The long-term effects of silvicultural thinning and partial cutting on soil compaction in red pine (Pinus resinosa Ait.) and northern hardwood stands in the northern Great Lakes Region of the United States

Tarpey, R. A., Jurgensen, M. F., Palik, B. J. and Kolka, R. K. 2008. The long-term effects of silvicultural thinning and partial cutting on soil compaction in red pine (Pinus resinosa Ait.) and northern hardwood stands in the northern Great Lakes Region of the United States. Can. J. Soil Sci. 88: 849-857. Periodic silvicultural thinnings (23.0, 27.6, 32.1 m(2) ha(-1) residual basal area) in a red pine stand growing on a sandy soil in north-central Minnesota over a 57-yr period increased soil compaction as the intensity of the thinning treatment increased. Of the three different methods used to measure soil compaction (bulk density, penetration resistance, and saturated hydraulic conductivity), saturated hydraulic conductivity was the most sensitive, decreasing by 60% in the 23.0 m(2) ha(-1) basal area thinning treatment, as compared with the uncut control. Soil bulk density measurements were more variable, but generally increased with increased thinning intensity. Few differences in soil penetration resistance were found among the three thinning treatments. In contrast, no evidence of soil compaction was detected in a northern hardwoods stand growing on a rocky loam soil in north-central Wisconsin that had three thinning treatments (13.8, 17.2, 20.6 m(2) ha(-1) residual basal area), a two- stage shelterwood harvest, and a 20-cm-diameter limit cut over a 50-yr period. With the increased demand for forest products, fuel reduction operations in high Fire-risk stands, and biomass removal for energy production, more information is needed on the impact of multiple stand entries on soil compaction, and if compaction occurs, whether it will affect long-term soil productivity.