Examination of Potential Highgrading for Selective Helicopter Logging in the Queen Charlotte Islands

Abstract

It has been suggested that highgrading of preferred species and grades may be occurring in forest stands as a result of single-stem helicopter logging operations on the Queen Charlotte Islands. The possible occurrence of highgrading is a very contentious issue in the area. Despite this, no comprehensive analyses of this issue has yet been performed due to a lack of available post-harvest summary data at the cutblock level. The primary purpose of this study was thus to determine if evidence for highgrading exists based on a comparison of cruise and scale data for grades and species distributions on the west coast of Graham Island. A secondary purpose was to determine if greater volumes are being removed than prescribed in the heli-select system. Conventional clearcut blocks were used as a control group to account for discrepancies between cruise and scale data. Data for grades and species distributions were compared graphically, as well as statistically using Mann-Whitney tests. The analyses revealed that there is a particular focus on harvesting the highest grade categories and consequently, a lesser removal of the lowest grade categories. There is also a statistically greater removal of sitka spruce, and a similar trend is apparent for western red cedar. It can thus be concluded that highgrading is occurring in the heli-select harvest stands in the area, although further analysis would be required to determine the corresponding magnitude as well as the factors that may be influencing it.

Description

Keywords

Citation

DOI

ISSN

Creative Commons

Creative Commons URI

Items in TSpace are protected by copyright, with all rights reserved, unless otherwise indicated.