Landscape restoration of forest landscape structure based on historic disturbance regimes: A western Oregon case

Dispersed patch clearcutting of Douglas-fir/western hemlock forests on federal lands of the western Cascade Range in the 1950s-1980s created an unnatural landscape structure and diminished the extent of native forest.  In the early 1990s the patch clearcutting practice was ruled illegal in the range of the ESA-listed northern spotted owl, which occupies portions of northwest California and western Oregon and Washington.  In response to the benefits of fresh perspectives on forest landscape management, an exploratory landscape management plan was developed for a 17,500-ha area within the Willamette National Forest, based on historic wildfire disturbance regimes.  The resulting Blue River Landscape Plan seeks to restore forest stand and landscape structures to be more characteristic of historic conditions.  Dendrochronology-based interpretation of wildfire history and simulation modeling indicate that historic landscape structure, in terms of relative extent of forest age classes, was not seriously disrupted by the partially offsetting effects of the clearcutting and wildfire suppression, which occurred over a more extended period of time than the cutting.  However, clearcutting fragmented the forest in a fashion that had no natural corollary.  The Blue River plan employs partial cutting, long rotations, and a pattern of cutting that shift the overall landscape pattern toward a more historic condition.  Stand-scale treatments include a legacy dead wood, both standing and down, that historically was present, especially following severe disturbances.   The greatest challenge to implementing this type of plan is the social values associated with native forests of any size or condition in this area.