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Article 5: Development Standards
Section 5.4. Tree Protection
5.4.4. Tree Canopy Retention
Morrisville, NC
June 2013
Unified Development Ordinance - Public Hearing Draft
Page 5-7
Table
5.4.4.A:Existing Tree Canopy Retention Standards
Existing Tree Canopy
Cover
1
Minimum Percentage of Existing Tree Canopy Cover to be Retained
Single-Family Attached and
Multifamily Development
Nonresidential and Mixed Use Development
100%
19%
7%
80%
24%
9.5%
60%
29%
12%
40%
34%
14.5%
20%
39%
17%
0%
44%
19.5%
NOTES:
1. Existing tree canopy cover is the percentage of a development site (excluding proposed street rights-of-way, existing
utility easements, and natural water surface areas) that is covered by existing tree canopy before development or land
disturbing activity.
ILLUSTRATIVE EXAMPLE: The tree survey
establishes that 65% of a 100,000-square-
foot multifamily development site is covered
by existing tree canopy. Because 65%
represents 25% of the difference between
60% and 80%, the minimum required tree
canopy retention for the site is 25% of the
difference between the requirements for
60% tree cover (29%) and 80% tree cover
(24%), or 27.75% of the existing canopy
tree cover. This equates to 18.04 % of the
total development site. (65% x 27.75% =
18.04%), yielding a tree protection area of
approximately 18,038 square feet.
B.
Priority Retention Areas
296
Priority area for retention of existing tree canopy cover shall include the following, listed in priority
order:
1.
Existing tree canopy area containing specimen trees and their associated root zones;
2.
Existing tree canopy area located in riparian buffers, wetlands, or wetland protection areas;
3.
Existing tree canopy area containing stands of mature deciduous trees;
4.
Existing tree canopy area with natural grades of 15 percent or more;
5.
Existing tree canopy area containing trees and other vegetation needed for required perimeter
and streetyard buffers and landscaping; and
6.
Existing tree canopy that is a part of wildlife habitat and other sensitive natural areas.
296
This prioritizes existing tree canopy cover that should be retained.