Longevity of Foxtail Taxa in Undisturbed Sites

Abstract

Survival of foxtail grass in undisturbed sites was tested in a 4-yr study of robust white foxtail (Setaria viridisvar.robusta-albaSchreiber), robust purple foxtail (Setaria viridisvar.robusta-purpureaSchreiber), giant green foxtail [Setaria viridisvar.major(Gaud.) Posp.], yellow foxtail [Setaria lutescens(Weigel) Hubb.], and giant foxtail (Setaria faberiHerrm.). 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.