We think that this is a combination of cold damage from the late frosts we had and anthracnose disease, which is worse in wet springs like we are having.
Most large shade trees will flush out new healthy leaves and be fine.
Here are some management options:
- In most cases, anthracnose leaf diseases on mature trees will not be a major problem threatening the health of the tree.
- The best management practices involve pruning and removal of dead twigs during the winter or dry summer months.
- Mature trees can be thinned for better air circulation throughout the canopy.
- Rake and remove infected fallen leaves in the fall and plant resistant varieties when available.
- It is generally not economical to spray large mature shade trees for anthracnose diseases nor is it effective once disease symptoms are noticeable.
- Young trees or newly planted trees may need fungicide sprays to prevent excessive leaf loss until they become established in the landscape.