BMP - Tree Inventories - 21

*	 The use of calipers is sometimes specified for measurement on smaller
trees, following the American Standard for Nursery Stock: at 6 in (15
cm) above the ground line if dbh is less than 4 in (10 cm) or at 12 in
(30 cm) from the ground if dbh is greater than 4 in (10 cm).

Condition

There is no single system used to rate tree condition. Some inventories use
a system set up by the Council of Tree and Landscape Appraisers, although
that system was designed for individual tree appraisal rather than forest
management.
Two examples for rating tree condition can serve as a guide for the manager considering an inventory. The simplest system applies a number to a
qualitative scheme, for example:
Code 1: good (with or without a higher category of " excellent " )
Code 2: fair
Code 3: poor (with or without a lower category such as " critical " )
Code 4: dead
The definitions in such a simple system must be as precise as possible (for
example, fair = at least one major tree health defect) and applied consistently
across the entire inventory process. Many variations of this scheme exist.
A somewhat more analytical approach tries to separate tree structural
condition from tree health.
Tree Structural Condition
Code 1 = extreme problems 	
Code 2 = major problems 	
Code 3 = minor problems 	
Code 4 = no apparent problems 	

= unstable
= poor, potential instabilities
= fair, no instability
= good

Health/Foliage Condition
Code 1 = extreme problems 	
Code 2 = major problems 	
Code 3 = minor problems 	
Code 4 = no apparent problems 	

= dead/dying
= poor
= fair
= good

Once again, it is critical that the terms (in this case, " extreme, " " major, "
" minor, " and " problems " ) be clearly defined and consistently applied for the
scale to provide useful information. The total can be equated to a condition
class ( " good, " " fair, " etc.) for easier understanding by nonprofessionals.

21
BMP - Tree Inventories

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