Post-treatment monitoring shows the success of fuels-reduction treatment in an Arizona forest

Wilburforce Fellow Miranda Gray makes a case for monitoring as a valuable tool for assessing the efficacy of forest treatments.

CSP’s Miranda Gray recently conducted an analysis to monitor the effects of forest treatments in the Upper Beaver Creek (UBC) watershed of northern Arizona, where a prescribed fire was implemented in 2015. The goal of this treatment was to reduce dense fuel accumulations and encourage the growth of grasses, shrubs, and wildflowers. Supported by the National Forest Foundation through the Northern Arizona Forest Fund, this study entailed analyzing high-resolution imagery to identify evidence of a restored landscape and provide a quantitative information about outcomes. Although monitoring is essential for understanding the results of forest treatments, it is often overlooked during project planning and budgeting. Remote-sensing approaches can be ideal for tracking conditions before and after prescribed fires.

Gray found that canopy cover — a key indicator of potential fire behavior — was reduced by 15% after the treatments. The results were applied to a fire model, which also identified a corresponding trend: a 27% reduction in potential fire intensity and a 10% reduction in the potential for active crown fire. In areas with the lowest initial canopy cover, the imagery showed that grasses and forbs likely benefited from a post-fire nutrient flush and reduced competition from large trees. Both of these outcomes — an increase in herbaceous fine fuels and a decrease in canopy cover — are expected to increase the potential for surface fires, an important characteristic of healthy forest dynamics.

To read Miranda’s recap of this work, visit her guest blog post on NFF’s web site.