URBANA, Ill. — University of Illinois Extension and the Illinois Council on Best Management Practices (CBMP) have developed a new tool to help farmers and crop advisors to determine the optimum nitrogen rate for corn and to plan for split applications of nitrogen, a recommended best management practice.

The Maximum Return to Nitrogen (MRTN) calculator is a regional tool developed by Midwest land-grant universities to help growers calculate the maximum return they will receive from nitrogen applications to corn based on prices of nitrogen and corn derived directly from research data. The calculator is available at http://extension.agron.iastate.edu/soilfertility/nrate.aspx.

To promote the 4Rs of nutrient stewardship (right source, right rate, right time, right place), CBMP and Extension collaborated to take the MRTN calculator one step further, making it accessible via a smart phone app. The app allows a grower or certified crop advisor to take the recommended nitrogen rate for the region, choose from various sources of nitrogen (ammonia, 28 percent or dry), split the applications between fall, pre-plant, and post-applied, add in stabilizers, and calculate the corresponding application costs. A summary of the recommendation can be saved on the smart phone or tablet for future reference.

“Making the MRTN easily accessible and adding in the flexibility to account for split applications is critical to the ag industry’s goal of maximizing nutrient investment and reducing nutrient losses,” said Dan Schaefer, CBMP’s Director of Nutrient Stewardship.

“Partnering with U of I Extension ties in their expertise in promoting use of research and education to benefit agriculture and the environment,” he added.

The app is free on the Android or Apple systems, thanks to funding provided by CBMP through the “Keep it for the Crop by 2025” nutrient stewardship program. To access the application from Apple, go to http://itunes.apple.com/us/app/mrtn-nitrogen-application/id560788301?. To access the Android version, go to http://web.extension.illinois.edu/csrec/index.html, then click on the “Register” block in the upper right corner.

CBMP and U of I Extension encourage growers, certified crop advisors and fertilizer dealers to download the app when determining nitrogen needs for the 2013 corn crop and test its easy-to-use features.

For more information on the 4Rs and KIC 2025, go to www.KIC2025.org.