Post-harvest regeneration of montane Abies amabilis forests in northern Washington, USA

摘要

The effects of regeneration treatments on current stand composition were analyzed in a high-elevation forest approximately 20 years after harvest in the Cascade Range, Mt. Baker-Snoqualmie National Forest, Washington (USA). Post-harvest treatments included sites that were (1) broadcast burned and planted with Abies amabilis, (2) unburned and seeded with A. amabilis and A. procera, and (3) unburned and planted with A. amabilis. All sites are currently dominated by A. amabilis and Tsuga heterophylla. Burned-planted sites have a smaller proportion of A. amabilis than unburned sites, and burned sites have less advance regeneration of all species than unburned sites. Although future stand composition is difficult to predict, comparison with historical stand data for this location indicates that regeneration treatments, including seeding and planting, have not had significant effects on overstory species dominance. If rapid regeneration of A. amabilis is a management objective, then post-harvest burning should be avoided to encourage advance regeneration of this species.