Evaluation of Low Spoil Compaction Techniques for Hardwood Forest Establishment on an Eastern Kentucky Surface Mine

Abstract

Abstract. To return surface mined areas in eastern Kentucky to productive forests, the compaction of mine spoil must be minimized or ameliorated. Four methods to reduce compaction on reclaimed surface mines were compared at the Bent Mountain research site in Pike County, Kentucky. The methods included: single shank ripped spoil, triple shank ripped spoil, excavated spoil, and rough graded spoil. Normally graded spoil was also examined as a control to represent a traditional reclamation practice. A single shank ripper was used in gently sloping areas to a depth of ≈ 2-m, while the triple shank ripper was used primarily on level spoil to a depth of ≈ 1.5-m. Both rippers were pulled with a D-11 dozer. Excavated spoil was created by digging out compacted spoil to a depth of ≈ 1-m and dropping it in place. The end dump or rough graded spoil was created by dumping mixed sandstones and shale spoil from a dump truck to a depth of 2 to 2.5-m followed by minimal grading (single pass) with a D-9 dozer to strike-off the piles. All sites were planted with native hardwood species in 2004. Three plots measuring 50 x 50-m were established within each spoil treatment. All trees within the research plots were tagged and have been examined each year for survival and growth characteristics. Bulk density was also measured annually using a nuclear density probe. Preliminary results show several statistically significant differences in tree height and survival. Survival for white oak (Quercus alba) was significantly higher for all reclamation methods compared to the control, and end dump was significantly higher than excavated. Green Ash (Fraxinus pennsylvanica) height was significantly greater for all reclamation methods compared to the control, and single shank ripped was significantly higher than all methods. For black locust (Robinia pseudoacacia) height and northern red oak (Quercus rubra) survival all methods except excavated were significantly greater than the control.

Evaluating Soil Genesis and Reforestation Success on a Surface Coal Mine in Appalachia

“…Survival of most tree species was high (70% or greater) and did not differ by spoil type after two growing seasons (Table 1), Similar findings for young seedlings planted in uncompacted spoil materials have been observed (Emerson et al,, 2009;Angel et al,, 2008;Casselman et al,, 2006;Michels et al,, 2007). Black locust and white ash exhibited 100% survival across all treatments and have repeatedly performed well in mine spoil environments (Emerson et al,, 2009;Skousen et al,, 2007;Angel et al" 2006;Ashby et al" 1985), Chestnut oak was the only species to show significant differences in survival by treatment, with the highest survival occurring in the brown sandstone (92%) followed by the gray sandstone (78%), mixed (54%), and shale (39%) treatments.…”

Hydrologic characteristics of Appalachian loose‐dumped spoil in the Cumberland Plateau of eastern Kentucky

“…Average spoil bulk densities did not differ between treatments, but did increase with depth. The measured spoil bulk density values were similar to those recorded by Conrad et al (2002) and Michels et al (2007) for other loose-dump spoil in eastern Kentucky with successfully established forests. As expected, no significant treatment differences were noted with regards to the physical characteristics such as drainage area, centre pipe slope, average longitudinal slope, and average side slope.…”

Establishing Pine Monocultures and Mixed Pine-Hardwood Stands on Reclaimed Surface Mined Land in Eastern Kentucky: Implications for Forest Resilience in a Changing Climate

“…Growth of loblolly pine dramatically outpaced growth of northern red oak in an adjacent site in legacy mined land in eastern Kentucky [49]. In that study, loblolly pine rapidly overgrew competing vegetation and shaded it out (in 4-8 yrs), leading to a bare understory characterized by a thick pine needle litter layer [13].…”