23-103808-CalculatingTreeUnits92523` DEPARTMENT OF COMMUNITY DEVELOPMENT
CITY OF 33325 8`h Avenue South
Fe d e ra I Way Federal Way, WA 920
253-835-2607;Fax 253-835-2609
www.citvoffederalway.com
CALCULATING TREE UNITS
This form can be used to demonstrate how you will meet the minimum tree unit requirement for
your site and should accompany your submittal. Trees to be retained or planted must also be
shown on your submitted site plan, or a separate tree plan.
(lot size in square feet)
43,560 (sf/acre) = 0:')`2- x. (units/acre) _
(lot size in acres)
21
(minimum tree units)
Existing Trees
Includes all trees except invasive species and hazard trees
Tree Size (diameter at breast height /4.5')
# of Trees
to Remain
Tree Units
Total Units
1" to 6" dbh
x 1.0
-
> 6" to 12" dbh
x 1.5
> 12" to 18" dbh
x 2.0
> 18" to 24" dbh
x 2.5
- S
> 24" dbh
x 3.0
-
Total Existing Tree Units to Remain
Replacement/Additional Trees
Evergreen Trees - minimum 6' in height at planting
Deciduous Trees - minimum 2" caliper at planting
Large Canopy = 1.5 Tree Units Medium Canopy = 1 Tree Unit Small Canopy = .5 Tree Units
Tree Species
S anop/yl g)
nj/S
Units Tree
# of Trees
Total Units
Q► ��
a-� �,w.
C
_
Total Proposed Tree Units to be Added
CA
Total Existing and Proposed Tree Units
Bulletin #073 - June 8, 2016 Page 1 of 1 k:\Handouts\Calculating Tree Units