Spot Anthracnose of Dogwood or Elsinoë Leaf spot

Key Points

• The fungus Elsinoë corni causes a spot anthracnose primarily on Cornus florida. This disease should not be mistaken for another more serious dogwood disease called dogwood anthracnose caused by the fungus Discula destructiva. 
• The disease can infect flower bracts, leaves, and fruit.  The fungal lesions are about 1/8 of an inch across with a tan center surrounded by a reddish-purple border.
• These spots can be numerous and often fall out producing a ragged leaf appearance.
• The fungus overwinters on twigs and infections begin as new growth emerges in the spring.
• This disease is worse in wet weather.

Management  

• Plant cultivars resistant to spot anthracnose.
  
  
• Rake and discard symptomatic foliage.
  
  
• Since disease severity is sporadic depending on how wet the spring season is routine fungicide applications are not recommended.
  
  
• Fungicides will not cure visible symptoms. If spot anthracnose is severe on young trees, they can be protected with a registered fungicide applied in the spring at bud break followed by additional sprays every 7 - 14 days until leaves are fully expanded.

Additional Resources

• Diagnosing Problems of Flowering Dogwood
• Flowering Dogwood Trees: Selection, Care, and Management of Disease Problems
• Dogwood Insect Pests: Identification and Management