Apiognomonia erythrostoma

Leaves will show yellow to red leaf spots not restricted by leaf veins, often coalescing and turning brown. Affected leaves readily wither, curl up, and fall prematurely in the summer or remain on the tree through winter. Pycnidia, containing filiform conidia, form in the spots during the summer, and beaked perithecia develop in the leaves on the tree and on the ground in the autumn.