The response of semi-arid vegetation assemblages following the abandonment of mining towns in south-western Montana

Abstract

Abandoned mining towns provide an excellent opportunity to examine long-term vegetation recovery processes. Analysis of data collected in five ghost towns in semi-arid south-western Montana indicated considerable differences remain after 45–77 years of recovery. Two measures of vegetation recovery, introduced grass cover and species richness, differed markedly between undisturbed sites and disturbed sites at four of the towns. Disturbances favoured the invasion of introduced grasses and greater species diversity. At the fifth town, the driest location, the presence of a native sod grass, Bouteloua gracilis , which can withstand severe disturbances, apparently inhibited the establishment of non-native species, thereby hastening the recovery process.