(A) General requirements.
(1) The trees shall be pruned by removal of all dead, diseased, broken and crossing branches.
(2) Live branches shall be removed to maintain the natural shape and appearance of the trees. Mutilation and loss of characteristic shape of the trees shall be prohibited.
(3) Selective removal of complete limb or limbs shall be performed rather than excessive clipping with pruners i.e., a “hedge trimming” effect shall be avoided.
(4) Saw or pruner cuts shall be flush with the parent limbs or trunk of the tree.
(5) Limbs shall be precut, using a three-cut technique to prevent splitting or stripping of bark. Ropes shall be used for lowering cut branches where necessary to prevent damage to trees, conductors, fences, cars and other property.
(6) No “hangers” shall be left in the trees after pruning is completed.
(7) All old stubs shall be removed and treated. All old scars shall be inspected and if not healing properly, shall be retraced and treated.
(8) The lower branches of the tree shall be raised (where the top is sufficient to maintain balanced life) to a height of 14 feet above the traveled portion of the street at the curb line and seven feet above the sidewalk and outlawn areas.
(9) Tools used to prune suspected or diseased trees shall be disinfected before being used on another tree.
(B) Pruning procedures and scope of work. Any tree large enough to support a trimmer shall be climbed and trimmed. It will not be deemed sufficient for the trimmer to remain on the ground and trim trees with a pruning pole unless agreed upon by the Director of Public Works.
(1) Light pruning. The removal of dead wood, suckers, crossed branches and stubs up to one-inch in diameter.
(2) Medium pruning. The work will include all of item 1 (light pruning) plus branches up to four inches in diameter. Wounds are to be treated with a tree paint containing napthamoleacitec acid.
(3) Heavy pruning. Work will include items 1 (light pruning) and 2 (medium pruning) above. Also include the removal of limbs over four inches in diameter. Items 1, 2, and 3 above will include topping (pollarding), trace and paint, treatment for girdling roots, installation of supporting cables and/or bolting and sectional cavity repair work when specifically requested by the Director of Public Works.
(4) Shaping. If in obtaining the desired shape, trees are rendered unsightly due to lack of symmetry, further pruning to restore their appearance shall be carried out. The extent of such shaping shall be governed by the location and type of tree, the nature of its surroundings, and the like. Full shaping will consist of:
(a) The removal or shortening by natural methods of branches in the crown of the tree. Sufficient growth must be left on a cut back branch to keep it alive and when possible the branch being shortened shall be cut back far enough to preserve the natural appearance of the tree.
(b) Side pruning shall not be so severe as to restrict the tree's ability to produce the food necessary for healthy growth. Top growth shall not be reduced a greater amount than that permissible for the species as listed below:
50%-Silver Maple, Willow, Poplar and other fast-growing varieties
40%-Basswood, Elm, Walnut, Ash
14-20%-Beech, Norway and Sugar Maples and other slow-growing species
(C) Pruning and utility wires.
(1) Any line clearing operation shall provide adequate clearance for all power and communications circuits, including primary service leads, as well as strain and anchor guys attached to the poles or structures of the line.
(2) Limbs under conductors. Limbs growing up into the conductors from the side of a tree shall be removed at the main trunk. If this appears impractical or inadvisable, the limbs shall be shortened to avoid whipping up into the line.
(3) Limbs parallel with conductors. Limbs growing out from the side of a tree, parallel with conductors, and could sway into the lines, shall be removed if practical, or shortened.
(4) Overhanging limbs. Limbs directly over the conductors shall be removed if practical; otherwise, they shall be shortened sufficiently to prevent their dropping in to the wires under the additional weight of snow or ice.
(5) Dead limbs. All dead limbs shall be removed.
(D) Hazardous trees.
(1) Reporting. Any person engaged in trimming or pruning who becomes aware of a tree of doubtful strength which could be dangerous to persons and property shall report it to the Director of Public Works. Such trees shall include those that are over mature, diseased, or showing signs of decay.
(2) Diagnosis. Trees of doubtful strength shall be bored at the base with a ½-inch auger to determine the amount of dead wood. At least three borings shall be made. Borings shall also be made in the wood surrounding doubtful areas in the trunk or main branches as may be indicated by exposed wood, frost cracks, bulges or sunken areas. These procedures shall be performed by the city.
(3) Test holes to be plugged. Test holes in all trees left standing following diagnosis shall be plugged with bark around the holes with a knife. The end of the dowel shall be flush with the wood and the wound treated with a tree wound dressing.
(Ord. 545, passed 3-6-78) Penalty, see § 99.99