16.50.100 Protection of trees before, during and after development.
A. All trees proposed for retention, supplemental tree plantings, and trees on adjacent property shall be protected before and during site development and construction through adherence to the following requirements:
1. Approved tree protection areas shall be designated in the field prior to the initiation of any clearing or grading per tree preservation plan established by a certified arborist. Tree protection areas shall remain in place through site development until project completion, or earlier with prior authorization by the planning director.
2. A tree protection area shall be designed to protect each tree or tree stand during site development and construction. The tree protection areas shall conform to the approved tree preservation pan.
3. Ideally, tree protection areas should extend to the drip line of the tree plus six feet. However, in many instances, this will not be possible due to site constraints. Tree protection areas shall be as large as feasible given site constraints and the nature of the project.
4. Tree protection areas shall be clearly shown on all applicable site development, preliminary plats, and construction drawings.
5. Tree protection areas shall be designated through the following minimum standards:
a. Chain link or other type of sturdy construction fencing attached to posts set in the ground a minimum of twelve inches and spaced no more than ten feet apart; and
b. Colored tape, ribbon, and other identification tags attached to protected trees.
6. Methods to provide additional protection for tree roots include:
a. Placing layers of protective mulch, six inches — two feet deep, over tree roots to help avoid soil compaction over roots that may be subject to nearby equipment use. Once construction is complete, excess mulch shall be removed leaving a maximum of two inches mulch cover over pre-existing grade. Then soil should be aerated by drilling holes.
b. Tunneling under root systems or circumventing the roots instead of cutting across them.
c. No toxic chemicals shall be used in tree protection areas.
7. No clearing, grading, filling, operating of heavy equipment, trenching, or other development activities shall occur within tree protection areas. Tree protection areas may only be modified or temporarily relocated with the prior written approval of the planning director.
8. The planning director may approve the use of alternate tree protection techniques if the above standards would create an undue hardship upon the applicant (such as designating buffer boundaries for large sites over an acre) and if the trees will be protected to an equal or greater degree than provided by this chapter. (Ord. 2756 Att. F, 2006)