Distribution and Characteristics of the Eastern Filbert Blight Epidemic in Western Oregon

Abstract

In October of 1986, eastern filbert blight (EFB), caused by Anisogramma anomala, was found in a hazelnut (Corylus avellana) orchard located in Oregon's Willamette Valley. This was the first detection of EFB within Oregon's principal hazelnut production area. Hazelnut plantings in nine Willamette Valley counties were surveyed in fall and winter during 1986-1990 to determine the prevalence and distribution of the disease. EFB was found at 326 of the 1,207 survey sites. Disease incidence and severity were greatest in the northeastern Willamette Valley (.)