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Extension > Garden > Yard and Garden > Lirula needle blight

Lirula needle blight

Michelle Grabowski - University of Minnesota Extension Educator
Cynthia Ash Kanner - former University of Minnesota Extension Specialist

Back to Diseases of spruce trees in Minnesota

Lirula

Photo by P.Hennon USDA FS
Bugwood.org

Lirula needle blight is caused by the fungus Lirula macrospora.

This disease can occur in Colorado blue spruce, Picea pungens, and white spruce, Picea glauca. White spruce, including Black Hills spruce, is the more susceptible species.

Identification

Biology

It takes several years for Lirula macrospora to complete its lifecycle. The fungus overwinters in infected needles on the tree. During late spring through midsummer infected needles release spores that spread in splashing and dripping rain to new needles. First year needles appear to be the most susceptible. On second year needles, a raised black line, which is a spore producing structure created by the fungus, forms on the midrib on the underside of the needle. Spores are released from these structures on third year needles.  

Management

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