FarmTo understand the logistic challenges associated with feeding today’s high-yield crops, it may be helpful to imagine yourself as a Midwestern farmer in the United States preparing for spring planting season.

After testing your soil and conferring with your Certified Crop Advisor (CCA), you’ve contracted with your farm supply retailer to purchase and apply 100 pounds per acre (an acre is about the size of a football field) of diammonium-phosphate (DAP), a product containing 18 percent nitrogen and 46 percent phosphorus. Once this product arrives at the local farm supply facility, it will be blended with muriate of potash, or potassium (K), to be applied as a full diet for plants needing nitrogen (N), phosphorus (P) and potassium (K). You have 1,000 acres of corn, and consequently, you will need 100,000 pounds, or 50 tons of DAP. How does that DAP get from the place(s) of origin to your front gate?

The key materials used to make DAP are anhydrous ammonia and phosphoric acid. The anhydrous ammonia was shipped in from Trinidad on an ocean-going vessel. The phosphate rock was mined in Florida where it was treated with sulfuric acid to produce phosphoric acid. The phosphoric acid was subsequently reacted with the ammonia to make DAP, the product containing N and P that will be applied to the field.

The DAP was then loaded onto a flat-bottomed river barge, which was then shepherded with other barges across Lake Pontchartrain and up the Mississippi River by tugboat. Eventually, it made its way to a terminal in southern Illinois, where the DAP was offloaded to a bulk blending plant. There it was bagged and trucked along the interstate highway system to a retail crop protection and fertilizer outlet near your farm, from which you arranged purchase and application.

This example represents the challenge presented by serving one farmer at one location growing 1,000 acres of corn. When you consider that more than 80 million acres of corn are grown annually in the United States, and that corn is only one of dozens of crops including cotton, corn, wheat, hay, fruit, vegetables and flowers that must be fed, you begin to grasp the challenge of plant food manufacturing and distribution.