Cytospora kunzei var. piceae
Cytospora canker (Cytospora kunzei var. piceae) is one of the most damaging bark diseases of spruce trees east of the Rocky Mountains. Many species are susceptible to this disease, but for the purposes of this protocol, cytospora on blue spruce (Picea pungens) will be discussed. Blue spruce is often sited incorrectly causing stress, which predisposes the tree to infection by the fungus. Cytospora rarely kills trees outright, but it makes them unsightly by killing branches and causing sap ooze from infected branch lesions.