With conservation tillage, farmers leave at least 30 percent of crop residue on the soil surface after their tillage and planting operations.
Doing so reduces soil erosion and runoff, increases water retention, and lowers agriculture's carbon footprint.
USDA's Economic Research Service (ERS) recently completed a 15-year analysis of farmer adoption of genetically engineered crops, and found that in 2006, about 86 percent of land planted with herbicide-tolerant (HT) soybeans was under conservation tillage. That's compared to just 36 percent of conventional soybean acres.
Also in 2006, 45 percent of all HT soybean acres were cultivated with no-till methods, as compared to just 5 percent of conventional acres.
ERS found a similar pattern for corn and cotton acres, though less pronounced.