On leaves, initial symptoms of stagonospora nodorum blotch appear as small dark-brown to chocolate-colored lesions, usually on the mid-rib of older leaves that are close to the soil surface. These lesions typically have a yellow halo as a result of diffusible toxins produced by the pathogen. The lesions expand and become oval (lens-shaped) or elliptical with dark-brown centers. A mature stagonospora nodorum blotch lesion has a grayish-white center with a dark-brown periphery. In severe epidemics, lesions can coalesce to cover the whole leaf, resulting in the death of the leaf tissue. On the glumes and awns, symptoms appear as tan to brown-colored lesions. The lesion on a glume typically starts at the tip of the glume and progresses downward. The pathogen can also produce dark-brown lesions on stems and nodes (hence the species name \"nodorum\") of wheat plants. Infected glumes lead to shriveled kernels that reduce grain quality and quantity.​​