Fertility Resources

Soil Sampling for Variable Rate Fertilizer

Soil Sampling for Precision Agriculture

"As various aspects of precision agriculture are implemented in Nebraska, some of the most frequent questions asked by producers, fertilizer dealers and crop consultants relate to soil sampling. Should I soil sample this field on a grid? What grid spacing should I use? How often should I sample? Can I use a yield map to tell where to soil sample? All of these are good questions, but often we do not have definitive answers. Site-specific management research conducted in recent years in Nebraska, however, provides some direction on how to implement a soil sampling program for precision agriculture."

In-Season Nitrogen Application

"Corn plants take up and use a large amount of nitrogen during the growing season. Making sure the plant has access to nitrogen as it approaches flowering can improve yields. In-season nitrogen applications help ensure the plant has adequate nitrogen to fuel kernel development.

Researchers are reporting the value of in-season nitrogen applications and suggesting growers can gain real economic and environmental benefits by adopting this practice."

"Corn takes up half its N supply between V8 and VT, a period that may comprise only 30 days. Providing adequate N for this period is a key goal of N management.
Spreading N applications is a good way to spread risks and reduce costs, but the extent to which this is practical depends largely on prevailing weather conditions.
Fall-applied N is at highest risk of loss. In all instances of fall application, only ammonium sources of N should be used, as well as a nitrification inhibitor such as N-Serve®.
Preplant N application may be considered in areas where growers are able to complete this practice without delaying planting beyond the optimum window."