How to Identify Northern Corn Leaf Blight
Prompt detection of NCLB is vital for effective control. NCLB manifests as long, elliptical, grey-green or tan lesions on the leaves. These lesions can vary from 1 to 6 inches long and about 1/2 to 3/4 inch wide. As the disease advances, the lesions darken to tan or gray and may appear slightly fuzzy due to the presence of fungal spores.
The first hints of NCLB typically surface after silking. Early symptoms include small, diamond-shaped lesions on the lower leaves. As the disease advances, these lesions elongate and adopt a more elliptical shape.