Plant Profile: Setaria pumila

Yellow Foxtail is a summer annual grass known for its weedy nature. It typically thrives in disturbed environments such as gravelly riverbanks, vacant lots, lawns, grassy strips along roads and railways, as well as fields and pastures. While it is rarely found in undisturbed natural habitats, it flourishes in sunny locations with moist to slightly dry conditions.

This particular variety of foxtail is easily identifiable due to its yellow bristles on immature spikelets, the number of bristles at the base of each spikelet, and its upright raceme blooms, distinguishing it from other types that feature green or purple bristles, fewer bristles at the base, and drooping panicle blooms.

The flat leaf sheaths can grow up to 8 inches long and may appear in shades ranging from green to a greyish-blue. Atop these sheaths sits a 5-inch raceme of florets. The immature spikelets are glossy green with yellow bristles, which turn tawny during blooming, and the entire spike takes on a light tan color when fully mature.

This self-seeding plant has a fibrous root system.

In terms of pests and diseases, Yellow Foxtail can be particularly aggressive, especially in disturbed areas.