Influence of skid trails and haul roads on understory plant richness and composition in managed forest landscapes in Upper Michigan, USA

摘要

We evaluated impacts of disturbance in interior haul roads and skid trails on understory vegetation by documenting the areal extent of these features and plant composition along 10 m x 100 m belt transects. Ten belt transects were sampled in each of three comparable northern hardwood forests under even-aged management. These forests were approximately 80 years old and were last entered for thinning 4-6 years prior to sampling. Soil compaction, canopy cover, and the richness and composition of trees, shrubs, and herbs were quantified within each feature (i.e. haul roads, skid trails, and forest without soil disturbance) encountered along transects. These variables were also quantified in unmanaged northern hardwood stands of comparable age. Differences in photosynthetically active radiation (PAR) and soil moisture between haul roads and adjacent patches of forest were measured along line transects placed across haul roads, perpendicular to their main axis.