Too Much of a Good Thing

Nitrogen is an essential element for crop growth. But nitrogen fertilizer is often applied at a much higher rate than what most crops need. Globally, about half of the nitrogen fertilizer applied to farm fields is not utilized by the crop and instead washes out into waterways or volatilizes into the atmosphere. This excess nitrogen harms human health, threatens biodiversity, and drives climate change. Nitrogen overuse also costs farmers more money because they apply more than what is needed. There is a growing consensus that nitrogen management needs to be improved and that overapplication must end.

The good news is that significant reductions in nitrogen use are achievable in the United States, and forward-looking policies can help reduce overapplication without diminishing crop yields or farm profitability.