Minnesota Crop News

Sachin Dhanda, Former weed science postdoctoral researcher, Sithin Mathew,  Weed science graduate student, and Debalin Sarangi, Extension weed scientist Corn field planted in mid-May requires  postemergence herbicides for weed control. Photo: Debalin Sarangi Herbicide labels typically specify growth stage or crop height cutoffs (whichever comes first) for herbicide application, and the preharvest intervals (PHI) indicate the minimum time required between the last herbicide application and crop harvest. The restrictions are crucial to prevent potential crop injury, herbicide carryover, environmental or food safety issues, and other potential concerns. When tank mixing herbicides, the most restrictive label determines the cutoff. Always consult herbicide labels before application to ensure compliance. Below is an updated table (as of June 17, 2025) summarizing field corn growth stage or height cutoffs and PHI for commonly used postemergence herbicides. The growth ...

Diseases Last week, the scouts continued to find a few fields with tanspot at low incidence and severity.  Since last Thursday, widespread rains across much of Minnesota have allowed for much longer leaf wetness periods. Only the Red River Valley north of Hwy 200 continues to miss out on any measurable amounts of rain.  Consequently, the conditions for small grain diseases, including FHB, to develop are much more favorable for most. This means that, compared to a week ago, the disease management/fungicide recommendations are changing. For oats and barley that will be reaching Feekes 10.5 (or fully headed), switch to a fungicide labeled for the suppression of FHB, as the risk forecast for the remainder of the week remains moderate to high across all but the NW and SW corners of the state. Likewise, apply a fungicide labeled for the suppression of FHB in wheat when the crop reaches Feekes 10.51 (or beginning of anthesis). Choose one of the premium fungicide products when your ...

By Neal Kittelson, MDA, reviewed by Tana Haugen-Brown, UMN Pesticide Safety and Environmental Education Extension educator, Sally Raymond, UMN Pesticide Safety and Environmental Education Extension educator, and Jolene Warnke, UMN Pesticide Safety and Environmental Education Extension educator You may have noticed lately more references to the Endangered Species Act and pesticide labels. Why now? The Environmental Protection Agency (EPA) has developed new “strategies” for how they are handling its obligations under the Endangered Species Act (ESA). The EPA released the finalized Herbicide Strategy on August 20, 2024, and the Insecticide Strategy on April 29, 2025. The finalization of these strategies will result in several changes to pesticide labels that users will need to be aware of before making applications. Updates to pesticide labels are being implemented through the pesticide registration process and will take considerable time to fully implement, so be sure to fully read y...

By: Tarah Young, Extension educator, Dan Kaiser, Extension nutrient management specialist, & Jochum Wiersma, Extension small grains specialist Hybrid winter rye is gaining popularity in Minnesota for its strong yield potential and adaptability. A multi-year study across Minnesota shows that hybrid winter rye can achieve high grain yields with significantly less nitrogen than previously recommended—especially when most of it is applied in the spring. Strategic nitrogen management not only boosts yield but can also reduce lodging and nitrogen loss risks. Background Hybrid winter rye is gaining traction in Minnesota thanks to its hardiness and potential for high grain yields. This winter cereal offers many advantages over traditional open-pollinated varieties. These hybrids produce: Higher yields (25–40% more than open-pollinated rye) More tillers per plant (2 to 4 times more) Lower risk of ergot due to improved pollination Shorter, sturdier plants that resist lodging better These tra...

Dr. Rob Proulx at North Dakota State University updated the recommendations for ground application of fungicides to combat Fusarium Head Blight.  The extension bulletin detailing the new recommendations can be found here .  The long and the short of the updated recommendations is to use TeeJet's new asymmetric dual spray nozzles (Photo 1). These nozzles were specifically designed to spray fungicides at anthesis in cereals.  This new style allows for ground speeds between 10 to 15 mph without sacrificing control when using a spray volume between 10 and 20 gallons per acre and pressure yielding a coarse droplet size.  For example, a sprayer equipped with AI3070-03VP nozzles will deliver a coarse droplet size at 60 to 80 psi to between 11 and 12.5 gpa at 10 mph.  When equipped with AI3037-04Vp nozzles, that same sprayer can travel up to 15 mph at 70 psi to deliver 10 gpa. Photo 1 - TeeJet  AI3070-03VP nozzle (Photo credit: TeeJet Technologies)

Jamison Scholer, MDA Research Scientist, Jolene Warnke, UMN Pesticide Safety and Environmental Education Extension educator, and Tana Haugen-Brown, UMN Pesticide Safety and Environmental Education Extension educator Responding to pest threats that emerge in your crop fields and supporting beneficial insects (predators and pollinators) living around your farm doesn’t need to be mutually exclusive. Thoughtful consideration of pesticide selection, use timing, and application method can give you the benefits of both. Supporting beneficial insects that call your lands home means more tools in your arsenal to maximize yields and minimize pesticide inputs when economic thresholds are followed. For example, in soybean, pollinator visitation can increase yield in many nectar producing varieties 1, 2 . Maintaining untreated, uncultivated land around crop fields, such as field margins, ditches, conservation strips, etc., help support pollinators and predators that feed on crop pests and may reduc...