cover should be avoided). <br /> Mulch should not be placed against the trees' trunks. <br /> f. Tilling, ripping, compaction and fine grading within TPZs should be avoided. <br /> g. Bender board or other edging material proposed beneath the canopies should be <br /> established on top of existing soil grade (such as by using vertical stakes). <br /> 9. Tree protective fencing shall be installed prior to any demolition and construction for <br /> the purpose of restricting access inside the TPZs of trees being retained around the <br /> existing building. A few weeks prior to demolition, I (hereinafter the "project <br /> arborist") should be retained to meet with the contractor to identify those locations. <br /> The fencing should consist of five- to six-foot high chain link mounted on eight-foot <br /> tall, 1 and 7/8-inch diameter galvanized steel posts that are driven into the ground 24 <br /> inches deep, and reasonably spaced apart to provide support. It should be established <br /> no farther than 12 inches from a curb, pathway and existing/proposed driveway edges, <br /> and remain intact and maintained throughout construction. <br /> 3192 Santa Rita Road, Pleasanton Page 6 of 10 <br /> Mr.Joe Nguyen,AS!Consullmg <br />