Just a year ago, we were looking at all-time high prices for many different kinds of fertilizer including Nitrogen (N). At that time, prices were going up mainly fueled by the skyrocketing price of oil. Anhydrous Ammonia (AA) which is a major source of nitrogen for growing corn in our area requires petroleum products in its manufacturing process. Since corn is a grass, it requires additional nitrogen in order to produce a grain crop at a profitable level. Traditionally, a dollars worth of nitrogen fertilizer returned at a ratio of 7 or 8 per dollar invested. AA had been priced around $400 per ton. Since AA is 82% nitrogen that works out to 1,640 pounds of nitrogen per ton or about $.24 per pound of actual N. With the big drive-up of oil prices (up to $147 a barrel at its peak) AA prices correspondingly took a big hike also. By last summer, suppliers were telling farmers that they had to lock in now in order to assure that they would have access to AA for fall application for the 2009 corn crop. Many farmers were forced to commit to Anhydrous Ammonia prices at $800 to $900 per ton or double what they were at just a few months before. Then the prices climbed again until we were at $1,150 to $1,200 per ton or about $.75 per pound of actual N by last October. This tripling of prices also brought along huge price increases in almost all other crop inputs. Seed corn jumped to around $100 per acre, up from $55 to$60 just a few years earlier. Fortunately, corn and soybean prices were strong and we could support some increases in inputs. And of course, we did see land rents increase substantially, currently at around $165 per acre for 2009 production.
So where are we at right now? Well, crop input prices have come down somewhat and have stabilized for now. Anhydrous Ammonia is currently at around $750 to $850 per ton or around $.50 for a pound of actual N. With the high prices in place, it is essential that N fertilizer be applied in such a way that the potential for loss be kept at a minimum. Best management practices that will achieve this goal have been identified and are now in print or available electronically. Printed copies are available at no cost from you local extension office. They are also available online. There are 5 publications and each has a different web address. These are as follows:
1.Best Management Practices for Nitrogen Use in Minnesota www.extension.umn.edu/distribution/cropsystems/DC8560.pdf
2.Best Management Practices for Nitrogen Use on Coarse Textured Soils. www.extension.umn.edu/distribution/cropsystems/DC8556.pdf
3.Best Management Practices for Nitrogen Use in South-Central Minnesota www.extension.umn.edu/cropsystems/DC8554.pdf
4.Best Management Practices for Nitrogen Use in Southeastern Minnesota www.extension.umn.edu/distribution/cropsystems/DC8557.pdf
5.Best Management Practices for Nitrogen Use in Southwestern and West-central Minnesota. www.extension.umn.edu/cropsystems/cropsystems/DC8558.pdf
Another important point, nitrogen is nitrogen, regardless of the source. There are a lot of people selling various fertilizer products that make statements about different sources of nitrogen. Research has shown that, if applied properly so that loss was minimized, all sources of fertilizer N had an equal effect on yield if the same rate of N was applied in all cases. In other words, "a pound of N is a pound of N". With today's higher commodity and fertilizer prices the debate about sources of fertilizer N are starting all over again. There is no difference in the application method of nitrogen fertilizer. It is important to remember that the overwhelming amount of N used by the corn plant must enter through the roots. Very small percentages are taken up through the leaves. A higher priced fertilizer product does not mean that it is a better product.