slender wild oat

Avena barbata is a species of wild oat known by the common name slender wild oat. It has edible seeds. It is a diploidized autotetraploid grass (2n=4x=28). Its diploid ancestors are A. hirtula Lag. and A. wiestii Steud (2n=2x=14), which are considered Mediterranean and desert ecotypes, respectively, comprising a single species. A. wiestii and A. hirtula are widespread in the Mediterranean Basin, growing in mixed stands with A. barbata, though they are difficult to tell apart.

This is a winter annual grass with thin tillers (stems) growing up to 60 to 80 centimeters in maximum height, but known to sometimes grow taller. The bristly spikelets are 2 to 3 centimeters long, not counting the bent awn which is up to 4 centimeters in length. Avena barbata largely reproduces by selfing in natural populations, with very low rates of outcrossing.