hooked bristle grass

Setaria verticillata is a species of grass known by the common names hooked bristlegrass, rough bristle-grass and bristly foxtail. It is native to Europe, but it is known on most continents as an introduced species and often a noxious weed. It is a hardy bunchgrass which grows in many types of urban, cultivated, and disturbed habitat. It is a weed of many types of agricultural crops, growing in vineyards and fields. Herbicide-resistant strains have been noted.

This is an annual grass with decumbent or erect stems growing up to a meter long. The leaf blades are up to 25 centimeters long and have a long sheath around the stem. The inflorescence is a dense panicle up to 15 centimeters long which tapers at both ends. It contains many small spikelets and bristles. The bristles have tiny backwards-pointing barbs that help them hook onto clothing or animal fur, facilitating their dispersal.