Soil Bulk Density Recovery on Compacted Skid Trails in Central Idaho

In west‐central Idaho, the bulk densities of soil in major skid trails were compared with those of adjacent undisturbed soil in order to determine rates of recovery. Five study sites on each of two soils, one formed from granitic material (mixed, frigid, Typic Xeropsamments) and the other from volcanic material (fine‐loamy, mixed Dystric Cryochrepts), provided two chronosequences (five 5‐yr periods) of time since logging. Bulk density was measured at 5.1‐, 15.2‐, and 30.5‐cm depths. The percent increase in bulk density of soil on a skid trail over that on an adjacent undisturbed area was greater in the volcanic than the granitic soil, but recovery rates (slope of the regression line) for the two soils were not significantly different. Linear regression models showed a significant ( p < 0.05) recovery trend for all depths except the 15.2‐cm depth on the volcanic site. Except for the surface 5.1 cm of the granitic soil, none of the bulk densities in skid trails had returned to the undisturbed values in the 23 yr since logging.