Fine woody fuel particle diameters for improved planar intersect fuel loading estimates in Southern Rocky Mountain ponderosa pine forests

Abstract

Fuel loading estimates from planar intersect sampling protocols for fine dead down woody surface fuels require an approximation of the mean squared diameter (d2) of 1-h (0–0.63 cm), 10-h (0.63–2.54 cm), and 100-h (2.54–7.62 cm) timelag size classes. The objective of this study is to determine d2 in ponderosa pine (Pinus ponderosa) forests of New Mexico and Colorado, USA in natural, partially harvested, and partially harvested and burned sites to improve fine woody fuel loading estimates. Resulting estimates were generally higher in the 1- and 10-h classes and lower in the 100-h classes when compared with previously published values from other regions. The partially harvested and burned values for 1- and 100-h classes were also significantly lower than in the other stand conditions. Using bootstrap analysis, it was determined that 35 samples would be sufficient to create an accurate estimate of d2 values.