Landscape Editing Tips

Important! Default Fuels Treatment / Disturbance Edit Rules are ONLY available for LANDFIRE 2012 and 2014 landscapes within the contiguous United States. Versions for more recent landscapes are under development.

User Created Edit Rules can be applied to any landscape.

User Created Rules

When creating editing rules, note that:

  • Landscape features are not dependent upon each other when editing. When editing an LCP with User Created Edit Rules, changing one feature such as Fire Behavior Fuel Model, will not make changes to other features such as canopy height cover, etc. For example, changing a Timber Understory Fuel Model to a Grass Fuel Model will change the Fuel Model, but all the timber canopy features will remain until you edit them as well.

  • When decreasing canopy cover, which is in units of 'percent', IFTDSS uses percentage points. For example, decreasing 55% cover by 50 will result in 5% cover. An efficient way decrease the canopy cover by half, would be to multiply the canopy cover by 0.5.

Time Saving Tips

  • Applying an edit to an entire landscape: Using a selector that covers your entire landscape, such as "elevation is greater than or equal to 0" can be a quick way to select your entire landscape for a given edit if needed. This can be especially useful as there is no 'select all' feature in the IFTDSS Edit rules.

  • Applying an edit based on aspect: Use the aspect selector if needed to update fuel models on north or south facing slopes. For example, selecting an aspect less than or equal to 202 degrees and setting the fuel model to 165, and selecting an aspect greater than or equal to 158 degrees and setting the fuel model to 165, will set the the fuel model to 165 for all aspects from 158 to 202 degrees. Aspect must be addressed in two separate rules, as in the screen capture below, in order for this rule to function.

    aspect between 158 and 202 selected in order to change the fuel model to TU5 on those aspects.

Why replicating with User Created Rules can be a challenge

Because Default Edit Rules are not available for every version of LANDFIRE data, you may be interested in recreating Default rules via the User Created edit rules. It is difficult to apply the User Created Edit Rules to same effect as the Default Edit Rules because the Default rules are based on other settings and characteristics in the LANDFIRE data that are more complex than what the User Created Edit Rules offer. However, we've included some information from the IFTDSS Team that may useful in these efforts.

The IFTDSS Default Edit Rules are driven by LANDFIRE Look-up Rules, based on LANDFIRE veg type, cover, height, and the lcp features. While the description in IFTDSS generally summarizes what the rule does, there’s bound to be some variation or other details based on modeled tree growth after the disturbance.

Ways to approximate default rules

To capture as many factors as possible it may be worth consulting your silviculturist and have them do paired FVS runs for a like stand. Then use change factors like increasing the Canopy Base Height by x%. Then those outputs could be referred to as you develop your User Created Edit Rules, making rule sets based on the changes due to treatment. For example, thinning trees up to 3” diameter at breast height (DBH) in FVS (Forest Vegetation Simulator) may reduce canopy cover by 5% but only in areas where it’s >60% to start. Translating that to a User Created Edit Rule, you could make a rule that multiplies Canopy Cover by 0.95 where it is >60%.

It may also be worth noting that removing small trees might not have a big change on any canopy characteristics, depending on the current conditions. Since the Canopy Cover, Canopy Base Height, Canopy Height and Canopy Bulk Density is heavily weighted to the larger trees, though that depends on the vegetation/stand.

If you don’t have FVS experience, or access to someone who does, an alternative would be one of trial and error within IFTDSS. In that case you could change specific stand characteristics with the User Created Edit rules, run behavior on the subsequent landscapes, calibrate your landscape edits based on that. Another option would be focusing on the Fire Behavior Fuel Models, making changing their, and analyzing the fire behavior that results. This last step is important in any case to ensure the fire behavior being modeled looks accurate given the weather and fuel moistures you’re working with.

Cross walking something like DBH to fuel models is tricky and you may end up needing to use a shrub model if you are trying to model fire behavior in thicker stands with a lot of understory.

Other Landscape Editing Resources