Loblolly pine site index on reclaimed mineland in East Texas

Abstract

Federal surface mining regulations require that land disturbed by surface mining be restored to a productive state capable of supporting preexisting land uses. Loblolly pine (Pinus taeda L.) plantations are a widespread reclamation land use in East Texas; however, the productivity of these plantations compared with that of those on unmined lands is not well documented. We quantified the current site qualities of loblolly pine plantations on two mines (Beckville Mine and Oak Hill Mine), which differ in the method of overburden replacement. Substituting mixed overburden for topsoil (done at the Beckville Mine) generally results in no distinction of original soil layers after reclamation, whereas removing and mixing the premining upper, oxidized soil layers for topsoil in the postmining reclamation areas (done at the Oak Hill Mine) creates some stratification. Nonlinear modeling of stem analysis data indicated that the current site indices are 61.1 and 61.9 ft at 25 years for the Beckville Mine and Oak Hill Mine, respectively. The current site indices (postmining) for each mine did not differ statistically from approximated premining site indices nor was height statistically different between premining and postmining at any age. The two mine sites did not statistically differ. These results suggest that mineland reclamation on these mines has successfully restored premining levels of forest productivity.