Buffer strips and trees between crops and waterways can filter nitrogen and prevent it from seeping into groundwater or rivers and streams. The Conservation Security Program (part of the U.S. Farm Bill), provides incentives to farmers for this practice.

Crops planted in the fall can capture nitrogen left over from the summer crop before it can be washed into the surrounding watershed by fall and winter rains or spring snowmelt. The next crop can use the captured nitrogen when the cover crop is killed prior to spring planting. Some grain crops such as winter wheat can also be planted in the fall.

New global positioning system (GPS) technologies allow farmers to vary the rate of fertilizer application across a given field precisely, tailoring the amount applied to a particular portion of a field to the amount needed by the plants growing there.

With conservation tillage, farmers grow crops with little or no plowing. Crops grown without tillage tend to lose fewer nitrates to the environment.

Biofuels developed with switchgrass and other perennial crops can provide a less-polluting source of energy than corn grain-ethanol. Perennial crops store nitrogen in their roots over winter and thus require less nitrogen fertilizer, and they can also capture soil nitrogen over a greater part of the year than can annual crops. Moreover, after initial planting they require no tillage. Plantations of small trees like willow and poplar provide another source of fuel more environmentally benign than growing corn.

Burning solid biofuels like switchgrass or small trees directly to create heat in buildings and factories provides an even more energy-efficient alternative to producing liquid ethanol. The energy gains from burning switchgrass are impressive—nine times more than by producing liquid corn-ethanol, with fewer environmental impacts. Sweden already heats a third of its homes and commercial businesses in this way, using biofuels grown on willow plantations.