Minnesota Crop News

By: Dan Kaiser, Extension nutrient management specialist I have previously written about the impacts that chloride (Cl) application can have on soybean. Chloride is an essential nutrient for crops but overapplication can reduce yield for some crop species. The most common source of fertilizer chloride is potash, which is commonly applied to supply potassium (K) to crops but is roughly 50% chloride by weight. Chloride has long been known to impact soybean yield in the southern United States but has largely been ignored in the northern U.S. In Minnesota, we have conducted several research projects in the last five years focused on chloride application to soybean, so I wanted to take some time to review what we have found so far and what we are currently studying. How big of an issue is chloride toxicity to soybean? “Toxicity” is a strong word for the issue, but our research has demonstrated that sources of chloride fertilizer can reduce soybean yield. Studies where high rates of chlorid...

Anthony Hanson (hans4022@umn.edu), Extension IPM Regional Educator, and Bruce Potter, Extension IPM Specialist Mid-May to June is typically the time to begin scouting for insect problems in alfalfa. After our cold spring of 2023, alfalfa weevil adults and larvae are beginning to be found in the southern half of the state. Even if larvae are present, insecticide applications may not be needed if populations are not yield limiting or when alfalfa fields can be harvested soon. Cutting exposes the larvae to weather and can greatly reduce numbers.  Remove windrows as quickly as possible. The larvae are concentrated there, and heavy feeding can delay regrowth. (Fig 1). Scouting through June will determine if control surviving larvae need to be controlled. Also remember that insecticide options are more limited compared to previous years with chlorpyrifos (e.g., Lorsban) applications no longer being allowed. Farmers have been seeing a two-pronged challenge to managing alfalfa weevil in re...

Angie Peltier, UMN Extension educator, Bruce Potter, Extension IPM specialist & Anthony Hanson, Extension educator The following information was provided during a 2023 Strategic Farming: Field Notes session. Read further to learn more about this free program that takes place each Wednesday morning throughout the growing season. Black cutworm The same weather systems that carry moist air from the south to Minnesota bring along the lepidopteran pests that cannot survive the Minnesota winter, but spend their winters in southern states. At dusk, black cutworm or true armyworm will begin to fly and are carried north in low-level systems approximately 1,500 feet up, dropping out of clouds toward the tail-end of storms after having ridden north over a couple of days time. Monitoring for these pests is important because weather systems are unlikely to follow the same route to Minnesota each spring. High populations of these pests tend to coincide in an area when there have been heavy sprin...

By: Anna Cates, Extension soil health specialist & A. Marcelle Lewandowski, Senior research and Extension coordinator at the Water Resources Center While there has been a lot of work linking farm management practices with soil health or water quality, few have looked at the connection to both soil and water quality. A new report explores tradeoffs among water quality goals, as well as what we do and don’t know about how soil health practices might change water quality and quantity. Read the full report The report was produced by Soil Health Nexus , a university-led team dedicated to increasing access to research-based soil health knowledge, extension and resources. The report helps planners go beyond the simple idea that “soil health is good for water” to a more nuanced understanding of how to manage soil for healthy water. It also provides beautiful diagrams of the nitrogen and water cycles, which are available for educators to download and use . The report is co-authored by Franc...

Tyler Rice, UMN Extension Educator for Stearns, Benton, and Morrison Counties. The Alfalfa Scissor-cut Harvest Alert is updated regularly as alfalfa growth accelerates. The goal of this project is to alert alfalfa growers to start first crop harvest when the crop is at a level of quality that matches animal nutrition goals while maximizing yield potential.  The alfalfa scissor-cut alert program is not a prescription for any particular harvest date but can be a go-to decision tool for those alfalfa producers that are busy managing other crops in the rotation during one of the busiest seasons on the farm. Extension educators, farmer-cooperators and cooperating agribusinesses work together to collect alfalfa scissor-cut samples from mid-May until final harvest. Attached is the scissor cut progress report ending May 22, 2023: Individual farm results - May 22, 2023 Individual farms cumulated results - May 22, 2023 You can also find up to date information on the project at this link: z.u...

Phyllis Bongard, Educational content development and communications specialist Photo: Liz Stahl Corn and soybean planting progress is close to the five-year average according to the May 15 USDA Crop Progress Report. However, significant rainfall ranging anywhere from two to eight plus inches in southern Minnesota this past week has left many fields flooded. How does that standing water impact crops that have already been planted? What should growers be thinking about for those fields where planting has been delayed? Extension agronomists Jeff Coulter and Seth Naeve joined moderator Liz Stahl, Extension crops educators, for the May 17th Field Notes session to help sort through the issues. Survivability in flooded fields Temperature influences how long crops can survive in a flooded field. Cooler late spring temperatures lengthen survivability so that crops can remain viable for about four days. That timeframe shortens to two- to four-days when temperatures rise into the 80s and 90s...

Tyler Rice, UMN Extension Educator for Stearns, Benton, and Morrison Counties With warmer temperatures and adequate precipitation, the alfalfa crop in Central Minnesota is growing rapidly. This also means that the Alfalfa Harvest Alert Project is well underway. The goal of this project is to alert alfalfa growers to start first crop harvest when the crop is at a level of quality that matches animal nutrition goals while maximizing yield potential. The alfalfa scissor-cut alert program is not a prescription for any particular harvest date but can be a go-to decision tool for those alfalfa producers that are busy managing other crops in the rotation during one of the busiest seasons on the farm. Extension educators, farmer-cooperators and cooperating agribusinesses work together to begin collecting alfalfa scissor-cut samples mid-may until harvest. Attached below is the scissor cut progress report beginning the week of May 14th: Individual farm results - May 14-17 You can also find u...

Co-hosts Dave Nicolai, Extension educator-crops, and Dr. Seth Naeve, Extension soybean agronomist, give an update on planting progress and talk about agronomic issues from the recent heavy rains and early-season insect issues with Bruce Potter, IPM Extension Specialist based out of the Southwest Research and Outreach Center at Lamberton, MN. Bruce has been monitoring black cutworm and true armyworm flights as well as alfalfa weevil of which he reviews how that may be affecting crops in upcoming weeks. In addition, there is a discussion about later planting dates for corn and soybeans as well as diseases to watch out for in flooded or wet soils include soybean sudden death syndrome, Pythium , and Fusarium . Listen to the podcast Black cutworm feeding on corn. Photo: W.M. Hantsbarger, Bugwood.org. Subscribe to the IPM Field Crops  podcast and never miss an episode!