Red Star Rust

Red star rust (also known as Japanese apple rust or lipstick rust) is a type of Gymnosporangium rust. This plant disease is particularly concerning because of its potential negative impact in commercial apple production. 

Rhizosphaera Needle Cast

Rhizosphaera needle cast is the most common disease of Colorado blue spruce in Wisconsin, and can also affect other conifers. This factsheet covers identification and management of this disease.

White Pine Blister Rust

White pine blister rust is a serious, tree-killing disease of eastern white pine and its close relatives. Learn how to manage this disease in this factsheet.

Phomopsis Tip Blight

Phomopsis tip blight is one of the most common fungal disease of conifers, including junipers, arborvitae, firs, larch and jack pine. This factsheet describes symptoms and management of this tip blight.

Cytospora Canker

Cytospora canker is one of themost common fungal diseases of Colorado blue spruce, and can also affect other spruce and firs. Learn about symptoms and management in this factsheet.

Diplodia Shoot Blight and Canker

Diplodia shoot blight and canker is one of the most common fungal diseases of Austrian pine in Wisconsin, and can also affect other pines as well as other conifers including cedars, cypresses, firs, junipers and spruces. Learn more here.

Dothistroma Needle Blight

A common needle blight, Dothistroma can affect over 30 species of pine trees, especially Austrian pine. Learn symptoms and management of this disease in this facthsheet.

Swiss Needle Cast

Swiss needle cast is a fungal disease of Douglas fir. Symptoms and management of this disease are described in this factsheet.

Weir’s Cushion Rust of Spruces

Weir’s cushion rust is a needle disease that disfigures and reduces growth of spruce trees. Learn to identify and avoid problems with Weir’s cushion rust in this factsheet.

Phytophthora Root Rot of Christmas Trees

Phytophthora root rot is a common disease of Christmas trees including Douglas-fir, balsam and true firs (e.g., Fraser, balsam and Canaan), spruces, and pines. This fact sheet covers symptoms and management.

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