Crabgrass (Digitaria sanguinalis)—Grant Heilman Photography

Any of about 300 species of grasses in the genus Digitaria, especially D. sanguinalis or the slightly shorter D. ischaemum (smooth crabgrass). D. sanguinalis has long hairs covering its leaves and five or six spikelets; D. ischaemum has no hair and only two or three spikelets. Both are natives of Europe that became widely naturalized as weeds in North America. They and a few closely related species are very troublesome in lawns and fields. One species, Arizona cottontop (D. californica), is a useful forage grass in the American Southwest.

This entry comes from Encyclopædia Britannica Concise.
For the full entry on crabgrass, visit

Seen & Heard

What made you look up crabgrass? Please tell us what you were reading, watching or discussing that led you here.