The N Factor: No More Crystal Ball

Although harvest and tillage are in full swing in many areas, preparation for the 2017 planting season is top-of-mind for many growers. Things like seed purchases, equipment plans, herbicide programs and fertility decisions are made well before the crop is dried.

The fertility decision is a critical process that requires intense scrutiny as many growers try to trim input costs to help make the budgets work. Decisions around nitrogen, phosphorus, and potassium are challenging because growers have to find the sweet spot between applying too much and too little. Recently an article in the Iowa State University Crop and Pest newsletter reviewed the decisions around P & K, which is a great resource for growers trying to make tough decisions around those two nutrients.

Equally important is the decision around nitrogen, which used to be as simple as
how much can I apply at the current price But factors such as environmental impact, changing uptake patterns of modern hybrids, and the emergence of new technologies that allow for more efficient timing and placement of nitrogen have made that decision much more complicated.

With the addition of these factors, growers no longer have to look into a crystal ball and guess what decision to make around nitrogen applications, especially growers applying fall nitrogen. Many are beginning to adopt a new approach called the ‘Base Plus’ approach to nitrogen applications. Instead of applying all of their N in the fall or at planting they are choosing to apply a base rate of nitrogen. By adopting this approach less N is exposed to loss from leaching or denitrification and growers are able to make more informed decisions about the crop conditions during the growing season at hand.

The past two years are prime examples of the benefit of a base plus approach. In 2015, excessive rains led to large losses of N. Growers who adopted a base plus approach reduced losses and saved on input costs. In 2016 large amounts of mineralized N were available to growers, so those who waited and measured were able to apply less N without sacrificing any yield.

Instead of looking into a crystal ball and making complete nitrogen decisions today about the 2017 growing season, utilizing a base plus approach can help you make more informed decisions which can not only save on input costs, but reduce losses into the environment.