Shot Hole Disease – Definition & Detailed Explanation – Tree Diseases and Pests Glossary

What is Shot Hole Disease?

Shot Hole Disease is a fungal infection that affects a variety of trees, causing circular or irregularly shaped holes to form on the leaves. The disease is caused by several different species of fungi, including Wilsonomyces carpophilus and Coryneum beijerinckii. These fungi infect the leaves of trees, causing them to develop small, dark spots that eventually fall out, leaving behind the characteristic shot holes.

What are the symptoms of Shot Hole Disease?

The most common symptom of Shot Hole Disease is the formation of small, circular or irregularly shaped holes in the leaves of infected trees. These holes can range in size from a few millimeters to several centimeters in diameter. In addition to the shot holes, infected leaves may also develop yellow or brown spots, wilting, and premature leaf drop. In severe cases, the disease can cause defoliation and weaken the overall health of the tree.

How does Shot Hole Disease spread?

Shot Hole Disease spreads through the release of fungal spores from infected trees. These spores are carried by wind, rain, or insects to healthy trees, where they can germinate and infect new hosts. The disease is most commonly spread during periods of warm, wet weather, when conditions are optimal for fungal growth and spore dispersal. Once a tree is infected, the disease can spread rapidly throughout the canopy, causing widespread damage.

How can Shot Hole Disease be prevented?

There are several steps that can be taken to prevent Shot Hole Disease in trees. One of the most important prevention methods is to maintain good overall tree health through proper watering, fertilization, and pruning. Trees that are stressed or weakened are more susceptible to fungal infections, so keeping them healthy can help prevent the disease from taking hold. Additionally, removing and destroying infected leaves can help reduce the spread of the disease to other trees in the area.

How is Shot Hole Disease treated?

There are several methods that can be used to treat Shot Hole Disease in trees. Fungicides can be applied to infected trees to help control the spread of the disease and protect healthy foliage. Pruning and removing infected branches can also help reduce the severity of the infection and prevent it from spreading further. In severe cases, where the tree is heavily infected and showing signs of decline, it may be necessary to remove and replace the tree to prevent the disease from spreading to other trees in the area.

What are the common trees affected by Shot Hole Disease?

Shot Hole Disease can affect a wide range of trees, including fruit trees such as peach, cherry, and plum, as well as ornamental trees like dogwood, holly, and photinia. These trees are particularly susceptible to the disease due to their thin leaves and high moisture content, which create ideal conditions for fungal growth. In addition to these common hosts, Shot Hole Disease can also infect a variety of other tree species, so it is important to be vigilant and take steps to prevent and treat the disease in all trees on your property.