Cherry Leaf Spot: A Common Disease in Cherry Trees
What is Cherry Leaf Spot?
Cherry leaf spot is a fungal disease that affects cherry trees, particularly tart cherry crops. It is caused by the fungus Blumeriella jaapii, which was formerly known as Coccomyces hiemali. Cherry leaf spot is a common disease that can cause defoliation and reduce fruit yield if left untreated.
Symptoms of Cherry Leaf Spot
The first symptom of cherry leaf spot is the appearance of small, circular spots on the leaves. These spots are initially red to purple in color and measure about 1/8 to 1/4 inch in diameter. As the disease progresses, the spots become rusty brown to brown and may develop a whitish downy material in their centers. The spots may also drop out, creating small holes in the leaves.
Causes of Cherry Leaf Spot
Cherry leaf spot is caused by the fungus Blumeriella jaapii. The fungus overwinters on infected leaves that have fallen to the ground. In the spring, when temperatures warm and there is ample rainfall, the fungus produces spores that are spread by wind and rain to infect new leaves.
How to Prevent Cherry Leaf Spot
There are several steps you can take to prevent cherry leaf spot:
- Remove and destroy infected leaves from the ground in the fall.
- Apply a fungicide in the spring, just as the leaves are beginning to bud.
- Avoid overhead watering, as this can spread the fungus.
- Prune trees to improve air circulation and reduce humidity.
How to Treat Cherry Leaf Spot
If your cherry tree has already been infected with leaf spot, there are several treatment options available:
- Apply a fungicide according to the manufacturer’s instructions.
- Remove and destroy infected leaves.
- Prune trees to improve air circulation and reduce humidity.
- Water trees at the base to avoid wetting the leaves.
Impact of Cherry Leaf Spot on Fruit Yield
Cherry leaf spot can have a significant impact on fruit yield. Severe infections can cause defoliation, which reduces the tree’s ability to produce fruit. The disease can also cause the fruit to be smaller and less flavorful.
How to Diagnose Cherry Leaf Spot
Cherry leaf spot can be diagnosed by its characteristic symptoms, such as the presence of small, circular spots on the leaves. It is important to distinguish cherry leaf spot from other fungal diseases that can affect cherry trees, such as powdery mildew and anthracnose.
Distinguishing Cherry Leaf Spot from Other Fungal Diseases
Cherry leaf spot can be distinguished from other fungal diseases by its symptoms and the time of year when it occurs. Powdery mildew, for example, causes a white powdery growth on the leaves, while anthracnose causes large, brown lesions on the leaves and fruit. Cherry leaf spot is most active in the spring and early summer, while powdery mildew and anthracnose can occur at any time during the growing season.
Management of Cherry Leaf Spot in Orchard Settings
In orchard settings, cherry leaf spot can be managed through a combination of cultural practices and chemical treatments. Cultural practices, such as removing infected leaves and pruning trees to improve air circulation, can help to reduce the spread of the disease. Chemical treatments, such as fungicides, can be used to control the fungus and prevent infection.
Conclusion
Cherry leaf spot is a common disease that can affect cherry trees. By understanding the symptoms, causes, and treatment options for cherry leaf spot, you can help to protect your trees and ensure a healthy harvest.
