Anthracnose on maple
Anthracnose can cause large dark-brown blotches along the veins and between them; and leaves can be puckered or deformed. Anthracnose infections are common on lower limbs and on branches close to the trunk so that from a distance the trees look like the lower and inner branches have fewer and smaller leaves than the outer and upper branches.
Photo; Paul Bachi, University of Kentucky Research and Education Center, Bugwood.org anthracnose Discula spp. maple Acer spp.