Long term responses of streamflow following clearcutting and regrowth.

Long-term changes in streamflow following forest cutting for three experimental basins show that streamflow declines with the logarithm of time as the forest regrows. The decline is related to vegetation regrowth, but is not a consistent function of simple stand measurements. The mixed hardwood forest of one basin was clearcut twice in 40 years. During the second regrowth period, streamflow increases were about one-half those after the first treatment. Concurrently, two other basins were cut whose mid-elevations are 400 m higher. Both streamflow increases were less than on the lower basin. Similar variability of increases for the three concurrent treatments appears partly related to precipitation.