Relationship of fire behavior to tallgrass prairie herbage production.

Abstract

Little evidence has been found to relate fire intensity to herbaceous vegetation response. Our objective was to determine if components of post-fire herbaceous standing crop in a tallgrass prairie could be related to either fire behavior variables or to time-temperature relationships. We used canonical correlation to relate standard fire behavior variables (fireline intensity, rate of spread, and heat per unit area) and time-temperature relationships (degree seconds at 3 vertical strata) to post-fire components of the herbaceous standing crop of tallgrass prairie. Spring headfires and backfires were applied to 10 X 20-m plots on a moderately grazed, shallow prairie range site in good to excellent range condition. The first canonical correlation of the 3 fire behavior variables and the standing crop variables generally indicated a strong relationship between the 2 sets of variates. The canonical correlation between the degree seconds and standing crop sets of variates was slightly less than the canonical correlation between the fire behavior parameters and standing crop. Neither the fire behavior canonical variate nor the degree second canonical variate was strongly related to any single component of the June or August standing crop, but this study demonstrates that fire behavior is a factor affecting community herbaceous vegetation response to fire in tallgrass prairie.