contribution of roads to stream sedimentation, and had already begun experiments to measure the erosion rates of various logging practices. A two- decade experiment begun in 1952 in three adjacent watersheds in a rugged region of western Oregon documented that a clearcut area using "high- lead" cables instead of roads to lift the logs out averaged three times the erosion rate of the adjacent undisturbed watershed, while the roaded and logged area averaged 109 times more soil loss than the undisturbed forest.39 But studies of this type did nothing to slow the logging.
Besides the problem of soil loss and stream sedimentation, logging affected soil productivity and forest regeneration capabilities in other ways. Exposure to the drying effects of sun and wind reduced soil moisture, often making it more difficult for seedlings to get established, especially in arid regions. Even worse, compaction from logging machinery, especially on skid roads, radically reduced soil porosity and permeability, leaving remaining topsoil in a less productive and more unstable condition. Roads caused by far the worst episodes of erosion, compaction, and productivity losses. A study by a Weyerhaeuser soil scientist and a University of Washington professor published in 1955 measured the precise changes in macroscopic soil pore space and soil permeability on logged areas of Weyerhaeuser's tree farm, and contrasted tree seedling survival and vigor on skid roads with adjacent cutover areas off the skid roads. They found that permeability was reduced 35 percent on the cutover areas and 92 percent on the skid roads, while soil pore space showed a loss of 11 percent on the cut areas and 53 percent on the skid roads. Importantly, skid roads comprised one-fourth of the total logged area on average. These studies further showed that 78 percent of seedlings survived on the unroaded clearcuts, while only half the seedlings planted in the skid roads survived. Of those that survived, 41 percent of the seedlings on the skid roads were rated "poor quality," while only 12 percent on the unroaded clearcut were rated poor.40
Willis Evans argued in his presentation to the SAF in 1959 that managing for high yield production under the profit motive did not protect the public interest in forests -- unless profit and wood production were defined as the sole public interest. On both private and public lands, he warned, "Too often the immediate economics of a situation rather than sound long-range con
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Publication information: Book title: A Conspiracy of Optimism:Management of the National Forests since World War Two. Contributors: Paul W. Hirt - Author. Publisher: University of Nebraska Press. Place of publication: Lincoln, NE. Publication year: 1994. Page number: 149.
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