Developing Treatment Alternatives - Colville National Forest Example
Section 6 – Comparing and Adding Treatment Alternatives
Comparing the Alternatives
After clicking Compare on Map, the map appears in splitscreen mode. This allows you to view information from each tab on the right side of the screen, while allowing you to view “My Map” on the left. You can open or close this feature anytime by selecting the opposing arrows icon at the top of the screen.
Initially, you’ll see a simple landscape change map, indicating which pixels experienced a Fuel Model change post-treatment.
To view the change in Flame Length after the treatment, open Layer List and check the box next to: “Landscape Fire Behavior Change: Watershed 20 Thn Pburn 10 yr/North Selkirk CFLRP LF2014 Un”. This layer shows the difference between post-treatment and pre-treatment Flame Lengths. With a glance, you can see that all the dark blue showing on those South/North Facing slopes that had initially shown very high flame lengths, are now indicating significantly decreased flame lengths and fire intensity.
Tip: The change map is generated on the fly. To access the map later you can select the landscape in the Develop Treatment Alternatives task, and click through each tab to get back to this point.
To access the summary reports, you can either find them in your project folder in My Workspace, or click the Compare in Summary Report button again and click on the links displayed in the pop-up box.
In this case, go to My Workspace and first select, “Watershed 20 Thn Pburn 10 yr/North Selkirk CFLRP LF2014 Un - compare LCP/Watershed Proposed Treatment Areas”, you may have to hover over the shortened name to display the full name. Once this is selected, click View Summary.
In the first bar graph, note the acreage for the AOI is displayed. This is a quick way to confirm the Develop Treatment Alternative task and resulting reports were actually run to quantify only the AOI, not the entire landscape.
Review the pre– and post– treatment results for each landscape characteristic. These reports have the same quantitative components as the reports you viewed earlier, but they compare the change in acreages in the specified treatment area, or mask, before and after the selected treatment was applied.
Tip: Note the values in your report may vary slightly from the ones we're about display. This is because the area of interest you drew at the beginning at this tutorial won't exactly match the one we drew here.
In the Fuel Model bar graph, you can see that the green corresponds to pretreatment fuel models in the treatment area, while blue corresponds to post-treatment. It appears that most of the TU5 acres were changed to GS2 post-treatment. Looking at the tabular data below, you can see that in fact, 54 % of the treatment area is now Fuel Model GS2 following this treatment, which (according to the fuel model) will re-sult in a decrease in spread rate and flame length.
The Fuel Model Percent Difference graph and pie charts tell the same story.
Next, go to My Workspace and navigate to the Fire Behavior (Model) Compare Report, “Watershed 20 Thn Pburn 10 yr/North Selkirk CFLRP LF2014 Un - compare model/ Watershed Proposed Treatment Areas”, and click View Report.
As in the landscape Compare Report, green correlates with pre-treatment, while blue indicates post-treatment results in the bar chart. You can see from this bar chart that the number of acres in the lower Flame Length bins goes up post-treatment, while the number in the higher Flame Length bins goes down, indicating a decrease in higher Flame Length post-treatment. The table to the right quantitatively supports this, clearly showing the acres shifting toward the lower flame length bins, post-treatment.
The Percent Difference Graph for Flame Lengths demonstrates the shift towards lower Flame Lengths post-treatment. You can see the positive percent difference in the 0-1, 1-4, and 4-8 foot bins, while the bins correlating to higher Flame Lengths indicate a drop in the percent difference. The pie charts tell the same story, plainly showing the smaller sections of red/orange/yellow in the post-treatment chart.
Scroll through the rest of the summary report to view the rest of fire behavior characteristics.
Adding an Additional Treatment to Treatment Alternatives
Now you’ll look at the effects of applying a subsequent broadcast burn after the light thinning/pile burning. One of the initial objectives is to re-introduce low intensity fire in this area and it’s an important step in treating this landscape. Additionally, you can see how this follow-up treatment will affect modeled fire behavior:
- Navigate to the Develop Treatment Alternatives workflow again and select the same Originating Land-scape and AOI.
Navigate to the Edit Landscape tab.
- This time, choose the landscape with your earlier edits as the Starting Landscape: “Watershed 20 Thn Pburn 10 yr”
- Select the Wildfire Default Rule.
- Specify Low severity fire. As before, you can hover over this text or consult Landscape Editing—Default Fuel Treatment and Disturbance for the detailed explanation of the rule.
- Select a treatment time of 1 year
- Apply this rule to your “Watershed Proposed Treatment Areas” mask.
Click Add to Rules.
After the rule is added, give the landscape a detailed name (Watershed 20 Thn 10 yr Rx 1 yr) and click Save New Landscape.
Skip the Model Input tab this time. That input was saved from your last run, and the weather parameters must be kept constant in order to compare the results of the landscape changes.
Go to the Run Model tab and click Run Model. You may need to click the Refresh button next to Landscape if your edited landscape is still being built.
Next, move to the Compare Alternatives tab.
Compare the original landscape with this new one by selecting:
- “Watershed 20 Thn 10 yr Rx 1 yr” as landscape “1”.
- Select “North Selkirk CFLRP LF2014 Un” as landscape “2”.
- Click Compare in Summary Report and initiate those reports.
- Click Compare on map to get a map view of your changes.