Canker diseases result in the formation of distinct, sunken lesions on the bark of woody plants. Cankers restrict water and nutrient movement and may ultimately lead to branch dieback and tree death.
Sieridium canker is a serious disease, occurring on Oriental arborvitae throughout Kansas.
The symptoms for this disease are frequently confused with winter-related injuries. Seiridium canker , caused by the fungus Seiridium unicorne , occurs on Oriental arborvitae, bald-cypress, Arizona, Italian and Leyland cypresses, and occasionally junipers. Symptoms of the disease are similar to Botryosphaeria canker. Elongated, flattened cankers form on small branches and main stems. Bleeding or resin formation in cankers is common.