In the past decade, scientists have been reporting that America’s move from burning coal to natural gas and low-sulfur coal has led to a large decrease in the amount of atmospheric sulfur, compared to 40 years ago. And while that’s good news for the environment, it also has led to a new challenge for the country’s farmers.

University studies indicate you could save as much as $52 per acre by delaying applications of phosphorus, potassium or sulfur if soil tests are above critical levels.