Types

• Cytospora canker is caused by the fungus Cytospora kunzei and is severe in spruce trees. This fungus damages evergreens by entering through wounds, and forms cankers on the tree. Root rot diseases are common in evergreens, but are difficult to see because they affect roots beneath the soil. Root rot diseases are caused by fungi and are a serious threat to evergreens. While sooty mold is unsightly, it is not usually a threat to plant health. Sooty mold is a fungal disease caused by insect infestation.
  
  

Symptoms

• The symptoms associated with Cytospora canker include cankers, bark decay, oozing resin, dead foliage, dead limbs and black fruiting structures on tree bark. Root rot diseases cause dieback, stunting, needle discoloration and decline in tree health, states North Dakota State University. Evergreens with sooty mold develop a black fungus on all parts of evergreens.
  
  

Control

• Removing infected branches helps control fungal disease. Avoid wounding trees during pruning because this gives fungi easy tree access. Fungus caused by insects, such as sooty mold is controlled by eliminating the causative insect.