A Two‐Step System for Revegetation of Surface Mine Spoils

Abstract

AbstractA two‐step procedure for revegetating surface mine spoils was tested. It consists of: (i) establishment of a fast growing initial ground cover to minimize erosion, and (ii) chemical killing of this cover for use as an in situ mulch for establishment of persistent herbage of acceptable quality for pasturage or hay. Rye (Secale cereale L.) was drill‐seeded with fertilizer in September 1970 on spoil with pH 3.8 to 4.0. In May 1971, the rye was killed with a herbicide and then 3.6 metric tons of dolomitic limestone plus 56, 118, and 140 kg/ha of N, P, and K, respectively were broadcast as a blanket application. Selected forage legumes were surface seeded alone, and with a companion grass. Germination and seedling growth of the clovers and interseeded grasses were excellent. Over the 3‐year period, 1971–1973, herbage yields from red clovers averaged 3,000 kg/ha when established as a single species; with a companion grass, the combined yield increased to 4,400 kg/ha. Yields averaged 1,900 kg/ha for white clovers seeded alone, and 3,000 kg/ha with companion grasses. Highest yield in the third year was from crownvetch at 6,000 kg/ha. In the 0‐ to 7.6‐cm depth, pH ranged from 5.2 to 5.9 and in the 7.6‐ to 15.2‐cm depth, from 4.7 to 5.3. The results show that various forage legumes can be established on acid mine spoil and produce good ground cover and yields under this management system.