Those farming practices are the ones that are economically and environmentally sound, and backed by good research.

"Growers need too look at the sources of nitrogen (N) they are putting down, and account for the nitrogen added [or removed] by the previous crop," said Gustafson.

"Also take into account the nitrogen supplied through the manure [in the case of livestock producers]. And consider anything applied commercially, through starter fertilizer, for example," he said.

As the season progresses, what's been figured out in the spring will determine what's needed throughout the season.

For growers in medium to fine-textured soils, the trend has been to put on all the N pre-plant. However, the trend has moved toward split applications - 50% pre-plant and the balance as side dressing when the corn is about 12 in. tall. Crops in sandy soils have been following that practice all along, due to greater potential for leaching, but more and more growers are finding benefit in the split application.

"Side dressing puts nitrogen down closer to the time when the crop needs it," said Gustafson.

Protecting N with good products, such as SuperU (see article above), and using split applications play an important part in managing the total N. "Basically," said Gustafson, "make sure you take credit for the N that is there, and then add the proper amounts."

These links from the University of Minnesota Extension Service, and from the University of Wisconsin offer good nitrogen articles, guidelines, and charts related to BMP and accounting for N levels. As always, talk to your Federated Agronomist for additional help with nitrogen management all season.