(a) Construction Site Precautions. The following protective techniques shall be
followed during construction activity which may impact a Monarch Tree or trees on public property:
(1) Protect branch and trunk from equipment:
A. Fence vulnerable trees.
B. Move soil adjacent to trees by hand.
(2) Prune carefully for vertical clearance:
A. Prune to minimum height required before construction.
B. Dress all significant pruning wounds.
(3) Prevent injury from felling other trees:
A. Fell trees away from protected trees.
B. Use control cables if fall is not predictable.
(4) Avoid root damage during stripping of organic surface soil:
A. Avoid stripping of topsoil around trees in Critical Root Zone.
B. Cut woody vegetation around trees at ground level - do not pull out by equipment.
(5) Minimize root damage during excavation for foundations:
A. Excavate by hand near major roots.
B. Prune roots by cutting individually.
(6) Avoid injurious soil compaction by keeping storage and traffic out of Critical Root Zone.
(7) Prevent spills or waste disposal of paint, oil, fuel and other soil contaminants:
A. Prohibit disposal in Critical Root Zone.
B. Require immediate clean-up of accidental spills.
(8) Control concrete washout:
A. Designate wash-out area away from trees.
B. Avoid runoff of washout to forested areas.
(9) Control soil herbicides applied under sidewalk:
A. Use herbicides safe for use around trees.
B. Do not exceed recommended concentrations.
(10) Maintain surface drainage away from trees:
A. Where grades are modified, direct water away from trees.
B. Do not permit ponding in Critical Root Zone.
(11) Control trenching for utilities, drainage:
A. Coordinate trench locations with installation contractors.
B. Consolidate utility trenches.
C. Curve trenches if necessary.
D. Tunnel under roots larger than one inch in diameter when feasible.
(12) Control grading and scarifying operations:
A. Excavate no more than six inches below finish grade.
B. Add topsoil to achieve finish grade.
(13) Minimize thinning or removing of undergrowth:
A. Save clusters of trees when working with species which function poorly in the open or as singles.
B. As much as possible, save existing undergrowth.
(14) Protect from damage:
A. Do not permit construction or recreational fires within 100 feet of protected trees.
B. Do not permit razing of buildings by fire if within 100 feet; of protected trees.
(b) Authorized Types of Pruning on Monarch Trees And Trees on Public Property. Only the following types of pruning may be performed on Monarch trees and trees on
public property:
(1) "Medium Prune".
A. Description of "Medium Pruning". This operation of tree pruning shall consist of the total removal of those dead or living branches as may menace the future health, strength and attractiveness of the tree.
B. Specifications for "Medium Prune".
1. Properly remove all dead and dying branches of one fourth inch and over in diameter.
2. Remove all broken branches or any loose branches lodged in the tree.
3. Remove all dead and live stubs of previously broken or poorly cut branches.
4. Remove any live branches which interface with the tree's structural strength and healthful development, which will include the following:
a. Branches that rub and abrade a more important branch.
b. Branches of weak structure that are not important to the framework of the tree.
c. Branches that, if allowed to grow, would wedge apart the junction if more important branches.
d. Branches with twigs and foliage obstructing the development of more important branches.
e. Branches forming multiple leaders in a single leader type tree.
f. Branches near the end of a limb which will produce more weight or offer more resistance to wind that the limb is likely to support.
g. Undesirable sucker and sprout growths.
h. Selective removal to one or more developing leaders where multiple branch growth exists near the end of broken or stubbed limbs.
i. Removal of branches that project too far outward beyond an otherwise symmetrical form.
j. Removal or severance of any exposed roots that restrict or act in a girdling manner and prevent proper expansion and growth of other major roots, or restrict the base of the tree trunk.
C. All final cuts shall be made just outside the branch collar. Extremely deep cuts which produce excessively wide wounds or weaken the tree shall not be made.
(2) "Minimum or Safety Prune".
A. Description of "Minimum or Safety Prune". This operation of tree trimming shall consist of the minimum performance necessary to correct one or more extreme and undesirable conditions existing within a tree which may be hazardous to persons or property.
B. Specifications for "Minimum or Safety Prune".
1. Remove all dead and dying branches two inches or more in diameter.
2. Remove all broken or loose branches two inches or more in diameter.
3. Reduce the length of branches which extend excessively beyond the perimeter of an otherwise symmetrical form.
4. Cut back ends of branches and reduce weight of bunches where excessive breakage of supporting limbs appears likely. Do not remove live, healthy branches in excess of six inches in diameter without consent of the Tree Authority or its designee.
(3) "Head Back Prune".
A. Description of "Head Back Prune". This operation shall consist of reducing the height and/or spread of a tree by not more than one- third and shall only be applied to trees when such work is necessary to control extended growth which may endanger overhead utility lines or interfere with adjacent structures.
B. Specifications of "Head Back Prune".
1. This form of pruning trees shall be done by means of a method called "drop crotching" which serves to shorten branch structure and thereby limits the extent of the foliage canopy to a natural appearing margin. This action consists of removing perimeter branches at their lower junction with shorter side branches.
2. No cuts on living branches shall be made in excess of six inches in diameter without first securing specific consent of the City Forester (or his appointed authority).
3. Extended perimeter branches shall be properly cut at their junction with lower branches having a basal diameter of at least one-third of the diameter of the cut so affected.
4. The remaining lower branches shall be retained intact to form a reduced foliage perimeter at a specific height and/or spread.
5. This technique of tree pruning shall be applied only when larger growing trees endanger overhead utility lines or where excessive growth of trees interferes with adjacent structures or otherwise creates a specific hazard to persons or property.
6. "Head Back Prune" should not be attempted or used if the metabolism of a tree would be seriously unbalanced by the use of this technique or where the structure of the tree would be weakened by such action. Trees not repairable shall be removed rather than pruned with this method.
(4) "Spot Prune".
A. Description of "Spot Prune". This operation of tree pruning shall consist of the removal of one or more branches localized in a particular area of the crown of a tree.
B. Specifications for "Spot Prune".
1. Trees shall be pruned in such a manner as to prevent bunch and foliage interference with requirements of safe public passage. Over street clearance shall be kept to a minimum of fourteen feet above the paved surface of the street and eight feet over the surface of the public sidewalk or pedestrian way.
2. Sprout or sucker growth shall be removed to a minimum height of eight feet above the ground level. Exceptions are allowed for young trees which would be irreparably damaged by such trimming action.
3. Individual or scattered dead or broken limbs shall be promptly and properly removed without the necessity of performing other work not immediately urgent for protection of the public or property, or the health of the tree.
(c) Supplementary Pruning Specifications for Monarch Trees. The following additional requirements shall apply to the pruning of Monarch trees:
(1) No tree shall be cut back in such a manner that its health will be impaired. An exception to this may occur in the removal or emergency relief of an immediate danger to persons or property.
(2) When tree pruning cuts are made to a side branch, such remaining branch must possess a basal thickness of at least one-third of the diameter of the wound so affected. Such cuts shall be considered proper only when such remaining branch is vigorous enough to maintain adequate foliage to produce woody growth capable of healing the cut within a reasonable period of time.
(3) All final tree pruning cuts shall be made in such a manner as to favor the earliest possible covering of the wood by natural callus growth. Excessively deep flush cuts which produce large wounds or weaken the tree at the cut shall not be made. Tree pruning cuts should be made just outside the branch collar.
(4) Tree branches shall be removed and controlled in such a manner as not to cause damage to other parts of the tree or to other plants or property.
(5) All tools used on a tree known to contain an infectious tree disease shall be properly disinfected immediately after completing work in such a tree.
(6) Maples, birches and walnut trees shall be pruned only when in leaf except where conditions hazardous to the public or property are involved.
(7) All cutting tools and saws used in making tree pruning cuts shall be kept sharpened adequately to result in final cuts with a smooth surface and secure bark remaining adjacent thereto.
(8) Whenever pruning cuts are to be made while removing branches too large to hold securely in one hand during the cutting operation, the branches shall be cut off first one to two feet beyond the intended final cut. Then the final cut shall be made in a manner to prevent unnecessary tearing back of bark and wood.
(9) Any cutting of tree roots, other than when in the process of tree removal, shall give due consideration to the future welfare of the tree. Proper action shall be taken, utilizing the latest scientific techniques, to treat resulting wounds to prevent entry of decay organisms.
(10) The use of climbing spurs or spike shoes in the act of pruning trees is prohibited.
(11) Under no condition shall it be considered proper to leave any severed or partially cut branches in the upper portion of any tree being worked on after the tree workers leave the scene of the operation.
(12) Public trees or utility poles shall not be used as an anchor for winch trunks in the process of removing other trees.
(13) When removing a tree, the act of cutting tree roots and then leaving the work scene with a standing tree having little or no support is prohibited.
(Ord. 95-61. Passed 11-2-95.)