Fluoride tolerance in grasses with particular reference to fluorspar mine waste

A bioassay experiment on fluorspar mine waste comparing the performance of the native waste populations and non-native populations of Festuca rubra suggested that the native plants grew better. In further experiments using solutions of sodium fluoride, percentage germination and root extension growth was greater in plants native to fluorspar sites. In a sand culture experiment, populations of Deschampsia cespitosa and Agrostis tenuis native to fluorspar sites showed a greater overall increase in dry weight in 9 weeks than did non-mine plant populations when watered with sodium fluoride solution. These experiments suggest that grass populations native to fluorspar sites have a certain degree of tolerance to the elevated fluoride concentations in the substrate. The ecological significance of this, with particular regard to reclamation, of these wastes, is difficult to assess at this time.