Anthracnose fungi produce asexual spores (conidia) within pads of tissue (acervuli, on the upper or lower leaf surface and along veins or midribs), causing dark-brown to black spots within leaf spots and blotches

Discula campestris is one of several fungal pathogens responsible for maple anthracnose disease, and the maple leaves are the primary source of inoculum; however, infected shoots can also harbor the pathogen

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