Cutting versus herbicides: Tenth-year volume and release cost-effectiveness of sub-boreal conifer plantations

Abstract

Few cost-effectiveness studies of vegetation management in conifer plantations are reported in the literature. This study provides follow-up cost-effectiveness analysis from research conducted at the Fallingsnow Ecosystem Project in northwestern Ontario, Canada with the objective of determining the relationship between release treatment costs and planted white spruce (Picea glauca [Moench] Voss) stem volume ($ m-3) ten years after alternative release treatments. Treatment cost estimates for 2003 were calculated by applying 1993 time-study data to estimated 2003 market costs for each treatment component. Untreated control plots had no treatment costs and were not included in the analysis. Including them will always suggest that doing nothing will be the most cost-effective, regardless how limited spruce volume is. The most cost-effective treatment was the aerial application of herbicide Vision ($12.16 m-3), followed by the aerial application of herbicide Release ($12.18 m-3), cutting with brushsaw ($38.38 m-3) and mechanical tending by Silvana Selective ($42.65 m-3). No cost differences were found between the herbicide treatments (p = 0.998) or between the cutting treatments (p = 0.559). The herbicide treatments were three-fold more cost-effective than the cutting treatments (p = 0.001). This analysis only considered the planted conifer component of these young stands. Key words: clearing saws, competition, forest vegetation management, glyphosate, Great Lakes – St. Lawrence Forest, herbicide alternatives, mixedwood, pesticide, release treatment, triclopyr, weed