Specifications include, but are not limited to: a. All pruning shall follow the American National Standards Institute (ANSI) A300 (Part 1) - 2001 Pruning Standard and the International Society of Arboriculture’s (ISA) Best Management Practices: Tree Pruning (2002) for the purpose of crown cleaning, crown thinning, crown raising, and structure development. b. All pruning shall improve the appearance of the trees, maintaining the crown shape and symmetry typical of the species at its given size and age with an emphasis on the following: 1. Crown cleaning to remove all dead, dying, diseased, crowded, weakly attached and low-vigor branches greater than 1/2” in diameter. 2. Crown thinning to selectively remove and/or prune branches back to large laterals to increase light penetration and air movement through the crown. After crown thinning, trees and branches shall have foliage and mechanical stress evenly distributed along a branch and throughout the crown. Not more than one-fourth of foliage on mature trees shall be removed. 3. Crown raising to remove lower branches where practical (dependent on tree size) to obtain an eventual full foliage height clearance of fourteen (14) feet on the street side of the tree. All work shall always maintain the crown shape and symmetry typical of the species being pruned, and shall balance the tree evenly. This raising should also allow an eventual clearance over the pedestrian walk (or resident side of tree) of ten (10) feet. Pruning may include heading cuts on lower limbs or thinning cuts to lighten lower branch loads to achieve clearance if complete branch removal from the tree trunk is not practical. 4. Pruning for structure in young trees (those with diameters 0-12”) such that if a scaffold branch is large in diameter and competes with the leader, that this scaffold branch be headed back to a lateral and/or thinned to obtain a balanced crown shape overall. 5. Pruning to remove all interior crowding branches, and one of all crossed or rubbing branches where practical so the removal thereof will not leave large holes in the general form of the tree.