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Disturbances such as pipelines, roads and well sites can function as corridors for seed dispersal and allow invasive species to establish. Over-time introduced or ruderal species may saturate the seed bank near the disturbance and eventually migrate into adjacent native grassland. Invasive species of potential concern in the mixedgrass prairie include cool-season grasses (Agropyron cristatum, Poa pratensis), noxious weeds (e.g. Sonchus arvensis) and escaped agronomics (Melilotus spp.). All these species can be highly competitive and alter their microenvironment, thereby facilitating further invasion and displacement of native plant species. We hypothesized that the presence and abundance of invasive plants, both above-ground and in the seed bank, will increase as a function of spatial distance from disturbance and time since pipeline construction. Pipelines were visually identified and sampled along transects oriented perpendicular to the pipeline at 15 varying distances. Spatial sampling intensity was high adjacent to the pipeline and decreased out to a distance of 55 m. Within each distance, 16 soil cores (3.25 cm wide x 6 cm deep) were removed and bulked, then placed in a greenhouse where emergent seedlings were identified and counted. In addition, cover of above-ground vegetation was assessed at every third transect. By comparing seed bank and vegetation composition we will identify the degree of similarity between the seed bank and current plant community, and evaluate how this relationship changes with distance from pipeline and age of the disturbance. Records of pipeline installation and reclamation may also identify practices that promote the conservation of native vegetation and minimize invasive species.