Grass competition and establishment of native species from forest soil seed banks

Abstract

Three pioneer plant communities - a reclamation mix of Festuca arundinacea (tall fescue), Eragrostis curvula (weeping lovegrass), Lolium sp. (ryegrass) and Lespedeza cuneata (sericea lespedeza), a native species community derived from a forest topsoil seed bank, and a combination of native species plus the reclamation mix - were established on a thin layer of topsoil over mine spoils in microplots. The seed bank produced 84 taxa, including 5 tree species, 7 shrubs or woody vines, 14 grasses and 53 forbs identifiable at least to genus. The seedbank treatment produced the greatest aboveground biomass. Adding seed of reclamation species to the seed bank resulted in a community which had less total biomass, less total biomass in native species and fewer established native species with lower populations and biomass than the native species community without reclamation species. Forest topsoil seedbank materials as a propagule source could significantly increase the diversity and productivity of a pioneer community on surface mine spoils even in combination with reclamation species.