2.1 Equipment. All equipment to be used for trimming and emergency work and all work to be performed shall be in full compliance with the most current revision of the ANSI Z-133.1. The Contractor shall not allow any person to use shoes with spikes, spurs, climbing irons or any other footwear which may cause injury to the trees being trimmed under the terms of this agreement. 2.2 Pruning. Standard pruning shall be performed in accordance with standards established by the National Arborist Association which are published as ANSI A300 Part 1 Pruning Standard and the ISA’s Best Management Practices: Tree Pruning, as amended from time to time, which includes the removal of all objectionable branches otherwise described as dead, dying, diseased, interfering (within 8-feet of manmade structures), objectionable branches (V crotches/double leaders), suckers/water sprouts and weak branches. Objectionable branches lying inside and beyond the commonly described leaf area shall be removed from the main trunks and limbs. In the case of American elm, trees are to be trimmed so a “cathedral arch” effect is achieved. Crown Cleaning, Crown Thinning and Crown Raising, which involves removal of dead, dying, diseased, crowded, weakly attached, low vigor branches, one inch in diameter and larger, major interfering limbs and sucker growth. All work shall be completed in accordance with the following requirements: A. Collar cuts shall be made to promote health under normal conditions. “Flush” cuts to the main stem behind the branch collar, which leave oval exposed wounds, shall not be made. All improperly healed scars and areas where callused growth is not established are to be traced unless otherwise directed. Cuts shall be made such that all wound sides are even edged and do not leave “dog ear” ridges on one side or another. 18 B. Limbs larger than one inch in diameter shall be precut (undercut) to prevent splitting/tearing. C. Branches larger than 3½ inches in diameter shall be lowered to the ground through the use of ropes or other mechanical devices. D. At least one of all crossed or rubbing branches shall be removed to the extent possible. This removal shall not leave large holes in the general appearance of the tree. E. Pruning shall be done in order to maintain a tree-like form typical of the species being trimmed. F. Limbs shall be removed which overhang houses so as to provide a minimum of ten feet of clearance between the house and remaining limbs. Exceptions to this requirement may be made when the removal of a sound limb will greatly detract from the overall appearance of the tree. In those cases where determinations cannot be easily made, the DIRECTOR or his designee shall be consulted. G. All suckers and water sprouts shall be removed from the main laterals. To remove one branch of all structurally weak “(V)” crotches occurring along the main trunk or developing within the tree crown, particularly in smaller trees, special attention shall be given to the effect removal of such branches will have on the ultimate form of the tree. H. Tree-wound dressing will not be used. All tools used on a tree suspected of being infected with a contagious disease shall be thoroughly disinfected before being used on another tree.
