Linking crown fuel biomass to surface fuel accumulation for improved fuels and fire planning

Land managers rely on fuel load estimates and fire behavior models to make decisions about forest treatment planning and prioritization. While fuel estimates are fairly easy to obtain for open canopy forests, it is more difficult to accurately estimate and represent fuel loads in forests with dense canopies, complex landscape structures, and in ways that incorporate post-fire or post-harvest ecological processes and fuel accumulation. This project uses Wildfire Crisis Strategy priority landscapes where prescribed fire treatments are being used to test and demonstrate improved fuel mapping strategies in fire-adapted forests in the western U.S. 

Photo Credit

Wade Tinkham, USFS

Both forest crown and surface fuel loads need to be characterized to accurately estimate forest fuels and understand fire behavior. To more accurately characterize forest fuel loads, the research team will use remote sensing methods (Airborne laser scanning, also known as LiDAR) combined with Forest Inventory and Analysis data. First, to characterize the surface fuel loads, the project team has developed a novel, spatially explicit model that more accurately predicts surface fuel components such as litter accumulation and down woody debris. The projects team will then couple the surface fuel mapping with the remotely sensed canopy fuel estimates to improve fuel parameter inputs for use in cutting-edge, physics-based fire behavior models. 

The researchers will work with National Forest System partners in Forest Service Regions 3 and 4 to integrate their research findings into fuel models that can be used for mechanical fuels and prescribed fire treatment operational planning. The resulting maps and tools can be adopted by managers in forests throughout the western U.S. to help achieve forest health and fuels reduction goals. 

Objectives

The overall project objective is to increase the accuracy and resolution of surface fuel load and crown biomass fuel load estimates used in forest treatment decision-support tools, models, and maps. Specific objectives are as follows:

1. Map tree crowns from remotely sensed point clouds in Wildfire Crisis Strategy landscapes in Forest Service Regions 3 and 4. 
2. Estimate tree crown biomass using Forest Inventory and Analysis' National Scale Volume Biomass equations and input tree diameters. 
3. Estimate surface fuel accumulation, incorporating litter deposition, decomposition, and time since fire. 
4. Generate canopy and surface fuel density maps at high resolution for managers to use in mechanical fuels reduction treatment planning in selected Wildfire Crisis Strategy landscapes in the western U.S. 
5.  Generate 3D fuel density inputs to existing fire behavior models for managers to use for prescribed fire treatment planning in the same Wildfire Crisis Strategy landscapes.

6. Test and demonstrate the transferability and applicability of the process in other dry frequent-fire forests in the western U.S.

    

Expected Project Results

Expected Outputs:

• Demonstrated methods and improved capability to couple surface fuel accumulation to canopy fuel load in western U.S. forests using remote sensing data; methods and applications will be published as refereed publications and as a manager-focused Science You Can Use Bulletin.
• Publicly available maps and datasets from multiple Wildfire Crisis Strategy landscapes, which can be used to support management decisions and future analysis. 

• Manager-oriented workshop and webinars to share best practices for wider implementation. 

   

Expected Outcomes:

The project team will develop an improved approach to fuels mapping that can be used in forest and fuels treatment design and planning for Wildfire Crisis Strategy landscapes and western U.S. forest ecosystems. The project team will work to incorporate these improved tools into existing decision support and planning tools to increase their usability in on-the-ground operations. The improved map products are anticipated to result in more effective fuels treatment and prescribed fire planning, leading to more acres treated either mechanically or using prescribed fire. Ultimately, the project aims to develop tools that can be used by managers to help reduce the threat of catastrophic wildfire and increase forest resiliency and other ecological benefits in the fire-adapted landscapes throughout the western U.S.