Regeneration alternatives for upland white spruce after burning and logging in interior Alaska

R.V. Densmore; G.P. Juday; J.C. Zasada

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USGS · 70021968

Regeneration alternatives for upland white spruce after burning and logging in interior Alaska

R.V. Densmore·G.P. Juday·J.C. Zasada

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Abstract

Site-preparation and regeneration methods for white spruce (Picea glauca (Moench) Voss) were tested near Fairbanks, Alaska, on two upland sites which had been burned in a wildfire and salvage logged. After 5 and 10 years, white spruce regeneration did not differ among the four scarification methods but tended to be lower without scarification. Survival of container-grown planted seedlings stabilized after 3 years at 93% with scarification and at 76% without scarification. Broadcast seeding was also successful, with one or more seedlings on 80% of the scarified 6-m2 subplots and on 60% of the unscarified subplots after 12 years. Natural regeneration after 12 years exceeded expectations, with seedlings on 50% of the 6-m2 subplots 150 m from a seed source and on 28% of the subplots 230 m from a seed source. After 5 years, 37% of the scarified unsheltered seed spots and 52% of the scarified seed spots with cone shelters had one or more seedlings, but only 16% of the unscarified seed spots had seedlings, with and without funnel shelters. Growth rates for all seedlings were higher than on similar unburned sites. The results show positive effects of burning in interior Alaska, and suggest planting seedlings, broadcast seeding, and natural seedfall, alone or in combination, as viable options for similar sites.

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R.V. Densmore, G.P. Juday, J.C. Zasada. 1999. Regeneration alternatives for upland white spruce after burning and logging in interior Alaska. https://pubs.usgs.gov/publication/70021968

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