Many studies have documented that patterns of species composition change after gap creation, but few have addressed the processes responsible for this change. The idea of competitive reduction, that disturbance removes biomass, reducing competitive intensity and allowing competitively inferior fugitive species to colonize, has been widely accepted but rarely tested. We suggest an alternative hypothesis, competitive change, in which changes associated with disturbance may act to alter the competitive hierarchy. Under these changed conditions, species characteristic of gaps may be competitively superior to species characteristic of undisturbed matrix areas. We quantified competitive response ability for survival and relative growth for three target species (Andropogon gerardii, a matrix grass; Coreopsis tripteris, a matrix forb; and Ratibida pinata, a forb characteristic of gaps) in undisturbed matrix vegetation and in soil mound disturbances in a northern Ohio prairie community. For survival, a weak competitive hierarchy developed following gap creation. In contrast, for relative growth, gap creation shifted a distinct competitive hierarchy to conditions of competitive equivalence. The com- petitive rankings for survival in gaps were opposite those for growth in matrix conditions, with Andropogon being superior in terms of survival and Coreopsis superior in terms of growth. Then, in a factorial design, we teased apart the effects of neighborhood (biomass re- duction, size structure, neighbor identity) and abiotic soil changes (mound formation) as- sociated with soil disturbance on these competitive interactions. Abiotic changes associated with mound formation, rather than neighborhood changes, were responsible for the devel- opment of the survival hierarchy and the loss of the growth hierarchy following gap creation. When hierarchies formed, matrix species were competitively superior to gap species, sup- porting the idea of competitive reduction. However, no one matrix species was consistently competitively superior, and under some conditions species were competitive equivalents, partially supporting the idea of competitive change. When disturbance creates conditions of physical stress, as in this case, trade-offs between growth and survival hierarchies may be important determinants of species response.