Large tracts of land, officially described as 'reclaimed' from former mineral workings, are in poor condition. Problems include gullying, soil erosion, soil compaction, accelerated run-off and poor vegetation cover. Some of these problems are caused by low quality and inappropriate engineering. Some are due to poor land husbandry. There is a need for a national system of quality control inspection for land reclamation sites and provision for training in the special problems of managing reclaimed lands. However, many further problems result from natural soil-forming processes, notably the accelerated breakdown of newly exposed minestones. This chokes the soils with fine particles, decreasing permeability and increasing bulk density. Current research directed to correcting this problem uses trees to build new self-sustaining soils from the ground up and to promote the development of a large and active community of soil organisms. It is hoped that the polysaccharide secretions of these organisms will bind the newly created clays into stable soil aggregates.