Changes in soil nutrient status and seedling performance in response to harvest intensity on upland, shallow site types in Northwestern Ontario : 10th year results

Abstract

Although based on limited empirical data, concerns have been raised that increased nutrient removals associated with full-tree harvesting on shallow-soiled sites may result in reduced productivity in subsequent rotations. The objective of this study, therefore, was to compare and contrast the soil nutrient status and early stand development that resulted from a range of harvest intensities (i.e., a gradient of biomass and nutrient removals), including a full-tree harvest treatment, to determine if such treatments did result in reduced site productivity. The sites (3) selected for the study were mature, fire-origin, black spruce-dominated stands with well-drained, shallow-to-bedrock (<20 cm of mineral soil overtopped by a moderately thin Fibrimor humus layer), coarse loamy soils. Experimental harvests were conducted in 1995 that consisted of five, replicated (3) treatments: uncut (UC), tree-length (TL)--delimbed at the stump, full-tree chipping (FTC)--chipped debris was returned to the harvested plot, full-tree (FTH)--delimbed at roadside, whole-tree (WTH)--complete removal of vegetation and forest floor.