Detrimental Soil Disturbance Associated with Timber Harvest Systems on National Forests in the Northern Region

摘要

Maintaining site productivity on forested lands within the National Forest System is a Federal mandate. To meet this mandate, soil conditions on timber harvest units within the Northern Region of the USDA Forest Service cannot exceed a threshold of 15% areal extent of detrimental soil disturbance (DSD; defined as a combination of compaction, puddling, rutting, burning, erosion, and displacement). The objectives of this study were to collate post-harvest soil monitoring data and to statistically document the areal extent of DSD resulting from timber harvest systems in the Northern Region. Current and legacy post-harvest soil monitoring data on National Forests throughout the Northern Region were collected to determine whether timber harvest systems (ground-based, skyline, or helicopter) used in the Northern Region result in DSD levels in excess of the mandated 15% areal extent. Statistical models developed in this study showed significant differences in the areal extent of DSD following timber harvest operations among ground-based, skyline, and helicopter harvest systems; among harvest seasons; and among National Forests.