Credit for photo Steve Wilent Timber harvesting, prescribed burning, and other site preparation operations can reduce soil productivity by altering soil mineral particles, gasses, water, organic matter, soil organisms, and nutrients. Once degraded by excessive compaction, rutting, scarification, or erosion, soil productivity is difficult or impossible to restore. The best way to prevent reductions in productivity is to adopt forest management practices that minimize soil disturbance. Robert F. Powers, a science team leader with the USDA Forest Service's Pacific Southwest Research Station , is leading the National Long-Term Soil Productivity Study, a cooperative effort of the Forest Service , the Canadian Forest Service , and private timberland companies. The goals of the study are to unearth the effects of soil disturbance on productivity, develop soil-monitoring standards, and develop techniques for mitigating disturbance.
Powers says two key factors in soil productivity are porosity and organic matter.
Mechanical disturbance of soil reduces its porosity and can degrade productivity, depending on climate and soil type. Twelve Tips for Protecting Soils Minimize soil-disturbing activities on steep slopes and soils prone to erosion. Use low-impact machinery and operating techniques. Avoid repeated use of main skid trails. Lift logs off soil as much as is feasible.