What Are Cytospora Canker?
This canker disease (caused by a fungus) occurs most frequently on stressed spruces, or those over the age of 15 years. Although the disease seldom kills the plant outright, it destroys the beauty of the tree by killing branches, especially lower branches. Fungicides are not effective in controlling this disease. Root zone fertilization and watering will improve plant vigor and help ward off the fungus.
Prevention of Cytospora Canker:
- Dead and dying branches should be removed as soon as possible.
- Sterilize pruning tools between each cut with denatured alcohol or a 10% solution of bleach and water to prevent spreading the disease.
- Avoid injury to tree limbs.
- Follow a regular program of fertilization and watering to promote vigorous growth.