Revegetation of drastically disturbed lands, such as acid coal spoils, kaolin spoils, borrow pits, and severely eroded sites in the eastern United States, has been significantly improved by planting tree seedlings tailored in the nursery with the ectomycorrhizal fungus, Pisolithus tinctorius (Pt). On these disturbed sites, Pt promotes the assimilation and absorption of required nutrients, increases water absorption, reduces the absorption of toxic elements, and, apparently, reduces the overall

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... tress inherent on these sites. Repeatedly demonstrated benefits in forestation and mineland reclamation include significant increases in nursery seedling quality (reduced culls), survival, and growth in field plantings. Extensive research and field evaluations during the past 15 years have provided practical techniques for applying Pt in container and bare-root seedling nurseries. Types of commercial inoculum include vegetative mycelium, bulk spores, spore pellets, and spore-encapsulated seeds. A commer· cially available machine effectively and efficiently applies mycelial inoculum in bare-root nurseries. The demand for custom-grown, Pt-inoculated seedlings continues to increase. In 1990, 7 million seedlings were inoculated with Pt at 12 bare-root and container nurseries in the southern, central, and northeastern U.S. The Ohio Division of Reclamation planted approximately!).3 million Pt-inoculated pine and hardwood seedlings on 200 acres of abandoned minelands in southern Ohio during the 1990-91 tree planting season. Additional interest in the initiation of Pt seedling mineland reforestation programs has recently been expressed by state officials, private coal companies, and reclamation contractors in the central and southern U.S. Pt inoculation costs represent less than 5% of the total min eland reclamation forestation expense.