A. Pruning:
1. All pruning of city trees shall conform to National Arborist Association standards. Pruning should be done to promote general health and vigor of the tree.
2. All trees shall be maintained as not to endanger, interfere or conflict with public safety.
3. Under no circumstances shall a city owned tree be "topped" except under special circumstances to be determined by the public works department. "Topping" is the practice of severely pruning a tree, disregarding nodes and crotches, to drastically reduce the height of a tree.
4. All medium to large trees shall be pruned, to allow vehicular and pedestrian traffic unobstructed passage, to a height no less than eight feet (8') above sidewalks and sixteen feet (16') above streets.
5. All cuts shall be made with a saw or pruner and only at nodes or crotches with the method known as drop crotch pruning. Cuts shall be made without cutting into the branch collar. All cuts shall be made at a forty five degree (45°) angle from the branch bark ridge. Branches too large to be supported by one hand shall be precut for safety and to avoid the splitting or tearing of the bark. Large limbs shall be lowered safely in a controlled manner with ropes and other equipment. No stubs or "dog ears" shall be left.
6. Spurs or climbing irons shall not be used for pruning trees.
7. Pruning of any type of parkway trees shall only be allowed from November through April. Between May through October, pruning parkway trees is allowed only in emergency situations or if a hazardous condition exists, or as directed by the superintendent of streets.
8. After working on a diseased tree, all pruning equipment must be disinfected before working on another tree.
9. Upon the completion of work performed on city trees, all branches, twigs, leaves, chips and larger portions of the tree shall be promptly removed and properly disposed of by those performing the work.
B. Spraying: No spraying of any city tree will be allowed without prior approval of the public works department.
1. Precautions shall be undertaken to inform, warn and protect the public before spray applications of pesticides and other potentially hazardous chemicals begin. Local conditions such as wind and temperature shall be taken into account before spraying. Drift potential shall be examined in relation to the proximity to playgrounds, schools and high traffic density areas before any spraying is performed.
2. Spraying shall only be performed by certified commercial pesticide applicators and in accordance with accepted arboricultural standards and all state and federal laws governing such work. The applicator shall have read and understood label information of the chemicals being used.
3. Spraying shall only be done for specific insects or diseases with the proper equipment, in the necessary strength, and applied at the proper time to ensure control.
4. Dormant oils shall only be applied to specific species. They shall only be applied when the air temperature will be above forty degrees (40°) for a period of at least twenty four (24) hours after spraying.
5. All spray equipment should be kept clean and in good working order. Spray machines should give uniform coverage. Tanks and other equipment shall be washed out and drained in approved drainage areas.
6. Ineffectual control, damage, injury or death to plants, animals or persons resulting from the use of spray materials exceeding the limitations of the manufacturer's guarantee shall be considered the responsibility of the licensed operator.
C. Fertilization: The fertilization of city trees shall be in accordance with accepted arboricultural standards. Methods of applications for fertilizers shall be determined by the public works department.
D. Cavities: The treatment of cavities shall be in accordance with accepted arboricultural standards. The method for treatment of cavities shall be determined by the city arborist.
E. Cabling And Bracing To Be Determined By The Public Works Department:
1. Cabling and bracing methods shall be in accordance with the National Arborist Association or accepted arboricultural standards.
2. Cables should generally be placed two-thirds (2/3) the distance between the crotch and branch ends. Rust resistant cables with a minimum of common grade seven (7) strand cable shall be used. A thimble shall be used at the end of the cable. The cable ends shall be spliced or properly wrapped. Lag hooks or eyebolts with a washer and bolt shall be used to anchor the cable. Under no circumstances is a cable to be wrapped around a branch.
3. Bracing is not to be used as a substitute for cabling but rather in conjunction with cables. When using braces they shall be made of rust resistant steel rods. All washers and bolts used with braces shall also be made of rust resistant steel. (Ord. 08-11, 8-4-2008)