Yellow Foxtail (Setaria glauca)
Yellow foxtail is a warm-season annual that reproduces by seeds that germinate at temperatures between 68 and 95°F. Yellow foxtail forms a coarse, upright or prostrate, bunch-type grass. It usually branches at the base and may root at lower nodes. Growing up to 4 feet tall, yellow foxtail emerges from a shallow, fibrous root system and normally has flattened stems that are reddish near the base. Leaves of yellow foxtail are flat, smooth, and with margins that are somewhat rough. They grow 2 to 12 inches long and up to 1/2 inch wide. Twisted or spiraled hairs, 1/8 inch long, usually appear near the base on the upper surface. The sheath is flattened with a prominent midvein. The flowers are cylindrical, dense, bristly, and erect. They are 2 to 5 inches long, yellow, spike-like, and appear June to September.
Occurrence
Yellow foxtail occurs in moist, fertile soil during the mid to late growing season and is often found in spring establishments, open turf, or bare spots.
Non-Chemical Control
To control yellow foxtail without chemicals, mechanically remove or hand pull. Maintain turf density and health through proper culture; avoid close mowing and summer fertilization.
Chemical Control
Apply preemergence herbicides one to two weeks prior to germination in the late spring or summer; use postemergence herbicides when weeds are small.
