Shot hole disease is a fungus that appears as spots on leaves, fruit, twigs, and flowers of almond trees. Lesions on flowers and twigs are difficult to find. Lesions on leaves begin as red specks that enlarge into spots with tan centers and purple margins. The fruiting structure appears as a small dark speck in the center of the spot when the fungus sporoulates. Spots on young leaves fall out, leaving a whole, but lesions remain on older leaves.
Spots on fruit are found on the upper surface of the fruit and are small with purplish margins and are slightly corky and raised.
Manage shot hole fungus by monitoring orchards in the fall and spring for lesions and fruiting structures. Fruiting structures can be seen with a hand lens. If fruiting structures exist in leaf lesions in the fall, shot hole development is of great risk in the next spring.
For treatment and more information about shot hole disease, click here.