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The invasive feral swine (Sus scrofa) is a species that creates soil disturbances vastly different from any native omnivore in southern grasslands in the United States. Large soil disturbances are known to create opportunities for weedy and non-native species and may favor disturbance-adapted plants. In a long-term plant diversity experiment (2002-present) aimed at investigating season of burn and nutrient addition on plant community composition and productivity, composition had been monitored in 48 permanent plots since 2002 and plots were not impacted by feral swine until February 2012 when swine breached the fence and rooted in half of the permanent plots.  Our objectives were to 1) assess preference of feral swine for season of burn and nutrient addition and 2) examine the impacts of feral swine rooting on wet prairie vegetation. Feral swine avoided recently burned plots and rooted significantly more in nitrogen addition plots. In rooted plots, we observed a large increase in cover of redroot, (Lachnanthes caroliana), a plant known as a poisonous forage. Of the 2,459 m2 rooted by swine, 92% of the area was covered by a dense monoculture of redroot in less than 5 months. In rooted plots, there was on average an additional 40% cover of redroot and a reduction of 20% cover in the dominant bunchgrass whereas there were only slight changes in non-rooted plots from the prior year's species composition.  Composition in rooted plots was substantially different from unrooted plots. Feral swine disturbance significantly alters plant composition in wetland communities and thus changes the array of ecosystem services provided by these important ecosystems.  Wet prairies dominated by bunchgrasses provide valuable forage during the dry season; an ecosystem service that is compromised when impacted by feral swine.  A comprehensive understanding of feral swine impacts on vegetation and ecosystem services is critical for rangeland management.