Elytroderma Disease Reduces Growth and Vigor, Increases Mortality of Jeffrey Pines at Lake Tahoe Basin, California

摘要

A disease of Jeffrey pines Pinus jeffreyi at Lake Tahoe Basin, California, caused by Elytroderma disease (Elytroderma deformans) was studied for 7 years after a severe outbreak of the fungus in 1971. Among 607 Jeffrey pines on six plots, about one-half were heavily infected and about one-half were moderately or lightly infected in 1971. No uninfected trees were observed. During the 7-year study, about one-half of the trees remained unchanged in vigor, disease intensity, or both, and about one-half decreased in vigor, became more heavily infected, or both. Of the original 607 trees studied, nearly one-third died before 1978.