Comparative Rates of Western Juniper Afforestation in South-Central Oregon and the Role of Anthropogenic Disturbance

UNCG Author/Contributor (non-UNCG co-authors, if there are any, appear on document)
Paul A. Knapp, Professor (Creator)
The University of North Carolina at Greensboro (UNCG )
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Abstract: We examine changes in canopy cover for adult western juniper from the 1960s to 1994 in central Oregon using repeat aerial photography. We compare changes at four sites with a land-use history of minimal anthropogenic disturbance to changes on adjacent sites that have a disturbance history more typical of central Oregon rangelands. Canopy cover increased at all sites, but afforestation on sites with domestic livestock grazing was greater. The potential driving forces common to all sites include a long fire-free interval, early twentieth-century favorable climatic conditions, biological inertia, and atmospheric CO2 enrichment.

Additional Information

The Professional Geographer
Language: English
Date: 2003
afforestation, canopy-cover increases, repeat aerial photography, western juniper

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