Ash Phloem
Reduction Model Examples

Version 2.0

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

**Examples of Data Entry**

The
example in Figure 1 shows real stand data that has been entered, with the % Phloem
Basal Area that the Trees per

Figure 1 – Input Page with Example
data filled in

* % Surface
Area Column* - The column to the
right of the green Trees per

* Relationship
Cumulative Phloem Basal Area and DBH charts & Target % tables* – Notice there is one output chart given with
cumulative phloem basal area, with the slope descending to show the
relationship and find the diameter limit to retain small trees. The chart
corresponds with most common type of diameter limit harvesting of retaining
small trees, which is removing all trees above a specified diameter at breast
height. This chart matches up with the
first table on the top left

The second table of diameter limits uses same data as
the first one, but is showing what the diameter limit harvest would be to
remove smaller trees and retain large diameter trees. The user will see that the diameter limits
shown in the top table on the right to retain large trees are much larger than
in the table to retain small trees.

With this type of harvesting, the forest manager can still
remove a target amount of phloem available to emerald ash borer but retain
seedlings (trees to small to be cut at all) and the larger diameter trees. The diameter limit given for this type of
harvesting indicates the size at which trees are left rather than cut, so all
trees less than the specific diameter are removed. Using this example, to retain large trees and
still remove 95 % of the ash surface area, all trees less than 20.9 inches
should be removed.

The
same data entry applies to the 1” diameter class model. In Figure 2, the 1”
inch diameter classes have been filled in using Trees per

Metric
data can be entered and applied the same way by choosing the metric versions of
the model to enter data, depending on the type of data the forester has
available, either 2 cm or 1 cm size classes of ash trees per acre.

Figure 2 – Example using 1 inch
class