INVESTIGATING THE RELATIONSHIP BETWEEN BOLE SCORCH HEIGHT AND FIRE INTENSITY VARIABLES IN THE RIDGE AND VALLEY PHYSIOGRAPHIC PROVINCE, WEST VIRGINIA

Prescribed fires are carried out on the George Washington National Forest (GWNF) in West Virginia to promote long-term resource and social values, including tree regeneration, improving wildlife habitat and aesthetics, and maintenance of low woody fuel loading. Prescribed fire programs have increased on the GWNF over the past 20 years. Although prescribed fire is widely used on the GWNF, methods and techniques for monitoring fire behavior are still in the early stages of development. As part of a larger study to assess the effects of prescribed fire on invasive species in eastern West Virginia, we used simple linear correlation and regression analysis to investigate the relationships between plot-level 3-year post-fire bole scorch height parameters, fire temperature as estimated by thermocouple probes, litter consumption, and sapling mortality to better understand and predict fire effects in mixed-oak and oak-pine forests. We collected information on these parameters as they were observed on 36 research plots in an area where a prescribed fire had been applied in the Ridge and Valley physiographic province of eastern West Virginia. The prescribed burn totaled 313.6 ha and was conducted in March 2004. Neither overstory nor sapling bole scorch height variables were significantly related to thermocouple temperature measurements recorded at five locations on a southwest-facing slope ( a = 0.05). The sum of the sapling scorch heights was significantly related to litter consumption, but accounted for only 11 percent of the variation. However, all bole scorch height variables were significantly related to sapling mortality one growing season after the fire. This result further illustrates the usefulness of scorch height as an estimator of relative fire intensity, and provides a useful prediction model for xeric mixed-oak and oak-pine fire managers.