DecAID Implementation: Post-Disturbance Salvage Sales

Quick Assessment for Salvage Sales Example

Objective

This example steps through a hypothetical potential salvage situation. It is an example of how disturbances in your Analysis Area, that aren't part of the updates included in the Region-wide Distribution Analysis, can be incorporated into your Quick Assessment. It is assumed that you have completed all the steps in the Quick Assessment up to Step 2 and have the Region-wide Distribution Analysis clipped and summarized to your Analysis Area.

Remember, the GNN data used in the Regional-wide Distribution Analysis is from 2012. The data have been updated for large fires (>1,000 acres) through 2014 using RAVG maps (http://www.fs.fed.us/postfirevegcondition/index.shtml). This example is one way to account for other disturbances have occurred in the analysis area since 2012, and to adjust the current conditions on the distribution histograms.

This analysis can be completed in GIS. However, for the quick assessment, a cursory look similar to this example will suffice.

Example

In the example analysis area there are the following disturbances that have not been incorporated into the Region-wide Distribution Analysis:

• Current fire
• Mountain pine beetle activity since 2012
• Past fires not included on RAVG maps

Assumptions will need to be made as to how many acres of each disturbance contribute to the snag density classes from the Region-wide Distribution Analysis. The adjustments below are just an example, use local knowledge and your best judgement to decide which snag density classes should be updated. Updates are tracked in Table 1 below. A spreadsheet is also available to assist with calculations if desired - Quick Assessment Worksheet. The acres in the example are entered in the first tab of the spreadsheet as an example of how the spreadsheet works.

Current fire - use information from BAER maps and add or subtract acres from each snag density class based on severity:

• High severity - 6,000 acres - add equally to last 2 snag density classes; subtract from the lowest snag density classes proportionally
• Moderate severity - 8,000 acres - add equally to middle 2 snag density classes; subtract from the lowest snag density classes proportionally

Mountain pine beetle - use information from the Regional Forest Insect and Disease Maps

• 500 acres with 24 to 36 dead trees per acre; add to that snag density class; subtract from the lowest snag density classes proportionally

Past fires not included in regional update -

• 240 acres salvaged - do not adjust acres for salvaged disturbances
• 500 acres not salvaged; 120 acres high severity and 200 acres moderate severity; add and subtract acres in the same manner as the current fire