Ten-year response of northern hardwood stands to commercial selection cutting in southern Quebec, Canada

Trees sampled from 12 uneven-aged sugar maple (Acer saccharum, Marsh.) dominated stands in southern Quebec were measured 10 years after commercial single-tree selection cutting. Dendrochronological analysis revealed that growth response to treatment was immediate for all three species. Species-specific response was, however, stronger for American beech (Fagus grandifolia, Ehrh.) than for sugar maple and yellow birch (Betula alleghaniensis, Britton). When averaged for 5-year periods, species growth during the second 5-year period after treatment remained significantly higher than their growth prior to treatment. Computations of whole stand minimum and maximum mortality (0.04 and 0.20 m2 ha−1 year−1) and the associated net growth (0.21 and 0.37m2 ha−1 year−1) were in the range of what was observed in the Quebec Government experimental blocks. Finally, at lower basal areas (i.e. after cutting), the growth of the survivors was correlated with variations in stand basal areas, while it was not the case at higher basal areas (i.e. prior to cutting). This suggests a significant enhancement of the survivor growth in these deciduous forests may only happen with a post-harvest basal area of 18 m2 ha−1 or less. Recommendations with respect to residual basal area and timber improvement rules are proposed which also take into consideration conclusions found in a literature review.