Wild oats is an annual weed, reproducing by seed. The seedling has a counter-clockwise leaf twist and no auricles. It has hairs on the leaf margins and a membranous ligule. In the mature plant, the stems are smooth, erect, and grow up to 150 cm (4 ft.) tall. The leaves are similar to tame oats. The head is an open panicle and the spikelets usually contain two to three florets. The panicle may contain up to 250 seeds, ranging from black, brown, grey, yellow, to white.
The seeds are hairy at the base and awned with a circular scar at the point of seed attachment. They can remain dormant in the soil for seven to eight years but most seeds germinate within two years. Warm, dry, fall conditions promote the loss of seed dormancy but dormancy can be induced again the following spring under wet soil conditions and low temperatures. Wild oats prefer cool weather and moist soil.
Wild oats in grain cause increased dockage.