These spots expand and later turn light tan. Lesions are irregularly shaped and range from elliptical to very long and narrow. The black speckles are fungal fruiting bodies. The black fruiting bodies can usually be seen without the aid of a magnifying glass. The disease begins on the lower leaves and gradually progesses up to the flag leaf.
Leaf sheaths are also susceptible to attack.
In wet years, the speckled leaf blotch fungus can move to the the heads and cause glume blotch symptoms. Brown lesions appear randomly on the glumes and awns. These lesions bleach to light tan and often contain the typical black speckles that are the fruiting bodies of Septoria tritici . The fungal fruiting bodies are often seen embedded in the lesions on the awns. The glume blotch phase appears to cause significant yield loss, but this is difficult to measure.