An Experimental Approach to the Reclamation of a Limestone Quarry Floor: The First Three Years

Abstract

‘Three-inch [7.5 cm] crusher-run’ limestone proved entirely suitable as a substratum for the rapid establishment of pioneer vegetation on a quarry floor, but only with the addition of fertilizers. A manure derived from sewage and an NPK fertilizer mixture proved suitable additives. A grass variety (Festuca rubra var. fallax Hack.) was sown, and became established on the substratum treated with either additive. Immigrant mosses soon became dominant in a grass/moss community on the manured substratum, whilst F. rubra retained its ascendancy on the NPK-treated material. The moss-dominated community was not attractive to Rabbits, whereas the grass-dominated community proved attractive to these animals which are accepted as beneficial for conservation in this particular context.Further observations are required to assess (a) whether the by-passing of a cryptogamic stage in the prisere encouraged by the NPK mixture is a worthwhile objective, (b) whether the observed dominance of mosses encouraged by manure will be broken by F. rubra, and (c) whether the establishment of desirable immigrant species occurs differentially between the treatments. Meanwhile a perceptible degree of rehabilitation within three years may be claimed as a result of treatments producing a total plant cover of between 40% and 70%.