Phomopsis Blight of Junipers - Juniper Tree Blight Disease

Glenn W. Peterson1 and C. S. Hidges, Jr.2
1Plant Pathologist, U.S. Department of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station, Lincoln, Nebr.
2 Plant Pathologist, U.S. Department of Agriculture, Forest Service, Pacific Southwest Forest and Range Experiment Station, Institute of Pacific Islands Forestry, Honolulu, Hawaii.

Phomopsis blight has been a serious problem for more than 75 years in nurseries producing juniper seedlings and grafts. Phomopsis juniperovora Hahn, the fungus causing this disease, is widespread in the United States (fig. 1).
Figure 1. States in which Phomopsis juniperovora is present.
Description
Losses have been most severe in seedling and transplant beds of eastern redcedar and Rocky Mountain juniper. (See cover photo.) Other junipers are susceptible, as are some species in the genera Chamaecyparis, Cupressus, and Thuja. Arizona cypress seedlings have been seriously damaged in some Southern States.

U.S. GOVERNMENT PRINTING OFFICE: 1982 - 378-632