Limited Impacts of Activated Carbon and Mycorrhizal Amendments for Pinus echinata Reforestation on Strip-Mined Soils

Strip mining creates widespread degraded landscapes that have low soil pH, high bulk density, impacted hydrologic processes, and an accumulation of heavy metals that limit revegetation efforts. To improve soil conditions and restoration success, soil amendments paired with native trees provide a potential solution. However, limited empirical studies have been conducted on the success of soil amendments to facilitate shortleaf pine (Pinus echinata Mill.) growth in the southeastern US. To fill this knowledge gap, a field trial was established on a reclaimed coal-mined site. Shortleaf pine seedlings were planted in a complete randomized block design with two soil amendment treatments: activated carbon and mycorrhizal inoculation, applied at a rate of 3.36 g/m2 and 42.5 g per tree, respectively. Soil treatment did not impact tree survival which concluded with a 69 ± 3% (mean ± standard error) survival rate. Activated carbon increased soil electrical conductivity (p = 0.037) and the mycorrhizal amendment led to increased soil Ca content (p = 0.004). After the first growing season, trees in the mycorrhizal-amended soil were 12% shorter (p = 0.016) than trees in the activated carbon treatment. While soil amendment resulted in minimal improvements to soil parameters, shortleaf pine was found to be an effective species choice for post-mined site reforestation.