Taxonomists describe panicles of green and yellow foxtail (Setaria viridis (L.) and S. glauca (L.) Beauv., respectively) as dense, contracted, narrow and cylindrical. However, a 6-y survey near Hays, Kansas documented inflorescences of green and yellow foxtail that were divided into two to four or more elongated segments. Those panicles were forked or digitate rather than a single compact cylinder. Anomalous panicles were always found on plants having several normal heads. Branched morphology was infrequent (<1 head in 10,000), but was observed in 1993 and 1995–1998. Before 1998 Kansas collections of foxtail specimens with abnormal panicles were limited to a 1600 × 3200 m area in central Ellis County. Observations during 1998 increased the known geographic distribution in Kansas to a 3200 × 3600 m area. Seed collected from branched panicles of both species and grown in greenhouse conditions did not produce plants with any aberrant inflorescences. Occurrence of deviant green or yellow foxtail panicles did not correlate with herbicide usage or drift.