Minnesota Crop News

Join us Wednesday, July 22nd  for the weekly summer Field Notes webinar when we welcome Fei Yang , Extension Corn Entomologist, and Brett Arenz , Director of the University of Minnesota Plant Disease Clinic. If you aren't registered for these free webinars, visit: z.umn.edu/FN2026. Corn insects and disease identification will be the focus of the July 22, 2026 session of Field Notes. What is Field Notes? Crop producers and agricultural professionals face a host of challenges, including pest issues, agronomic concerns, and soil fertility questions. The U of MN Extension Strategic Farming program addresses your crop-related concerns through information-packed, research-based, informal discussions with specialists in the field. You can also ask questions directly to Extension faculty and staff during this program. Strategic Farming: Field Notes features live weekly online interactive discussions on cropping issues as they arise throughout the growing season.  The 2026 season will ...

Small grains harvest is underway in Minnesota.  Initial reports from southern Minnesota indicate better-than-expected grain yields with good quality.  One challenge oat growers face is green stems, even when the grain is more than dry enough to start harvest.  Margaret Smith, Albert Lea Seed agronomist, wrote a blog post for their growers explaining why this happens and how to manage it as best as possible. I encourage you to read the post . Now is also the time to check the incidence and severity of Fusarium Head Blight (FHB) in spring wheat across the Red River Valley.  The ideal time to get the best estimate is three weeks after you made the heading application.  Given the dry, hot weather the spring wheat crop endured the past two weeks, this optimum time is probably a bit earlier. Check fields that were seeded to varieties rated susceptible or very susceptible (a rating of 6 or worse in the Minnesota variety trials ) on old corn ground first, even if...

By: Ryan Miller, University of Minnesota Extension Educator - Crops, Jeff Coulter, University of Minnesota Extension Corn Agronomist, Brad Carlson, University of Minnesota Extension Educator - Nutrient Management and Water Quality, and Dean Malvick, University of Minnesota Extension Pathologist - Field Crops Environmental stresses The “heat dome”, hot temperatures during the early reproductive stages of corn development, what does it mean for Minnesota’s corn crop? The Minnesota corn crop is about a week ahead of normal and currently has adequate moisture but limited precipitation or chances for precipitation means things are drying out. Fortunately, the temperature conditions are expected to be cooler this coming week. So how is the heat affecting corn that is pollinating or starting to pollinate? Current high temperatures have been in the low 90’s, and corn can tolerate those temperatures without issue. Things have been drying out with the lack of precipitation and during hot dry ...

The blast furnace that was the weather for the past few days, the variability in precipitation received in the preceding week or weeks, and the immediate forecast all point to shorter leaf wetness durations.  This, in turn, means less risk of FHB infections for the remaining spring wheat acres that have not reached anthesis yet. Meanwhile, Bacterial Leaf Streak (BLS) is thriving in these windy, humid conditions and can be found across the region. Leaf rust has been found at extremely low levels in a few spots in the Red River Valley, while a few FHB infections were found in the winter wheat variety trials on the Northwest Research & Outreach Center.  It will be a difficult decision whether to spray a fungicide to suppress FHB if drought stress becomes more evident in your fields with each passing day.    Therefore, the advice this week is as follows: Spring Wheat -  Apply a fungicide at Feekes 10.51 (beginning of anthesis) if you find either tan spot, Septor...

The FHB risk models responded as expected, and the risk for FHB infections, depending on the variety's susceptibility to FHB,  increased from low to moderate risk towards moderate to high risk. This week's dew points are forecasted to remain high for a couple more days across much of the state. That means hot and muggy conditions during the day, and higher nighttime temperatures at night.  Consequently, the risk of FHB infections will remain moderate to high depending on the variety's FHB rating.   Note that the national model indicates a high risk for a greater percentage of the state when compared to the NDSU FHB risk model output for individual  NDAWN/MAWN stations.  This is an artifact of the weather data used in each model.  The NDAWN/MAWN stations used the weather data collected at that station, while the national model uses interpolations of weather data collected from National Weather Service (NWS) weather stations and the NWS weather forecast ...

This week's update is NOT a carbon copy of last week; while the fields still are all but void of disease and pests of any kind, the immediate weather forecast is not. Extreme heat is forecasted for the southern half of the state. Luckily, the grainfill period is well underway for the spring cereals and near completion for the winter cereals.  The risk of yield losses caused by fungal diseases is very limited at this stage of the game. Fusarium head blight infections can still occur and, consequently, deoxynivalenol (DON) can still accumulate in the grain.  However, the FHB risk models indicate low risk across the southern half of the state. In the northern part of the state, the situation is not the same.  In the southern half of the Red River Valley, about half the spring wheat crop just reached anthesis this past week.  Spring wheat in the northern half of the Red River Valley will start to reach anthesis this week.   And while daytime highs are not pred...

This is the first small grains disease & pest update of the 2026 growing season.  The scouts are receiving their training this week and will start their weekly routes next week.  Meanwhile, warmer-than-average daytime high temperatures are pushing crop development, and the earliest-seeded spring wheat, spring barley, and oats are already at the heading stage across the southern third of the state.  That means it's time to make fungicide decisions to suppress Fusarium Head Blight (FHB) and control any other fungal diseases that may be present.  Leaf wetness duration is key to allowing fungal infections to take hold.   The latest US Drought Monitor , issued yesterday,  has much of Minnesota classified as abnormally dry or in a moderate drought.  While the drought monitor does not tell whether dews stay around long enough to reach the minimum leaf wetness durations, the current map is somewhat informative if you overlay the NDSU Small Grain Disea...

While an ornithologist might say spring starts when the sandhill cranes have returned from their wintering grounds in the southern US and northern Mexico, a cereal pathologist may look for aecia of Puccinia cornonata on buckthorn to tell that spring is underway.  The picture below is from Steele County in SE Minnesota and confirms that the crown rust season of oats has started. That means that two of the three corners of the disease triangle are now in place.  Favorable conditions for the spores released by these aecia will be the third and final corner of the disease triangle for crown rust to start in oats. This past week, however, the risk models indicate that conditions have been too dry and that the resulting dew periods have been too short for crown rust to successfully infect oats at this point.   To use the risk model, simply select the MAWN/NDAWN weather station nearest to you, select the flag leaf growth stage, and look for the number of consecutive days ...

The University of Minnesota Extension will hold six hands-on small grain clinics and plot tours in the coming weeks. The aim of the clinics is to get you ready to tackle any disease and pest problems should they develop between now and the all-important flowering time in wheat, barley, and oats. These clinics will be held at the on-farm small grain trials near Rochester, LeCenter, Fergus Falls, Oklee, Humboldt, and Strathcona.   The date, times, and location details are as follows: Rochester - Wednesday, June 10th from 10:00-noon at the Lawler Research Farm northwest of the intersection of Collegeview Road NE and 70th Ave NE (Google Plus code - 2MF6+972 Chester, MN) LeCenter - Wednesday, June 17th from 10:00-noon at the Ruth Hoefs and Ron Pomije  Farm east of the intersection of  211th Ave and 340th Street (Google Plus code - F84C+X68 Lexington, Minnesota) Fergus Falls - Monday, June 22nd from 10:00-noon at the Walkup Farm southeast of the intersection of Co Rd 26 ...

Anthony Hanson, Extension Educator - Field Crops Integrated Pest Management (hans4022@umn.edu), Angie Peltier, Extension Educator - Field Crops, &  Jochum Wiersma, Extension small grains specialist.  Since 2011, University Minnesota Extension has conducted a small grains insect and disease field survey in western Minnesota as part of a collaboration with North Dakota State University. This effort has been funded by the Minnesota Wheat Research and Promotion Council through wheat check-off dollars to inform producers and the research community of the presence of disease and pests (Fig. 1). This effort relies on  field locations volunteered by Minnesota wheat farmers .   Figure 1. Severe and widespread true armyworm infestations were found by scouts during late Julyin 2025 that resulted in yield loss due to defoliation or head clipping just prior to harvest. Photo: Jordan Hunnicutt, 2025 IPM scout. Through this program, UMN Extension gives individual alerts...