University of California

Exclosure size affects young blue oak seedling growth


Ralph L. Phillips
Neil K. McDougald
Edward R. Atwill
Doug UC Davis

Authors Affiliations

R.L. Phillips was Range/Natural Resources and Livestock Advisor, UC Cooperative Extension (UCCE), Kern and Tulare counties (now retired); N.K. McDougald is Area Watershed Management Advisor, UCCE Madera and Fresno counties; E. R. Atwill is Professor of Environmental Animal Health and Medical Ecology, School of Veterinary Medicine, UC Davis; D. McCreary is Area Natural Resource Specialist, Sierra Foothill Research and Extension Center, Browns Valley. Melvin George, Cooperative Extension Specialist, Department of Plant Sciences, UC Davis, served as Guest Associate Editor for this article.

Publication Information

Hilgardia 61(1):16-19. DOI:10.3733/ca.v061n01p16. January 2007.

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Blue oak, a tree native only to California, is notoriously slow-growing, and its low regeneration rate has prompted concern about the species' future survival in some areas of the state. We studied the use of fencing (exclosures) to protect seedlings from herbivores and promote faster growth. Placing exclosures 2 and 4 feet in diameter around blue oak seedlings increased their height and canopy area when compared to a control without exclosures. The 4-foot exclosures increased growth (height and canopy area) compared to the 2-foot exclosures. It appeared that exclosures reduced damage from both wild and domestic herbivores, resulting in accelerated growth rates.


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Phillips R, McDougald N, Atwill E, UC Davis D. 2007. Exclosure size affects young blue oak seedling growth. Hilgardia 61(1):16-19. DOI:10.3733/ca.v061n01p16
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