Klemow, K. M. 2005. TREE INVASION ON RECLAIMED ANTHRACITE SURFACE MINES IN PENNSYLVANIA: REEVALUATING INHIBITION. Contributed paper: Ecological Society of America meeting. Abstract: Ecological Society of America Abstracts XXX.
Reclamation of mine-impacted lands often involves grading the land to a relatively smooth contour, and seeding with a grass / legume mix. Preliminary research conducted out of our lab suggested that dense ground cover produced as a result of a successful seeding program may inhibit subsequent woody plant colonization on reclaimed mine sites. As a result, succession to a more native forested ecosystem may be slowed. The purpose of this study was to expand the number of sites examined to determine whether the findings of the previous studies held for other sites. A poorly reclaimed site having <60% herbaceous ground cover averaged 43.6 tree seedlings / 625 m2 plot. In contrast, well-reclaimed sites having >80% ground cover averaged only 6.8 tree seedlings. Tree species richness was lower on plots with dense ground cover (1.5) than those with sparse cover (3.5 species). However, some individual plots with dense ground cover had relatively high stem densities from species like black locust (Robinia pseudoacacia) that reproduce clonally. Tree species that colonize via seed dispersal and seed germination proved to be rare on reclaimed sites with dense ground cover. Thus, current reclamation schemes may not completely inhibit woody colonization, but apparently do restrict the diversity of woody species able to colonize successfully reclaimed sites.