Onopordum L., cottonthistle, is a genus of plants in the thistle tribe within the Asteraceae. They are native to southern Europe, northern Africa, the Canary Islands, the Caucasus, and southwest and central Asia. They grow on disturbed land, roadsides, arable land and pastures. These plants propagate only by seed. The seed heads mature in mid-summer, releasing their seeds. The fruit is a glabrous achene, 4–6 mm long and with 4-50 ribs. The pappus consists of many rows of simple, fine to minutely rough hairs, united in a circular base.