Force Requirements and Soil Disruption of Straight and Bentleg Subsoilers for Conservation Tillage Systems

摘要

Aboveground soil disruption prior to planting is not wanted in conservation tillage systems due to the need to keep plant residue in place. However, belowground disruption is necessary in many Southeastern U.S. soils to ameliorate soil compaction problems. To assist in choosing the best shank for strip-tillage systems which accomplish both objectives, comparisons were made between several shanks commonly used for conservation tillage systems to provide in-row subsoiling prior to planting. A three-dimensional dynamometer was used to measure draft, vertical, and side forces for experiments conducted in the soil bins of the USDA-ARS National Soil Dynamics Laboratory in Auburn, AL. A portable tillage profiler was used to measure both above- and belowground soil disruption. For use in conservation tillage systems, belowground soil disruption should be maximized while aboveground disruption should be minimized. Two parameters, spoil resistance index and trench specific resistance, were defined in the paper to consider the effect of draft force, aboveground soil disruption and belowground soil disruption. The two best shanks for conservation tillage systems based on these selection criteria are the BBP shank and the BWT shank, which are both bentleg shanks from different manufacturers.