Giant foxtail
June 11, 2015
Setaria faberi Herrm Poaceae (Grass family)
Life cycle
Erect summer annual.
Leaves
Leaves have dense short hairs on the upper surface. They are soft, rolled in the bud and up to 12 inches long. Leaf sheaths have hairs along the margins.
Ligule
Hairy
Stems
Erect, mostly 3- to 7-foot-tall stems are branched and clump-forming at the base. Stems are usually round but are occasionally flattened in cross section.
Flowers and fruit
The seedhead is a dense, cylindrical-shaped, foxtail-like panicle with green to purple bristles. Highly nodding seedheads are capable of producing large numbers of oval to egg-shaped, yellowish brown seeds.
Reproduction
Seeds.
Similar weeds
Green foxtail (S. viridis L.)
Differs by having leaves that are hairless and rough to the touch, shorter stature – reaching only three feet tall, erect to slightly nodding panicles.
Yellow foxtail (S. glauca [L.] Beauv.)
Differs by having long, wispy hairs on the upper leaf surface near the stem, a panicle with yellowish brown bristles and a yellow to light brown seedhead at maturity.