foxtail (Setaria) species-group
The weedy Setaria species (giant, green, yellow, knotroot, and bristly foxtail) compose one of the worst weed groups interfering with world agriculture and in other disturbed and managed habitats. These species, together with their crop counterparts (foxtail millet, korali), form the foxtail species-group (spp.-gp). Five successive waves of Setaria spp. invasion from preagricultural times to the present have resulted in widespread infestation of the disturbed, arable, temperate regions of the earth. These invasions have resulted in considerable economic and environmental costs.