CONSERVATION TILLAGE AND TRAFFIC EFFECTS ON SOIL CONDITION

The soil condition resulting from a five-year cotton-wheat double crop ping experiment in a sandy loam Coastal Plain soil was investigated us ing intensive measurements of cone index and dry bulk density. Four ti llage treatments including a strip-till (no surface tillage with in-ro w subsoiling) conservation tillage practice were analyzed. The traffic was controlled in the experimental plots with the USDA-ARS Wide-Frame Tractive Vehicle. Besides the environmental benefits of maintaining t he surface residue, the strip-till treatment decreased cone index dire ctly beneath the row, decreased surface bulk density, increased surfac e moisture content, decreased energy usage, and increased yields. Cont rolled traffic was beneficial only when in-row subsoiling was not used as an annual tillage treatment. Although differences in soil conditio n were seen beneath the row middles where traffic occurred, this did n ot affect the soil condition directly beneath the row.