Minnesota Crop News

Healthy soil (left) vs compacted soil (right) By: Bailey Tangen and Gabi Bolwerk, Extension educators Fall is a great time to start thinking about how to adjust your management practices to reduce erosion and improve soil health. A good first step is to understand the current state of your soil. To do this, you can perform a quick in-field soil health assessment. In this visual guide, we’ll walk you through how to conduct your own in-field soil health assessment. In an in-field soil health assessment, we look at the biological and physical properties of soil as they relate to soil function. This assessment can be done in 15-20 minutes and should be done in a few spots in your fields to get a full picture of how your soil functions. To learn more and to get help doing an assessment, call your local NRCS or SWCD office. These folks are willing to come out to your field, do an assessment, and provide management recommendations to protect the vitality of your operation and the producti...

Yucheng Wang, University of Minnesota, Entomology, Postdoc Researcher Tatum Dwyer, University of Minnesota, Entomology, Graduate student Fei Yang, University of Minnesota, Extension Entomologist Figure 1. Common stalk borer damage. Photo: Fei Yang, University of Minnesota During July-August 2025, we unexpectedly observed significant damage resembling European corn borer (ECB) injury along the edges of several corn fields in Martin and Mower Counties, Minnesota (Figure 1).  Figure 2. Common stalk borer in corn stalk. Photo: Fei Yang, University of Minnesota Affected plants showed rows of holes on the leaves and boring damage in the stalks. However, dissection of the corn stalk revealed that the culprit was common stalk borer (CSB), Papaipema nebris (Guenée) (Lepidoptera: Noctuidae), rather than ECB (Figure 2).  Figure 3.  Bt trait testing of the affected plants. Photo: Fei Yang,  University of Minnesota Bt trait testing of the affected plants confirmed the expr...

Photo: University of Minnesota Extension 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. Read the full transcript 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...

By Sally Raymond, Extension Educator and Program Manager, Pesticide Safety and Environmental Education Do you still need to recertify for your commercial/noncommercial pesticide applicator’s license this year? Check out these options from UMN Extension PSEE. Click here to register for an A/C/H workshop or go to PSEE’s webpage to see all options and workshop agendas. The following programs will get you recertification in categories A/C, A/H, or A/C/H: November 6 - The Park Event Center, Waite Park, MN November 14 - UMN Crookston Campus, Crookston, MN November 18 - Syngenta Seedcare Institute, Dennison/Stanton, MN** November 20 - The Bigwood Event Center, Fergus Falls, MN December 2 & 3 - Hilton Minneapolis, CPM Short Course & MCPR Trade Show , Minneapolis, MN **must be licensed in category H (seed treatment) to attend, A/H and A/C/H available If you have Category J (Rights of Way, Natural Areas, Forestry) on your license, need to recertify this year, and have attended or will...

Photo: University of Minnesota Extension By: Brad Carlson, Extension educator The University of Minnesota uses the Maximum Return to Nitrogen (MRTN) method for helping corn growers pick a nitrogen fertilizer rate. This method uses a database of results from many research trials around the state and then factors in the price of corn and the price of nitrogen fertilizer to find the most profitable nitrogen fertilizer rate for Minnesota corn growers. Understanding the “price ratio” is key. The price ratio is the price of nitrogen fertilizer per pound to the value of a bushel of corn.  For example, if N fertilizer costs $0.40 per lb. of N (or $656 per ton of anhydrous ammonia), and corn is valued at $4.00 per bushel, the ratio would be 0.40/4.00 = 0.10. Historically, the price ratio has hovered around 0.10 but in recent years high nitrogen fertilizer prices have resulted in higher price ratios. What is the price ratio looking like heading into 2026? The University of Minnesota’s corn f...

Photo credit: Isabella Portner By: Gabi Bolwerk, University of Minnesota Extension Educator, and Laura Paine, University of Wisconsin Extension Grazing Outreach Coordinator As farmers consider adopting soil health practices, it’s important to understand the implications for their operations. By exploring the impacts these management changes have on different aspects of their system, farmers can make the most informed decisions for their businesses and families. Cover crops and reduced tillage are some of the most widely adopted soil health practices. One management technique that often gets overlooked is crop and livestock integration. Crop and livestock integration is a management approach in which livestock are part of an annual cropping system. The cropland provides feed for the livestock, and the livestock provide nutrients to the cropland. Common crop and livestock integration practices include: Grazing cover crops Grazing crop residues Grazing annual or perennial forages Bale gr...

Landing page of Cove Crop Decision Tool Earlier this month, significant updates to the Midwest Cover Crops Council’s cover crop selector tool for Minnesota were published. A group of Minnesota researchers, agency staff, seed dealers, and farmers came together with Midwest Cover Crops Council staff to discuss and update Minnesota data in the cover crop selector tool. This revision reflects research and experience gained since the last update to Minnesota’s data in 2019. Some of the changes you will see in the tool include: Recommended seeding dates have been adjusted to reflect the most recent 30-year climate normal from the National Oceanic and Atmospheric Administration (NOAA). Seeding dates for each cover crop species are specific to each county based on climate data. Ratings for each cover crop species were reviewed. Potential advantages including quick growth and attractiveness to beneficial insects were reviewed alongside potential disadvantages such as risk of carrying disease t...

Photo: University of Minnesota Extension 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. Read the full transcript here 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? Click here to listen to all Advancing Nitrogen Smart podcast episodes. For the latest nutrient management informa...

Yucheng Wang, University of Minnesota, Entomology, Postdoc Researcher Dean Malvick, University of Minnesota, Extension Plant Pathologist Crystal Floyd, University of Minnesota, Plant Pathology Researcher   Fei Yang, University of Minnesota, Extension Entomologist Figure 1.Adult corn leafhopper in yellow sticky trap caught in Minnesota in 2025. Photo: Tatum Dwyer, University of Minnesota The corn leafhopper ( Dalbulus maidis ) has been detected again in Minnesota during the 2025 growing season. It was found in one corn field in Waseca County, where adults of the corn leafhopper were captured on yellow sticky traps placed on corn plants at the R5-R6 stage. We deployed yellow sticky traps from June through September, but adults were only captured in September. They can be found on both the adaxial (top) and abaxial (bottom) sides of corn leaves.  Adults generally have a light color, varying from yellow to white, with variable black spots on the abdomen. A key identifyin...

By Dean Malvick, University of Minnesota Red crown rot of soybean has been found for the first time in Minnesota. It was detected and confirmed in one field in southwestern Minnesota. This disease can cause significant yield loss in soybean depending on severity, weather, and timing of disease development. Red crown rot is caused by a soilborne fungal pathogen (Calonectria ilicicola) that infects the roots and lower parts of stems of soybean plants. Symptoms on leaves include yellow and brown patches between veins that are like symptoms of sudden death syndrome (SDS) and brown stem rot (BSR). Red coloration (similar to Rhizoctonia stem rot) and reddish dots develop on roots and lower stems, and roots are often rotted. The disease in Minnesota was confirmed to be red crown rot based on signs and symptoms of the disease as well as by isolation and identification of the pathogen via DNA sequencing. Red crown rot symptoms on roots and leaves of soybean ( Photos courtesy of N. Kleczewski, S...

Jamison Scholer, MDA Research Scientist. Reviewed by Jolene Warnke, Tana Haugen-Brown, and Sally Raymond, Extension Educators, UMN Pesticide Safety and Environmental Education program Sample of treated soybean. Photo credit: Tana Haugen-Brown Do you have leftover pesticide-treated seed and are not sure what to do with it? The Minnesota Pollution Control Agency (MPCA) has created a helpful fact sheet to guide you through proper disposal, along with relevant state regulations. You can find it here: https://www.pca.state.mn.us/sites/default/files/w-hw4-51.pdf . Although pesticide-treated seed isn’t categorized as a pesticide product, it is still considered industrial solid waste. Leftover pesticide-treated seed must be disposed of properly to minimize contamination of water resources and harm to wildlife. Planting treated seed on a farm. Photo: AdobeStock Farmers, retailers, distributors, and manufacturers who generate leftover pesticide-treated seed and its packaging are responsible for...

Fertilizer loading in Southern Minnesota co-op. Photo: University of Minnesota Extension By: Dan Kaiser, Extension nutrient management specialist For most farmers, the source of dry phosphorus (P) fertilizer is limited to what local retailers have on hand. The most common sources sold in Minnesota are mono-ammonium phosphate (MAP) and di-ammonium phosphate (DAP). Triple superphosphate (TSP) and Crystal Green (struvite) are also available in some areas. What are the differences between these sources and how should growers decide which one to use? What are the differences between MAP and DAP? The chemical formulas for MAP and DAP are: MAP: NH₄H₂PO₄ DAP: (NH 4 ) 2 HPO 4 Looking at the chemical formulas, the primary difference between MAP and DAP is the number of ammonia (NH₄) ions present. MAP contains one ammonium ion per phosphate versus two for DAP. An additional difference is that, when MAP is dissolved in water, it tends to produce an acidic pH while DAP is more alkaline (basic). Sin...

Claire LeCanne, Angie Peltier, Matthew Pfarr, Lizabeth Stahl, Extension educators - crops Photo: Sara Berg Market forces have resulted in lower farm-gate soybean prices through Chicago Board of Trade (CBOT) and local basis combinations. Soybean producers may wish to store soybeans if they feel they can capture higher prices later or if they simply have no acceptable market options in their geography. As soybeans are often sold right off the field it is helpful to review the principles for successful on-farm storage as some producers may wish to pivot. Soybean storage options Moisture is key but not the whole story for successful farm storage of soybeans. Soybean yield is typically normalized to 13% moisture and soybean buyers will pay full price for soybeans up to a moisture content of 13%. Also, grain bins will typically store 13% moisture soybeans for up to 6 months without spoilage at temperatures below 60°F.   However, even when soybeans are at the standard moisture cont...