Published online by Cambridge University Press: 12 June 2017
Survival of foxtail grass in undisturbed sites was tested in a 4-yr study of robust white foxtail (Setaria viridis var. robusta-alba Schreiber), robust purple foxtail (Setaria viridis var. robusta-purpurea Schreiber), giant green foxtail [Setaria viridis var. major (Gaud.) Posp.], yellow foxtail [Setaria lutescens (Weigel) Hubb.], and giant foxtail (Setaria faberi Herrm.). Regardless of taxa seeded, giant foxtail dominated the stand with small amounts of yellow foxtail in the fourth year. Although the foxtail taxa stands corresponded to the taxa seeded in the first year of growth, robust white foxtail, robust purple foxtail, and giant green foxtail completely or nearly disappeared within 4 yr of having been seeded alone or with other taxa, and generally sooner when mixed with giant foxtail. Because of the rapid dominance of giant foxtail, the robust white foxtail, robust purple foxtail, and giant green foxtails are not likely to become a source of seed for infestation from fencerows to production fields.