Acroptilon repens is an invasive weed in North America but also causes problems in disturbed habitats in its native range in Asia. in order to test the effect of simulated biological control and soil disturbance on established A. repens patches and the competing vegetation, two levels of shoot clipping as well as soil tillage were imposed on A. repens patches in an undisturbed meadow and at two fallowland sites in the native range of the weed. At the meadow site, 2 years of partial clipping of shoots and of soil tillage had no influence on A. repens performance, while soil tillage significantly reduced the aboveground biomass of the competing vegetation. At the fallowland sites, which had been continuously cultivated for several years prior to the experiment, A. repens shoot density, biomass and number of seed heads were significantly higher in the undisturbed control than in the tillage plots. The total number of seed heads per unit area increased with shoot density up to 200 shoots m. These results indicate that A. repens has considerable regrowth capacities that allow established patches to tolerate substantial losses of above-ground biomass and that the competitive ability of A. repens is favoured both when soil disturbance is imposed on previously undisturbed sites, as well as when repeated soil disturbance is abandoned. The only promising nonchemical herbicide-based approach to reduce the competitive ability and seed Output Of A. repens appears to be a long-term management that enhances the interspecific plant competition by reducing soil disturbance and selectively damaging A. repens.