We hypothesized that in the oligotrophic, acid soils of the New Jersey Pine Barrens, where native diversity and invasability appear to be low, the weathering of concrete block construction material over time has reduced resistance to plant species' invasion by reducing soil acidity. We also sought to determine whether alien species' success in disturbed Pine Barrens soil differs from that of the non–Pine Barrens North American plant species whose presence in the region is associated with anthropogenic soil disturbance. In the field, species richness of native Pine Barrens species, non–Pine Barrens species, and alien species was determined along with current-year aboveground biomass production and soil pH along transects extending from concrete block buildings and from paired control transects without concrete block buildings. Soil inorganic nitrogen was measured near and far from buildings. Additionally, a pot study using native soil amended with ground concrete was conducted to determine its effect on pore-water pH. Richness was significantly greater near buildings, with alien species concentrated within 6 m of buildings. Alien plant biomass was greater within 3 m of buildings than farther along the transects; however, productivity along the transects did not vary. Soil pH was elevated within 7.5 m of buildings and soil nitrate concentration was greater near buildings. The ground-concrete soil amendments were found to significantly elevate pore-water pH. We conclude that disturbed habitats with acid soil conditions possess a degree of ecosystem resistance to alien plant species establishment. However, this may be overcome by raising the soil pH.