The Corylus Cornuta Var. Californica is commonly known as the California Filbert, California Hazel as well as California Hazelnut.
The accepted scientific name for California hazelnut is Corylus cornuta Marsh. var. californica (A. DC.) Sharp . The genus Corylus comprises 15 species, most of which occur in Asia. Beaked hazelnut (Corylus cornuta) is the only species native to the United States . Beaked hazelnut is distributed across North America. California hazelnut is the Pacific Coast entity of the species ; beaked hazelnut is a shrub occupying the eastern range of the species . There are two recognized forms of California hazelnut :California hazelnut occurs in California, Oregon, Washington, and British Columbia . In California it occurs along the Coast Range from Santa Cruz County northward along the coast to Del Norte County, eastward through Siskiyou County, and southward in the Sierra Nevada to Tulare County . In Oregon and Washington it occurs mostly west and occasionally east of the Cascades . In British Columbia it occurs on the lower mainland and on Vancouver Island . Intermediate forms of C. cornuta var. californica x C. cornuta var. cornuta may occur in the Fraser Canyon and Columbia Forest Region of British Columbia . Corylus cornuta var. californica forma glandulosa is frequently found along the Pacific Coast. It is more frequent than C. cornuta var. californica forma californica on southern Vancouver Island but becomes scarcer inland .Published classifications listing California hazelnut as a dominant in plant associations (pas) or community types (cts) are presented below: Location Classification Authority OR: Willamette Valley forest cts Thilenius 1968 c Cascades forest pas, cts Dyrness and others 1974 Mary's Peak Watershed forest cts Anderson 1969 Mary's Peak Watershed forest cts Anderson 1967 s OR: Cascade Mountain Province forest pas Atzet and McCrimmon 1990Some of the information provided here is attributed to:Zimmerman, Mary Lou 1991. Corylus cornuta var. californica. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). , available at the USDA Fire Effects Information System (FEIS) website