There are 2 types of lesion - a small spot and a large blotch.
The small spot is circular, dark brown and 2-5 mm wide with a light centre and little of no yellowing around the edges. The centres of the spots often rot away leaving a hole in the leaf.
The large, brown blotches may expand to cover the leaf blade and are surrounded by a yellow halo that is usually wider at the ends than the sides. The centre of the lesion may die and leave a hole in the leaf. The blotches expand and eventually cover the whole leaf. In crops many of the leaf tips are dead and withered.
Thin, black, spiky, spore producing fungal structures up to 3-4 mm long can often be seen on the ground growing from infected crop and grass residues and seed.
Barley, Barley Grass, Brome Grass and other grasses.
Occurs on most grass species and is common on Bromes (Bromus spp.).