A recent study shows that the most heavily tile-drained areas of North America are also the largest contributing source of nitrate to the Gulf of Mexico, leading to seasonal hypoxia.

A new way to make topographic maps could help farmers use variable-rate fertilizer application to maximize returns, says James McKinion, a USDA scientist.

The increased use of no-till farming since the 1980s, and the increased use of glyphosate-resistant crops since 1996, has significantly turned farmers into environmentalists. Less soil has eroded, less chemicals have been applied, and less fuel has been used because of significant changes in farming practices.