Yellow foxtail Setaria pumila (Poir.) Roem&Schult.
Family: Poaceae
Life cycle: Annual
Native range: Introduced from China.
Habitat: Crop fields, disturbed areas
General description: Erect growth habit up to four feet tall. Plant has a hairy ligule, the majority of leaf and sheath are glabrous, but there are numerous relatively long hairs (up to ½”) at the base of the leaf blade. Yellow foxtail seeds are larger than green and giant foxtail and are systematically arranged on spike. Yellow awns on seeds are the source of name. Stem is slightly flat on mature plants.
Key ID traits: Hairy ligule. Sparse, long hairs at the base of leaf blade, otherwise leaves are hairless.
Similar species: Green and yellow foxtail.
Miscellaneous: More tolerant of mowing than the other foxtails, so more common in hay fields, field alleyways, and found occasionally in poorly-managed turf. Yellow foxtail also is more tolerant of many postemergence herbicides than the other foxtails, and thus is more common in crop fields where total post programs have been used.