(A) 
Replacement.
Any protected tree that is healthy and growing on a site, but is not preserved, must be replaced at the minimum rates shown in Table 4-9 for each type of tree (see example of how to inventory, identify, and calculate tree mitigation in Illustration 4-3).
(B) 
Replacement Trees To Be Used.
Any tree planted as a replacement tree to comply with provisions of this Article 4 must be approved by the Development Director or the Director’s designee.
(C) 
Replacement Trees To Be Used.
Any tree planted as a replacement tree to comply with provisions of this Article 4 must be approved by the Development Director or the Director’s designee.
(D) 
Lots or Tracts Two Acres in Size or Larger.
For a lot or tract that is two acres in size or larger, no one species of tree may constitute more than thirty percent (30%) of the replacement trees.
Table 4-9: Existing Trees - Replacement Ratios
Existing Tree Species
Replacement Ratio
Class 1 Trees
2:1 (2 caliper inches per 1 diameter inch)
Class 2 Trees
1:1 (1 caliper inch per 1 diameter inch)
Class 3 Trees
0.5:1 (1/2 caliper inch per 1 diameter inch)
Illustration 4-3 Example of Tree Inventory and Mitigation Calculation
4-Ill 4-3.tif
Example 1
Tree to be Removed
Total Caliper Inches to be Removed
Replacement Ratio
Replacement Caliper Inches Required
Live Oak
8.0 inches
1.0:1 (1 caliper inch per diameter inch)
8.0 inches
Live Oak
28.0 inches
2.0:1 (2 caliper inches per diameter inch)
56.0 inches
Arizona Ash
14.0 inches
0.5:1 (0.5 caliper inches per diameter inch)
7.0 inches
Subtotal
50.0 inches
 
71.0 inches
Example 2
Trees to be Removed
Total Caliper Inches to be Removed
Replacement Ratio
Replacement Caliper Inches Required
Mesquite
7.0 inches
0.5:1 (1/2 caliper inch per diameter inch)
3.5 inches
Hackberry
3.0 inches
N/A (non-protected tree)
0.0 inches
Cedar elm
12.0 inches
1.0:1 (1 caliper inch per diameter inch)
12.0 inches
Pecan
18.0 inches
1: 1 (1 caliper inches per diameter inch)
36.0 inches
Hackberry
4.0 inches
N/A (non-protected tree)
0.0 inches
Cottonwood
6.5 inches
0.5:1 (1/2 caliper inch per diameter inch)
3.25 inches
Subtotal
50.5 inches
 
54.75 inches
Other Tree Species (not listed in Table 4-1 or in Table 4-2)
Tree to be Removed
Total Caliper Inches to be Removed
Replacement Ratio
Replacement Caliper Inches Required
PD-1
4.0 inches
0.25:1 (1/4 caliper inch per caliper inch)
1.0 inch
PD-2
12.0 inches
0.25:1 (1/4 caliper inch per caliper inch)
3.0 inches
GT-1
8.0 inches
0.25:1 (1/4 caliper inch per caliper inch)
2.0 inches
Subtotal
24.0 inches
 
6.0 inches
TOTAL
124.5 inches
 
171.75 inches
(Ordinance 6773 adopted 5/19/15; Ordinance 7107, sec. 74, adopted 12/3/19; Ordinance 7404 adopted 2/21/2023)
(A) 
Identification of Trees to Be Removed.
Trees that are proposed for removal must be flagged or otherwise identified in order to differentiate those trees from preserved trees prior to commencement of development or redevelopment activity.
(B) 
Protection Measures for Trees to Be Preserved.
The critical root zone of all preserved trees must be surrounded to create an area of non-encroachment by placement of appropriate protective fencing around the drip line of the tree during site preparation and construction. The original natural grade around the tree inside the drip line must not be disturbed in any way. The area within the protective fencing must not be used for parking vehicles or equipment, for materials storage, or for chemical wash-out areas.
(C) 
Protection Mandatory for Preserved Trees.
It is unlawful to do anything to, or near, a preserved tree that would likely, either immediately or over time, cause the tree to die, including severe pruning, trunk or bark damage, burning or intense heat, the introduction of toxic gaseous or liquid substance to the ground under the tree’s drip line or to the air around the tree or to the tree itself, or any other similar harmful act.
(Ordinance 6773 adopted 5/19/15)
(A) 
Credit for transplanted trees.
(1) 
Healthy protected trees less than six inches (6") in DBH qualify for one-inch (1") of replacement credit for each inch of the transplanted tree.
(2) 
Healthy protected trees between six inches (6") and up to 12 inches (12") in DBH qualify for two inch (2") replacement credit for each inch of the transplanted tree.
(3) 
Healthy protected trees between 12 inches (12") and up to 24 inches (24") in DBH qualify for three-inch (3") replacement credit for each inch of the transplanted tree.
(4) 
Health protected trees 24 inches (24") or more in diameter qualify for five-inch (5") replacement credit for each inch of the transplanted tree.
(B) 
Credit for preserved trees.
(1) 
A credit against mitigation shall be authorized for the preservation of any tree provided that all of the following apply:
(a) 
Said tree to be preserved is a minimum of six inches (6") DBH and is listed as a Class 2 tree.
(b) 
Said tree to be preserved is located in an exempted area or is otherwise free from mitigation requirements
(c) 
Said tree is protected from future removal, destruction or critical alteration by the establishment of protective covenants, easements, or agreements.
(d) 
Having met the following, the following credits would apply:
(i) 
6" to 11" equal a 1:1 mitigation.
(ii) 
12" to 17" equal a 2:1 mitigation.
(iii) 
18" and greater equal a 3:1 mitigation.
(2) 
Subsequent removal, damage, or critical alteration of any tree used for credit as identified above shall require mitigation replacement in accordance with this article.
(3) 
If any Protected and/or Replacement Tree(s) die within two (2) years of initial planting or issuance of Certificate of Occupancy and is brought to the attention of the Director or the Director's designee, the original permit application shall be subject to the same replacement fee as for the Protected Tree.
(C) 
Replacement trees.
Replacement trees for single-family, duplex, or townhouse residential development projects that will have a common area must be placed within the common area and may not count as the trees that are required on each residential lot per Section 4.37(A) and 4.37(B) in Article 3 of this Chapter 4.
(D) 
Credit for preserving existing tree-lines adjacent to residential districts.
A person, property owner, or developer, must comply with the following provisions related to existing tree lines adjacent to residential districts:
(1) 
A minimum fifteen-foot non-disturb zone is required along any side or rear perimeter of a development or redevelopment site, regardless of the type of development or redevelopment that is adjacent to a residential zoning district if any existing protected tree(s) exists within such area.
(2) 
Existing protected trees that are located within a non-disturb zone must be protected and preserved; they will be given additional credit at a rate of one hundred and fifty percent of their caliper size (for example, a preserved 9" caliper tree, which would normally get a credit for one large canopy tree per Table 4-8, will be considered to be a 13.5" caliper tree, which would receive credits for two large canopy trees).
(Ordinance 6773 adopted 5/19/15; Ordinance 7404 adopted 2/21/2023)