Hydrologic consequences of logging second-growth redwood watersheds

Abstract

Abstract - Streamflow, suspended sediment, and bedload have been gauged continuously since 1962 in the 473-ha North Fork and the 424-ha South Fork of Caspar Creek on the Jackson Demonstration State Forest. From 1963 to 1967, both 90-year-old second-growth watersheds were measured in an ""untreated"" condition. In 1967, logging roads were built in the South Fork. From 1971 through 1973, about 65% of the stand volume was selectively cut from the South Fork watershed. Logging began in the North Fork in 1985 and ended in 1991. The timber volume removed from the North Fork watershed approximated that cut from the South Fork in the early 1970's, but clearcutting rather than selective harvest was used. The size of clearcut blocks in the North Fork ranged from 9 to 60 ha and occupied 35% to 100% of individual tributaries. Logging-induced changes in peakflow were greatest for the first storms following lengthy dry periods. There was no significant change in large peakflows after logging. Annual runoff increased about 25% for a few years after logging, but returned to pre-logging levels within 15 years

Citation

Ziemer, Robert R.; Lewis, Jack; Keppeler, Elizabeth T. 1996. Hydrologic consequences of logging second-growth redwood watersheds. In: LeBlanc, John, ed., Conference on Coast Redwood Forest Ecology and Management, 18-20 June 1996, Humboldt State University, Arcata, California; 131-133