Fuel Treatments & Effects
Naturally-ignited Fire-use treatments
The effects of wildfire and logging on erosion from two small catchments of the Pine Creek drainage in Idaho, USA, were investigated. One catchment was clearfelled in 1972 and a wildfire burned in the study areas in 1973. The fire was more intense on the clear felled area (estimated fuels were 90 and 10 tons/acre on felled and unfelled areas, respectively). Considerable accelerated erosion (including both sill erosion caused by overland flow and splash erosion) occurred on the clearfelled area; the erosion was entirely postfire. Although the fire killed the trees on the unfelled area, the needles were not consumed. These began falling shortly after the fire and the resulting litter increased ground cover on the area. There was a tendency for greater water repellency of the soil on the felled area and for greater erosion on areas with thicker water repellent layers. The study reaffirmed the need for effective slash disposal techniques to minimize erosion problems on clearcut areas subject to wildfire.