A Canker Disease of Abies concolor Caused by Nectria fuckeliana. Mark E. Schultz, Former Graduate Research Assistant, Department of Plant Pathology, University of California, Berkeley 94720. John R. Parmeter, Jr., Professor, Department of Plant Pathology, University of California, Berkeley 94720. Plant Dis. 74:178-180. Accepted for publication 2 October 1989. Copyright 1990 The American Phytopathological Society. DOI: 10.1094/PD-74-0178.

A canker disease of Abies concolor caused by Nectria fuckeliana killed suppressed trees and cankered more vigorous trees, mainly in overstocked stands. Inoculations consistently showed that N. fuckeliana isolated from cankers caused the disease. Commonly isolated nonsporulating fungi and the fungus Ascocalyx tenuisporus (fruiting on the margins of cankers) occasionally caused small cankers in inoculation tests. Perithecia of N. fuckeliana were produced on bark associated with inoculations. On vigorous trees, most of the cankering occurred within 1–2 yr after inoculation; calluses then grew over the wounds. On suppressed trees, cankering either killed trees within a year or resulted in slowly expanding lesions. N. fuckeliana was found in overstocked stands of predominantly white fir in northern California and southern Oregon.