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Abstract
Engelmann spruce seed production and dispersal, and seedling establishment in the central Rocky Mountains indicate that in the Abies Iasiocarpa/Vaccinium scoparium habitat type, shaded, mechanically scarified, mineral soil seedbeds on north aspects can be adequately restocked naturally within a 5-year period in clearcut openings 300 to 450 feet wide. With shade or scarification alone, size of opening that will restock is reduced to 200 to 350 feet. The effective seeding distance is so limited on unshaded natural seedbeds on north aspects and on south aspects regardless of the seedbed conditions that the expectation of natural restocking in a reasonable period of time with clearcutting, is not a realistic option.
Citation
Alexander, Robert R. 1986. Engelmann spruce seed production and dispersal, and seedling establishment in the central Rocky Mountains. Gen. Tech. Rep. RM-GTR-134. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station. 9 p.