Contribution to Book
WD Shepperd, D Binkley, DL Bartos, TJ Stohlgren, and LG Eskew compilers
Sustaining Aspen in Western Landscapes: Symposium Proceedings
USDA Forest Service Rocky Mountain Research Station
A 3-year study of evapotranspiration from aspen clearcuts 1 to 14 years of age indicated the following: (1) The annual evapotranspiration from 1- to 5-year-old clearcuts ranges from 0 to 143 mm less than a mature forest on the same site. Evapotranspiration is highly dependent upon the amount of precipitation. (2) These effects can vanish in as few as 2 years with low precipitation (300 mm) or persist for 40 to 45 years with high precipitation (600 mm). These results were confirmed by data from the Spring Creek experimental watershed. Simulated water yield increase from the harvested catchment averaged 16 mm, compared with 16.3 mm estimated from the paired watershed data. In planning harvesting scenarios on flood-prone watersheds, full hydrologic recovery should be assumed to occur 45 years after harvest. Harvesting sequences designed using this approach should not cause a measurable increase in flooding levels or flood frequency.
Swanson, RH and Rothwell, RL. 2001. Hydrologic recovery of aspen clearcuts in northwestern Alberta. WD Shepperd et al (compilers). Sustaining Aspen in Western Landscapes: Symposium Proceedings. Proceedings RMRS-P-18. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. Fort Collins, CO.