Minnesota Crop News

Anthony Hanson, IPM Extension Educator; Bruce Potter, Extension IPM Specialist; Ken Ostlie & Bill Hutchison, Extension Entomologists; Angie Peltier & Ryan Miller, Extension Educators If you plan to have non-Bt corn fields in 2023, we are looking for potential European corn borer fall survey sites. To volunteer non-Bt fields for the 2023 fall survey, click here or contact Anthony Hanson at hans4022@umn.edu . The economics of corn production challenge farmers to minimize production costs. Hybrid selection is one way to reduce costs. Planting corn hybrids without Bacillus thuringiensis (Bt) proteins for protection against European corn borer (ECB) (Fig. 1), corn rootworm, or both will reduce seed costs. However, farmers could inadvertently reduce crop revenues by selecting hybrids without carefully considering hybrid yield potential or insect populations in their fields. Figure 1. European corn borer tunneling in corn stalk. Yield potential is the first thing to consider when se

By Angie Peltier, UMN Extension crops educator & Robert Koch, UMN Extension soybean entomology specialist On March 22, 2023, Robert Koch joined UMN Extension crops educator Anthony Hanson for a conversation about new and not-so-new soybean pests in Minnesota. This was an episode in the 2023 Strategic Farming: Let’s talk crops! series of webinars. To watch this episode: https://www.youtube.com/watch?v=srH9XWjpy9Q Insecticides labeled for managing soybean aphid Figure 1. Soybean aphid adult giving live birth to nymph. Photo: James Menger Soybean aphids (Figure 1) are by no means a new pest of Minnesota soybean; it has been more than 20 years since its arrival in the state. What is new about this pest is the shrinking list of insecticides that remain effective and labeled for use.  The US Environmental Protection Agency revoked the tolerances for the organophosphate insecticide chlorpyrifos (e.x. Lorsban, etc.). In 2022, it became no longer legal to use this active ingredient on cr

Photo credit: Melissa Wilson/UMN Extension By: Melissa Wilson, Extension manure management specialist; Yuzhi Li, Associate professor in alternative and organic swine production; and Curt Reese, Agronomy and soil scientist at the West Central Research and Outreach Center Key Points: As one part of a larger study, we’re growing hybrid rye using swine manure as the primary nutrient source In the first year of the study, the use of liquid swine manure tended to produce higher grain yields than solid or composted swine manure Application rates that supplied 60 to 120 pounds per acre of first year available nitrogen optimized yield without significantly overapplying phosphorus and potassium Hybrid rye grain and straw produced for the larger study will be tested as an alternative feed and bedding source for organic swine production What we did: Hybrid rye is being grown in Minnesota as an alternative to traditional winter rye varieties. In organic production systems, the grain may be used as

Photo: Jared Goplen Join us this Wednesday, March 29, for the final Strategic Farming webinar as Dr. Brian Luck, Associate Professor and Vice Chair of the University of Wisconsin Biological Systems Engineering Department, discusses planter adjustments that are important to consider before planters get rolling this April. Dr. Luck will review best management practices for maintenance and proper adjustment of downforce systems, row cleaners when operating in variable field conditions, closing wheels, and seed delivery tubes.  Many of these technology adjustments can aid in effective planting at higher speeds.  Following Dr. Luck’s presentation, Dr. Seth Naeve, University of Minnesota Extension soybean agronomist, will also be on the program to discuss early soybean planting trends and considerations. Bring your questions for the speakers, as there will be plenty of time for discussion. Seth will review new national resources for soybean growers developed by the Science for Success Agron

By: Dan Kaiser, Extension nutrient management specialist Plant tissue analysis is a singular tool that we have within our toolbox that can be used with other tools to try to help us assess nutrient deficiencies within fields. With studies funded by the Agricultural Fertilizer Research and Education Council (AFREC), we commonly use tissue analysis, not only as a way to assess performance of treatments within the field, but also as a way to collect data to look at evaluating currently used sufficiency guidelines for particular tissue analysis collected at diagnostic growth stages. There are a few things to consider when you're taking plant tissue samples. Sampling strategy First, timing of sampling is critical. We want to avoid sampling too early in the growing season or too late in the growing season. This is because too early in the growing season, plants typically have not taken up a large portion of their nutrients, and too late in the growing season, plants tend to redistribute

Craig Sheaffer, Extension forage agronomist, Nathan Drewitz, and Troy Salzer, Extension educators Heaving of alfalfa. Alfalfa can be killed if roots and crown are exposed to freezing temperatures or if plants are detached from the soil and cannot take-up water. In early January we discussed the beneficial effects of protective snow cover as a protective insulation layer for alfalfa plants over the winter. Surface, soil temperatures have remained near 32 F throughout the winter, a level that is not stressful for perennial plants. However, with melting snow in late winter and spring and saturation of the soil, forages are subject to the peril of heaving. Heaving mechanisms Heaving is a volumetric expansion of the soil caused by the segregation and expansion of frozen water (ice) in the soils. There are two forms: Primary heaving : This is caused by ice needles jacking up plants out of the soil during short duration, alternative freeze-thaw cycles in the spring. Secondary heaving : This

Phyllis Bongard, Extension content development and communications specialist Alfalfa field covered with 4 inches of snow. Photo: N. Drewitz This winter’s ample snow is good for alfalfa winter survival, but it can also favor insect pest survival. Drs. Craig Sheaffer, Extension forage agronomist, and Anthony Hanson, Extension IPM educator, had a wide-ranging discussion on the status of overwintering alfalfa and its pests in the March 15th Strategic Farming: Let’s talk crops session.  Outlook for overwintering alfalfa Overwintering alfalfa is typically most vulnerable during March and April when a thaw is followed by freezing temperatures. However, the significant blanket of snow (>4 inches) in much of the state is providing good protection as the alfalfa comes out of dormancy. The snow insulates the plants from soil and air temperature variations that are typical this time of year. As a result, Sheaffer expects little risk of alfalfa winter injury. However, water from snow-melt can p

Science for Success soybean specialists  The Science for Success partnership brings together 26 Extension specialists from land-grant  institutions across the country, representing more than 80% of US soybean acres. These specialists contribute their own state-gleaned knowledge and research results to the program to bring you sound, research-based Best Management Practices (BMPs).  A new webinar series,  Keys to Early Season Soybean Success , will share up-to-date, data-driven recommendations that you can use this spring.  Join the new webinar series Science for Success invites you to attend three live webinars, “ Keys to Early Season Soybean Success, ” on March 17, 24, and 31, 2023. Please register and attend these great events. All webinars will begin at noon, Central Daylight Time. March 17, 2023 – When early planting doesn't work out: Do I replant, repair-plant or leave this pitiful stand?  Register: https://go.ncsu.edu/replantregister March 24, 2023 –  What's new in plant

Phyllis Bongard, Extension content development and communications specialist Tar spot of corn was problematic in portions of Minnesota last year. It can spread rapidly, develop quickly, and cause significant yield loss. Since tar spot is a relatively new disease, it’s one to watch for. Drs. Dean Malvick, Extension plant pathologist, and Darcy Telenko, Extension field crop pathologist from Purdue University, tackled these questions from tar spot basics to management in the March 8th Strategic Farming: Let’s talk crops session. Tar spot basics Distribution Tar spot of corn was first discovered in 2015 in northern Indiana and northern Illinois. For the first couple of years, it didn’t cause much concern. By 2018, however, it started to spread quickly around the Midwest. In Indiana where Telenko is based, tar spot can be found in 86 of 92 counties. Between 2018 and 2021, parts of the state saw yield losses between 20 and 60 bushels per acre, with some fields experiencing a 50% loss in 20