Ministry of Forests and Range Forest Inventory Audit Program (1992-1999)

How accurate is the current inventory?

To answer this important question, the Forest Analysis and Inventory Branch has developed an inventory audit methodology specifically designed to test the overall accuracy of estimates of the total standing volume in each timber supply area.

This inventory audit methodology entails sampling three primary components of the inventory:

1. The first component is the mature forested areas (forest stands greater than 60 years of age)--the audit tests the accuracy of the mature timber volume.
   
   
2. The second component tested is immature stands (less than 60 years of age but greater than the silvicultural classification of free growing)--the audit tests the accuracy of the site growth potential (site index) assignment for these stands.
   
   
3. The third audit test is of the photo-classification accuracy of the non-forest classification component of the inventory (areas such as lakes, gravel pits and alpine meadows).

The objective of the inventory audits program is to help identify TFLs or TSAs where the forest inventory needs attention.

Enough samples are taken to ensure statistically reliable results for the management unit as a whole. The amount of data collected, however, is not sufficient to make statistically reliable conclusions about specific areas or tree species.

The audits provide information that may be useful to the chief forester during determinations of the allowable annual cut-- offering a general assessment of the uncertainty associated with mature timber volumes, immature site index, and the non-forest classification. However, the audit results cannot justifiably be used to make specific adjustments to growth and yield and other information used in timber supply analysis and allowable annual cut determinations.

Reports on inventory audits for the following areas are now available here.