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