Minnesota Fertilizer Trends-The Past 20 Years

By Bruce Montgomery, Minnesota Department of Agriculture

While penciling out some thoughts to share with Minnesota farmers, yet another e-mail came rambling across my computer reminding me of the turbulent fertilizer market -- with no immediate relief in sight. Not a bad justification to take a few moments to reflect back at our past fertilizer usage and determine what advancements, if any, have been made. As agriculture faces increasing environmental scrutiny, the more defensible information we can provide to the general public that agriculture is doing its share in protecting the environment, the better off we will be.The graph below summarizes the Minnesota statewide sales of nitrogen, phosphorus, and potassium across all crops since 1989. Considering some of the major changes over the past 20 years including accelerated ethanol production, CRP fluxes, and some recent record high commodity prices, Minnesota’s fertilizer sales have been surprisingly flat. While it does not appear to be much of a story line, there actually are some hidden successes to be unveiled.

From a statewide perspective, about 70% of the nitrogen fertilizer in the state goes into corn for grain production. Wheat accounts for another 16% with sugarbeets, potatoes and silage corn making up most of the balance.

Some interesting observations develop as the corn (grain) data is examined in the graphic below. First, the actual corn acres have steadily increased about 30% since the late 1980s. However production has catapulted over 80% over the same time period. Obviously the yield response (bu/A) also had to explode (not shown) for this type of production to occur. I may not be telling you anything new from your own observations from the topside view from the combine, but did you realize that Minnesota corn producers are doing all of this with basically the same fertilizer inputs used 20 years ago? Let’s recap the success of the corn farmer since the late 1980s: Corn acres (up 30%), corn yields (up 38%) and overall productions (up 85%) while nitrogen fertilizer use has risen only 12%. Additionally, it is likely that phosphate and potash use on corn has remained stable or even have decreased statewide over the past twenty years.

And there are probably similar success stories with other high-nutrient demanding crops like potatoes, wheat and beets.

There have also been some changes in the forms of fertilizer used over the past two decades. The most noteworthy are the changes in primary sources of nitrogen and phosphorus.

In the 1990s there was steady substitution of anhydrous ammonia for urea. Since the early 2000s, those two important N sources flip flop for the lead and together account for 75-80% of the nitrogen market. When switching over to more soluble nitrogen sources such as urea and 28%, please be sure to consider the proper timing and placement of these products. The University of Minnesota provides excellent guidelines specific for your area. See the following website for more information: www.mda.state.mn.us/protecting/bmps/nitrogenbmps.htm.

Getting the most out of your fertilizer inputs is a great message to share. It reflects a “win-win” scenario for both your pocketbook and our state’s environment.

With the turbulent fertilizer market, please take some time this winter to reexamine your fertilizer program. Many producers will be able to enjoy additional nitrogen reductions particularly through the proper crediting of past legume crops and manure applications. The state has a wealth of Certified Crop Advisors that can assist you. They can provide soil testing services and a lot of experience in managing nutrients. For more information on contacting one, please go to:www.certifiedcropadviser.org/find.