N Rate App

Wisconsin’s Corn N Rate Calculator

LINK TO THE APP STORE FOR IPHONE AND IPAD

LINK TO THE APP STORE FOR ANDROID

The Corn N Rate app calculates a nitrogen fertilizer rate for your field using University of Wisconsin recommendations designed to assist Wisconsin producers in selecting an N rate that improves profitability when N and corn prices fluctuate. Maximum return to N (MRTN) is the N rate that will be most profitable for a particular N:Corn ratio. The MRTN rate is the LARGE number expressed in lbs N/acre (total to apply) including N in starter. Below that number is the range of N rates that result in profitability within $1/acre of the MRTN rate.

How to use the free MRTN calculator app:

  • Tap the white boxes to begin entering the dollars per ton of fertilizer, the percentage on nitrogen in the fertilizer and the dollars per bushel of corn expected. How to enter the numbers — All numbers are entered as whole
    numbers. This app will add the decimal point automatically for the Corn Price. To enter $5.00 for corn, simply type 500 or just 5. If you want to enter $10.00, simply type 1000 or 10. There is a special way to enter a price below $1.99; you simply type a “0” first, then the price. To enter $1.50, you type 0150.
  • Tap a button to choose your soil yield potential or soil type. And tap a button for previous crop or irrigation.
  • Your fields MRTN rate will be displyed in lds N/acre (total to apply), as well as the MRTN rate range.
  • Look at  the “N Credits” and “Guidelines” screens for important adjustments to the MRTN rate.
  • E-mail your report to save or share your Wisconsin Corn N Rate information.
  • To determine soil yield potential, consult UWEX publication A2809 or contact your county agent or agronomist.