Summary
During the Spring of 1998, the senior class of Forest Engineering undergraduates of the University of Washington, under the direction of Dr. Peter Schiess, developed a harvest plan for 13,000 acres of state lands in the Northwest portion of the Washougal Landscape (T03N R05E and T03N R06E, WM) east of Vancouver, WA (A Management Plan for the Washougal Landscape, June 1998). The report you are reading today, is a condensed version of the harvest plan proposed to the Southwest Region Department of Natural Resources. This report focuses on the silvicultural alternatives of harvesting practices as dictated by the Habitat Conservation Plan (HCP) and economic drive for revenue.
According to the 1997 HCP, at least 50 percent dispersal habitat for the Northern Spotted Owl must be maintained in each watershed. A recent DNR habitat survey in our planning area near Washougal, WA concluded that just under 50 percent of the area currently meets dispersal habitat requirements as designated by the HCP. The habitat criteria are as follows on a per acre basis:
Due to the harsh growing conditions, we have found that the stands in this area have trouble meeting the minimum height requirements and the relative density constraint.
The main objectives in creating a harvest plan for this area, then, are to maximize economic return to the Trust, and to maintain at least 50 percent dispersal owl habitat. In our analysis, we looked at three different silvicultural options:
Using growth models, our analysis has shown that both thinning options in our planning area fail to create dispersal habitat conditions within the next 25 years. The stands are too mature to recover from thinning to create habitat in the areas of relative density and minimum height. We have also shown that 85 percent of the area will reach habitat conditions on its own within the next five years. Since thinning options do not show benefit in the creation of dispersal habitat, and are much more costly than the traditional method of regeneration harvests, they were not considered realistic in this area. Furthermore, we believe that it is reasonable to sustain a harvest of four million board feet a year from the area in regeneration harvests, and still maintain the HCP requirements for dispersal habitat. A Management Plan for the Washougal Landscape
outlines a recommended schedule of regeneration harvest units in order to maintain FPA and HCP requirements, and still sustain a 4 million boardfeet per year harvest volume. Since the initial stand data available at the time of the analysis was limited, we suggest revisiting our analysis when more stand data becomes available from the forest inventory (FRIS).