The reclamation of acidic colliery spoil. IV. The effects of limestone particle size and depth of incorporation.
Abstract
The effects of different grades of limestone, up to 2.4 mm diam., and incorporation depths of 15 and 25 cm, on growth of Lolium perenne cv. S23 was investigated during 1976-8 in field experiments on colliery spoil. In a pot experiment the effect of 3 grades of limestone up to 3 mm diam. was investigated on L. perenne cv. S23, Trifolium repens cv. S184 and Lotus corniculatus. Deep incorporation of limestone improved plant growth over the summer but not in the winter; the growth advantage during the first season's growth was probably overcome by the disadvantage of limestone dilution at a greater depth. The coarser grades of limestone reacted more slowly than the fine grade and produced a long-term neutralizing effect.