Comparison of three methods for quantifying coarse surface fuel loading

Abstract

We compared three commonly used sampling methods for estimating coarse woody surface fuel (>7.62 cm diameter) loading: fixed-area plot, planar intersect using one transect, and planar intersect using two transects. Sampling occurred in ponderosa pine/ Douglas-fir (Pinus ponderosa/Pseudotsuga menziesii) dominated stands in the northern Rocky Mountains, USA. These methods commonly have tradeoffs in execution and accuracy that managers must consider. We found fixed-area plot sampling was more likely to capture log occurrence; planar intersect methods estimated zero loading on 23 to 47 percent of plots, but fixed-area sampling always captured some loading. Adding a second transect did not improve accuracy of sampling estimates at either high or low log loading when compared to fixed-area log loading. The three sampling techniques produced similar results at the unit level, but on an individual plot, the planar intersect method tends to overpredict log loading when actual loading is very low (< 1.0 kg m-2) and underpredict values as loadings increased beyond that level. These results suggest that planar intersect sampling can accurately be used to estimate log loading if numerous transects are installed. If sampling is constrained to one transect per stand, then fixed-area plot sampling is recommended.

Parent Publication

• Proceedings of the Fire Continuum-Preparing for the future of wildland fire; 2018 May 21-24; Missoula, MT

Citation

Bowen, Katelynn J.; Keyes, Christopher R.; Hood, Sharon M.; Seielstad, Carl; Lutes, Duncan. 2020. Comparison of three methods for quantifying coarse surface fuel loading. In: Hood, Sharon M.; Drury, Stacy; Steelman, Toddi; Steffens, Ron, [eds.]. Proceedings of the Fire Continuum-Preparing for the future of wildland fire; 2018 May 21-24; Missoula, MT. Proceedings RMRS-P-78. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. p. 22-30.