A simple soil nitrate test can confirm this. Other on-farm sources could include irrigation water and legumes in the rotation. If manures or composts are used as soil amendments, they also contribute nitrogen. Creating biological diversity in farms and ranches can help reduce pest problems. Grass and legume covers do this by providing habitat for beneficials.
Diversified farms offer growers some protection from crop-specific freezes or droughts.
Philosophical shifts can help farmers make decisions that may save their farms' economic viability.