Height of Crown Scorch in Forest Fires

Abstract

A relation between fire behavior and crown scorch height is derived from measurements on 13 experimental outdoor fires. The range of data includes fire intensities from 16 to 300 kcal/s-m, and scorch heights from 2 to 17 m. The results agree with established theory that scorch height varies with the 2/3 power of line-fire intensity. The effects of air temperature and wind speed on scorch height are treated as well. The derived relations could be useful to those interested in prescribed burning under a crown canopy, ecological response of trees to fires of varying intensity, and timber losses following forest fires.