Ash Basal Area Reduction Model

2" Diameter Class

Version 2.0, Tara L. Eberhart, Andrew J. Storer, Linda M. Nagel

Copyright Michigan Technological University

Version 2.0 Input Requirements

4/2/2007

ASH Trees Only

Trees per Acre

This information should be available from stand and stock tables.

2" Size Class Increments

DBH Class "

No. Trees/Acre

% Phloem Basal Area

2

Retaining Small Trees

4

Target Percentages

6

Diameter Limit Cut

8

99%

10

95%

12

90%

14

75%

16

18

20

Retaining Large Trees

22

Target Percentages

Total

Diameter Limit Cut

99%

95%

90%

75%

Summary

This version of the model serves to show what diameter limit cut would be needed in order to reduce the total of ash phloem basal area in a stand.

Over 500 ash trees were measured to find the average phloem width and calculated phloem basal area by diameter class.

Phloem is the food source and breeding substrate used by emerald ash borer in ash trees.

This model only works with the ash component of a stand regardless of total stand size, other tree species presence, or how much ash there is present.

Depending on management goals, this model can be used to determine a lower diameter limit cut to retain small trees,

and an upper diameter limit cut to retain large trees.

Use of this model in management decisions will reduce the ash resource available to emerald ash borer

by a target percentage and help maintain ash as a component in our forests.

Note: basal area reduction will reduce the amount of phloem in the stand by a target level,

thereby reducing the population potential of eab, not ensuring remaining ash to be uninfested.