A proposed mechanism for plant invasions is modification of the soil in ways that enhance the growth of the invader relative to native species, but, to date, few clear examples have been documented. Two greenhouse experiments were conducted to test how the invader and several natives responded to field soil with a history of either high invader (sericea) or native plant abundance. Both experiments detected decreased biomass for several of the native species when grown with sericea while sericea had increased growth in soils with a history of sericea plants depending on water/neighbor identity. These results suggest that positive soil feedbacks may partially explain the invasive success of sericea in the Great Plains.