Bonanza Creek LTER: Annual Active Layer Depths from 1972 to Present in the Wickersham Fireline Sites near Fairbanks, Alaska

In June of 1971 the Wickersham fire burned 6313 ha and provided an opportunity to study various fire effects. When wildfire burns through a northern black spruce forest there is usually a subsequent increase in depth of thaw, due to the reduction in the depth of the organic layer. The construction of firelines with heavy machinery involves the complete removal of the organic layer and results in an even greater increase in active layer. This study was designed as a long-term comparison between depth of thaw on firelines, burned and unburned open black spruce forest underlain by ice rich permafrost.