Selection cutting in over-mature spruce–fir stands in Quebec

Abstract

On the North Shore of the St. Lawrence River in the boreal forest (Forest Section B.1b) there are extensive stands of old-growth black spruce (Piceamariana (Mill.) B.S.P.) and balsam fir (Abiesbalsamea (L.) Mill.). They grow on high-quality valley-bottom sites with a diameter class distribution that is close to the theoretical ideal of the straight-line log relationship considered ideal for selection forests.In 1962, two stands containing about 3500 ft3/acre (246 m3/ha) on 36 acres (14.5 ha) were cut to remove between 20% and 50% of the volume in the form of a selection cut. Basal area and volume, growth, ingrowth, mortality, logging damage, and blowdown losses were monitored in two 5-year remeasurements on a network of 72 permanent sample plots. Only 18 of these plots showed a net loss in basal area for the 10-year period after treatment.It is concluded that in sheltered locations it could be possible to maintain stands such as these in a productive and aesthetically pleasing condition by careful selection cutting.