Canadian Forest Service Publications
Tree growth on and adjacent to contour skidroads in the subalpine zone, southeastern British Columbia. 1979. Smith, R.B.; Wass, E.F. Fisheries and Environment Canada, Canadian Forest Service, Pacific Forest Research Centre, Victoria, BC. Information Report BC-R-2. 26 p.
Year: 1979
Issued by: Pacific Forestry Centre
Catalog ID: 4081
Language: English
Series: Information Report (PFC - Victoria)
Availability: PDF (download)
Abstract
Natural regeneration of Engelmann spruce and subalpine fir in steep clearcuts (9 to 22 years old), established on, above and below contour skidroads, was examined in southeastern British Columbia. Height growth varied with position on skidroad, soil characteristics and aspect. It was generally slowest on the inner deeply gouged portion (cutbank and inner skidder track) of the skidroad and increased toward the outside (outer skidder track, berm and sidecast). On some clearcuts, growth on the outside portion of the skidroad was greater than in the logged but otherwise undisturbed portion. Tree growth was adversely affected on skidroads constructed in medium- to fine-textured soils (loam to silt loam) derived from alkaline parent materials. On these soils, reductions in site quality based on reduced height growth prorated over the whole clearcut were estimated as high as 15% for subalpine fir and 12% for Engelmann spruce. In contrast, disturbance on moderately coarse, acid soils on cool (north) aspects was judged to have beneficial effects on tree growth. In one such area, a prorated enhancement of subalpine fir and Engelmann spruce height growth of 22% and 18%, respectively, was estimated. The post-logging average annual height growth of advance regeneration exceeded that of post-logging regeneration growing on surfaces undisturbed by skidroad construction by 40 to 255%.
