On today's episode of the Advancing Nitrogen Smart podcast, Brad and Dan talk about variable rate application - and zones in particular. What's the overall point to variable rate N application? How might an initial starting N rate be determined? How do farmers' fields and equipment introduce their own variables, and how can these variables be monitored? How should farmers think about - and plot out - field zones? What's the difference between a yield map and a zone map, and should farmers rely on yield maps for zoning purposes? Do the best yielding spots always need the most nitrogen? All of this and much more on today's show.

Guests:

• Brad Carlson, Extension educator (Mankato)
• Dan Kaiser, Extension nutrient management specialist (St. Paul)

Additional resources:

• With high nitrogen fertilizer prices and low corn prices, can you decrease your nitrogen rate for 2026?
• www.cornnratecalc.org (Corn Nitrogen Rate Calculator)
• Is variable rate nitrogen based on yield maps a good idea?
• Variable rate nitrogen: What are we trying to accomplish?
• Brad Carlson's email address: bcarlson@umn.edu
• Dan Kaiser's email address: dekaiser@umn.edu

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For the latest nutrient management information, subscribe to the Nutrient Management Podcast. And don't forget to subscribe to the Minnesota Crop News daily or weekly email newsletter, subscribe to our YouTube channel, like UMN Extension Nutrient Management on Facebook, follow us on X (formerly twitter), and visit our website.

If you have questions or comments, please email us at nutmgmt@umn.edu.

This month on the Nutrient Management Podcast, we talk about a recent increase in N rate recommendations for corn. Why have these suggested nitrogen rates for corn increased over time? How are regional differences across Minnesota factored into this increase? Why does the Maximum Return to Nitrogen (MRTN) method of N rate calculation bring economics into the mix? Why should growers focus on profit instead of yield? Won't a higher nitrogen rate make our SE Minnesota water issues worse? Our panelists answer these important questions - and many more - on today's show.

Guests:

• Jeff Vetsch, U of M researcher (Waseca)
• Daniel Kaiser, Extension nutrient management specialist (St. Paul)
• Brad Carlson, Extension educator (Mankato)

Additional Resources:

• www.cornnratecalc.org (N Rate Calculator)
• Updated corn nitrogen rates: What are we currently seeing for N fertilizer requirements in Minnesota?
• An introduction to MRTN: Efficiencies & economics in mind
• 2025 fall fertilizer outlook: Management tips during economic uncertainty
• With high nitrogen fertilizer prices and low corn prices, can you decrease your nitrogen rate for 2026?

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For the latest nutrient management information, subscribe to the Nutrient Management Podcast. And don't forget to subscribe to the Minnesota Crop News daily or weekly email newsletter, subscribe to our YouTube channel, like UMN Extension Nutrient Management on Facebook, follow us on X (formerly twitter), and visit our website.

If you have questions or comments, please email us at nutmgmt@umn.edu.

Support for the Nutrient Management Podcast is provided by Minnesota's fertilizer tonnage fee through the Agricultural Fertilizer Research & Education Council (AFREC). Learn more at MNsoilfertility.com.

Brad Carlson and Daniel Kaiser discuss the maximum return to nitrogen method (MRTN) for determining an optimal N rate on today's episode of Advancing Nitrogen Smart Podcast. What is the MRTN and why was it created? What are differences between an N investment model versus a maximum yield model? What should farmers keep in mind while using the MRTN? Where can Minnesota farmers, producers and ag professionals find the MRTN? All this and more on today's show.

Guests:

• Brad Carlson, Extension educator (Mankato)
• Dan Kaiser, Extension nutrient management specialist (St. Paul)

Additional resources:

• www.cornnratecalc.org (N rate calculator)
• Are you overspending on fertilizer?
• Nutrient Management
• Updated corn nitrogen rates: What are we currently seeing for N fertilizer requirements in Minnesota?

For the latest nutrient management information, subscribe to the Nutrient Management Podcast. And don't forget to subscribe to the Minnesota Crop News daily or weekly email newsletter, subscribe to our YouTube channel, like UMN Extension Nutrient Management on Facebook, follow us on X (formerly twitter), and visit our website.

If you have questions or comments, please email us at nutmgmt@umn.edu.

Advancing Nitrogen Smart is proud to be supported by the farm families of Minnesota and their corn check-off investment through Minnesota Corn.