Deer mouse movement in forest habitat

Early, economical stocking of deforested areas is a major problem of foresters in theDouglas-fir (Pseudotsuga menziesii) belt. Many factors adversely affect regenerationefforts, such as animals, disease, weather, and others. Of the animals, deer mice(Peromyscus maniculatus) have received much attention because of their abundanceand consumption of tree seed. The deer mouse movement in forest habitat is ofimportance in direct seeding operations in the Douglas-fir belt. It is recognizedthat Peromyscus soon occupy underpopulated habitat (Hooven 1963; Spencer 1955;Gashwiler 1959). Although much of this colonization is probably the result ofmovement from surrounding areas (Blair 1940; Stickel 1946; Hooven 1953; Gash-wiler 1969b), specific data on the movement of animals in forest habitat are scantilydocumented. It was with the hope of adding to the understanding of this movement,and thus aiding foresters, that these data were compiled.
The investigation was made from October 1955 until October 1958 inclusive,on the H. J. Andrews Experimental Forest in Lane and Linn counties, Oregon, nearthe town of Blue River. The forest is located within the boundaries of the WillametteNational Forest on the west slope of the Cascades. It includes the entire watershedof Lookout Creek, a tributary of Blue River.
A 48-acre clearcut (5B) and adjacent forest were selected for study. This areahas an elevation ranging from about 2900 to 3500 ft and a southerly slope of about18 percent. The terrain is bench-like alternating with steep slopes, and the soil isporous clay loam of volcanic origin (Berntsen and Rothacher, 1959). Interpolatingthe Berntsen-Rothacher precipitation data on the basis of elevation gives a roughestimate of about 113 inches of moisture per year.
The old-growth timber on the study area was mostly overmature and was startingto deteriorate. Percentages of sound timber logged on the clearcut were: Douglas-fir87 percent, western hemlock (Tsuga heterophylla) and others 12 percent, and westernredcedar (Thuja plicata) 1 percent. The clearcut was burned in October 1955. Itwas covered with ashes and charred wood when this investigation was started thelatter part of the month. By the end of the study, three years after burning, totalground coverage was estimated to be about 14 percent woody plants (includingconiferous reproduction) and 16 percent herbaceous species.