Forest cover dynamics in the Pacific Northwest west side: regional trends and predictions.

Abstract

The objectives of this paper were to (1) analyze recent rates of transitions among forest cover types on private timberland, (2) identify differences by ownership class, and (3) project future changes under different scenarios related to current policy issues in the Pacific Northwest. Timber harvests are the dominant class of disturbance on private timberland in western Oregon and Washington. Net changes in forest type areas depend on the relative mix of natural and human-related forces. Transitions among forest types after harvest may be planned, as in conversion of red alder (Alnus rubra Bong.) to the commercially preferred Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), or stochastic successional changes, such as reversion of disturbed areas to red alder in the absence of intervention. Projected areas of Douglas-fir and red alder were notably different under a scenario without harvests versus a scenario in which the rate of partial harvesting is increased. Areas of Douglas-fir were projected to increase under selected scenarios for both industrial and nonindustrial private ownerships. Conversely, areas of red alder are projected to decrease under selected scenarios and for both ownerships.

Citation

Alig, Ralph J.; Zheng, Daolan; Spies, Thomas A.; Butler, Brett J. 2000. Forest cover dynamics in the Pacific Northwest west side: regional trends and predictions. Res. Pap. PNW-RP-522. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 22 p