Reclamation of surface-mined forest land in the southern Appalachians

Most of the surface-mined land in the southern Appalachian coal fields of Virginia, southern West Virginia, and eastern Kentucky is forested before mining. For a variety of reasons, most surface-mined land will ultimately return to forest, either by design or through natural succession. The usefulness of forests on reclaimed surface-mined land for providing timber management opportunities depends on whether or not the land is reclaimed in a manner which creates a productive forest soil. Surveys of tree plantings on land that was mined prior to enactment of the 1977 Surface Mining Control and Reclamation Act (SMCRA) have shown that trees will grow well where 1) minesoils are non-toxic, 2) minesoils are deep, loose, and uncompacted, and 3) tree seedling establishment is not hindered by competition from an herbaceous ground cover. Several experiments were conducted to develop practical recommendations for post-SMCRA reclamation of surface-mined forest land to create these desirable minesoil conditions. An experiment designed to evaluate the effect of two contrasting spoil types revealed that the type of overburden material used as a topsoil substitute can have long-term effects on tree growth. After five years, average tree volume in a sandstone spoil was five times greater than tree volume in a siltstone spoil. In the southern Appalachians, oxidized (brown) sandstone is a good overburden to use as a topsoil substitute for forest land reclamation. A second experiment was conducted to evaluate the effect of surface grading practices on erosion, herbaceous ground cover, and tree survival and growth. After five years, study results revealed that traditional grading practices caused excessive soil compaction that resulted in higher erosion and poorer tree growth than treatments that left the soil in a loose condition. A third experiment was conducted to compare the effect of two herbaceous ground cover prescriptions (a tree-compatible ground cover versus the coal operator’s standard revegetation mix) on the establishment of white pine (Pinus strobus) and black locust (Robinia psuedoacacia) by direct seeding versus hand planting seedlings. After five years, on a minesoil derived from brown sandstone and rough-graded to reduce compaction, the tree-compatible ground cover produced more cover than the traditional ground cover, and the site index of the reclaimed land was estimated to exceed 30 m (100 ft). Based on results of this long term research program, recommendations for establishing a productive forest, capable of providing timber within a 30 year rotation are: 1) select an oxidized (brown) sandstone spoil for placement at the surface, 2) roughly grade the final surface to avoid compaction, 3) establish a tree compatible ground cover to protect the soil without overtopping trees, and 4) select an appropriate mixture of tree species and carefully plant trees by selecting good micro-sites for each seedling.