Summary
As part of the American chestnut restoration project, Forest Service scientists have planted thousands of blight-resistant American chestnut seedlings on reclaimed abandoned mined lands in southeastern Ohio. While evaluating various planting protocols, they tested inoculation with several species of ectomycorrhizal fungi (which play a vital role in tree nutrition), including the well-known Pisolithus tinctorius. However, they found that a novel species of ectomycorrhizal fungus belonging to the genus Scleroderma was the most active and effective in the locations tested. This species appeared to be native to the reclaimed mined lands and was aggressive in forming beneficial symbiotic association with chestnut seedlings, even replacing the other species. Identification through DNA sequencing indicated that the novel species was closely related to Scleroderma areolatum and Scleroderma citrinum. This newly identified novel ectomycorrhizal fungus appears to be better suited to form functional mycorrhizae under environmental extremes. Large-scale tests of this fungus for the restoration of chestnut as well as in reforestation efforts on reclaimed mined sites are planned.