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Showing posts from April, 2022

IPM Podcast: Pesticide regulation in the news for the 2022 growing season

  Welcome to the IPM Podcast for Field Crops. Subscribe to the podcast and never miss an episode on your favorite platforms, such as iTunes , Google Podcasts, and Spotify. This Podcast is sponsored by UMN Extension Integrated Pest Management (IPM). In this week’s podcast, we feature: Dr. Trisha Leaf , Research Scientist with the Minnesota Department of Agriculture Pesticide and Fertilizer Division. Click here to listen to the podcast Dr. Leaf discussed how pesticide regulation works at the federal and state level. The Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) is federal law that governs how pesticides are registered, distributed, sold, and used in the U.S (i.e., "the label is the law"). Pesticide registration is also when tolerance levels are determined for food crops and what label requirements are needed for in-field use to prevent pesticide residues occurring above the maximum residue limit or other safety concerns. Recently, tolerances of a common

To Treat Seed or Not to Treat Seed is a Question

Every year I get asked the question if a seed treatment is needed for small grains.  Invariably my answer is that: Yes, if your seedlot carries a seed-born disease like loose smut of wheat.   Yes, if you have a scabby seedlot  Possibly, if you have a known history of wireworms in a field Possibly, if you've been in continuous small grains  (>2 years) and you started seeing a higher incidence of root rots like common root rot, Fusarium crown rot, or take-all. In all other situations, seed treatments are much like life insurance; it pays only when disaster strikes during the very early stages of the crop and initial stands are reduced enough that grain yields are reduced because of the lower initial stands that could not be compensated for by additional tillering from adjacent plants.  The three major soilborne fungal diseases that reduce initial stands in Minnesota are Pythium damping-off, common root rot (CRR), and Fusarium crown rot (FCR). While pythium likes cold and wet condi

Wind erosion and nutrient loss: How much soil is moving and what could that cost farmers?

By: Mehmet Ozturk, graduate research assistant, & Anna Cates, Extension soil health specialist Two ongoing studies are measuring how much soil is being blown across different fields, and how much nutrients lost with wind erosion might cost farmers. Wind erosion Sometimes you can see the soil leave your field, washing into the ditches with a spring rain or blowing across the roads and getting through the windows of houses. Other times it’s more subtle and slow. Most hilly fields have knobs with lighter soil due to long-term wind, water, and tillage erosion. Aside from on-farm nutrient losses, wind-eroded sediment can cause traffic accidents, increase respiratory problems, and change how water moves on the landscape. When snowpacks mix with dust, they absorb more sunlight and melt earlier. Technically, wind erosion is defined as the transportation of soil particles from one location to another, and it easily occurs where soil is bare, loose, and dry. It is difficult to measure where

Alfalfa seedling tolerance to freezing

Craig Sheaffer, Extension forage specialist, and Jared Goplen, Extension educator - crops Can alfalfa germinate in a block of ice? Alfalfa seedlings. Scientists in the early 1900’s reported that alfalfa seed did germinate when surrounded with ice. We recently confirmed that with seed from modern alfalfa varieties that varied in fall dormancy when they germinated near the freezing point of water (31.3 F to 32.2 F). This temperature is much lower than the optimum minimum germination temperature of 60 F. The ability to germinate at very low temperatures may be derived from alfalfa’s origin in the Fertile Crescent where early establishment when moisture is available may have a competitive advantage. At very low temperatures (<40F), germination of alfalfa seed is much slower when compared to 40 to 50 F. We found that at 32 F, it took 15 days to reach 50% germination. At 50 F, 50% of seeds germinated in just 3 days. Individual seedlings will emerge slowly at low temperatures, meaning a

Strategic Farming: Field Notes launches May 11

The growing season is filled with a host of challenges, including insect, disease, and weed pests, resistance concerns, agronomic issues, and soil fertility questions. The Strategic Farming: Field Notes program is designed for farmers and agricultural professionals as a weekly webinar program addressing all your crop-related questions in real-time in an interactive, discussion-based format. The Field Notes program will begin on May 11th and continue throughout the 2022 growing season on Wednesday mornings from 8:00 – 8:30 a.m. The program will feature a live webinar with interactive discussion with attendees, addressing in-season cropping issues as they arise. Weekly topics will be announced on the week of the program, and may include topics related to soil fertility, agronomics, pest management, equipment, and more. Can’t make the live session? No problem. The discussion-based series will be posted immediately following the webinar to your favorite podcast-streaming service to liste

Can you manage your way out of corn rootworm problems? It's complicated!

Bruce Potter, Extension IPM specialist Parts 3 & 4 Part 3 - Developing a management plan A yellow sticky trap used to monitor corn rootworm beetles. Early corn planting and dry springs tend to favor the survival of corn rootworm larvae. Those same conditions tend to reduce the effectiveness of at-plant insecticides. Rootworms do have some weak points. NCR eggs are relatively cold-tolerant but prolonged cold, open winters can cause mortality to WCR eggs wintering in the soil. Larval mortality can occur if soils are saturated when small larvae are trying to enter corn roots. By late July and August, you will know how successful both corn rootworms and your corn rootworm management strategies were. Monitoring rootworm populations   For several years, Dr. Ken Ostlie and I have been examining methods to monitor rootworm populations using yellow sticky traps and a network of farmer, industry, and Extension cooperators. The cooperators receive traps and management information for the fiel

Growing corn on irrigated sandy soil: Three ways to reduce nitrogen loss

By: Jessica Wayment, graduate research assistant, & Fabian Fernandez, Extension nitrogen management specialist Nitrate leaching is a major concern in coarse-textured agricultural soils because it can cause economic losses for farmers and contaminate groundwater. While some nitrate leaching may be inevitable when growing corn on sandy soils, there are several management strategies that can be implemented to limit nitrate loss. Here are some key takeaways from a recent five-year study looking at three major factors impacting nitrate leaching: drainage, nitrogen availability, and cropping system. Drainage Nitrate leaching occurs when rainfall, irrigation, or the two combined exceed the water holding capacity of the soil and the excess water drains below the root zone, carrying nitrate with it. Climate models for Minnesota project a greater likelihood of extreme precipitation events during the spring and summer months. This means that it will become increasingly

Disposal Requirements for Treated Seed

I know......There has not even been a single seed put in the ground so far this spring. Nevertheless, the Minnesota Pollution Control Agency (MPCA) just released a new fact sheet that details the requirement for disposal of treated seed in Minnesota. The fact sheet can be found here .   MCPA has the jurisdiction in this case as any quantity of treated seed that is not planted is considered industrial solid waste. Just take a minute to read it and familiarize yourself with the do's and don't of treated seed disposal.  

Alfalfa and red clover can supply N for following crops when grown for one year

Craig Sheaffer, Extension forage specialist, Jared Goplen, Extension educator-crops, Jochum Wiersma, Extension small grains specialist, and Dan Kaiser, Extension nutrient management specialist Red clover. Photo: Edwin Remsberg, USDA-SARE Forage legumes like alfalfa and red clover together with manure were once the only way to provide additional nitrogen to non-legume crops. The ability to synthetically produce nitrogen fertilizers greatly decreased agricultural reliance on traditional nitrogen sources beginning in the early 20th century. Legumes still can provide valuable nitrogen to today’s cropping systems. Legumes also contribute a non-nitrogen rotation effect due to addition of soil organic matter and improvement in soil health. Corn grown following alfalfa stands that are 2+ years old (and contained at least 50% alfalfa) require no nitrogen fertilizer on many soils. Red clover nitrogen credits are less than for alfalfa. Details of nitrogen fertilizer rates following legume cr

Potassium management: Maps showing soil clay type could help Minnesota farmers

By: Leanna Leverich, graduate research assistant, & Dan Kaiser, Extension nutrient management specialist Soil textural triangle   When farmers think of clay, they often think of soil texture (clay loam, clay, sandy clay loam, etc.), which is important for making nutrient management and overall field management decisions. However, soil texture classifications only describe how much clay, silt, and sand there is in a soil. They don’t tell us anything about what kind of clay minerals are in the soil. The clay in soil actually contains many different types of clay minerals. Knowing which clay mineral type is dominant in a field could help Minnesota farmers decide how much potassium (K) fertilizer to apply. Clay minerals: What are they and why do they matter? Particle size and description  Clay minerals are more complex than sand and silt particles. First, sand and silt particles sit in the soil like marbles stacked in a jar with the space in between for water and air movement (pore s

Strategic Farming talks taming soil fertility and weed management input costs

 Phyllis Bongard, Educational content development and communications specialist Photo: Jared Goplen As fertilizer and herbicide costs increase, what kind of strategies can growers use to tame these input costs in 2022? Brad Carlson, Extension educator and Dan Kaiser, Extension nutrient management specialist joined Extension weed scientists Tom Peters and Debalin Sarangi for the final webinar of the series. The March 30 session of Strategic Farming: Let’s talk crops! was moderated by Extension Educators Dave Nicolai and Liz Stahl. Taming nutrient management input costs With planting dates quickly approaching, Carlson gave a quick recap on current conditions. In an average year in Waseca, frost is typically out of the soil at 6-inches in March. This year, however, soil is still frozen at 12 inches. Take a look at the National Weather Service’s Frost depth map for more information. A significant portion of eastern Minnesota still has a moisture deficit going into the growing season.

What Does Easter Have to Do With an Early or a Late Spring?

I have heard on more than one occasion that a late Easter means a late start of the growing season. However, if I look at the calendar date of Easter and the first reports of seeding wheat in Minnesota from 1981 through 2021, the relationship across years between the two dates is very weak and statistically non-significant (Figure 1).  It appears that very little if any small grains will be seeded before Easter this year as a major storm is predicted to roll across much of Minnesota later today. The next question you ask yourself is whether is getting too late already to seed spring wheat, barley, and oats in southern Minnesota.  For now, I would say, not yet.  The planting window for southern Minnesota really does not close until about the first week of May (Table 1). Figure 1 - Relationship between the calendar date of Easter weekend  in days after January 1st and the first wheat being seeded in Minnesota as reported by USDA-ARS between 1981 and 2021. Table 1 - Optimum and last recom

Can you manage your way out of corn rootworm problems?

 Bruce Potter, Extension IPM specialist Parts 1 & 2 Part 1: Tool selection Corn rootworm management was one of the crop pest problems I puzzled over this past winter. Recently, some warm weather got me thinking about changing the oil and blade on my year-old lawnmower. It’s a replacement for an old machine that suffered from a lack of Zen during my maintenance efforts. Most repair efforts involved a couple of screwdrivers and pliers ‒ the only tools I could count on finding on the garage bench. Multi-purpose, they did duty as crude hammers and pry bars in a pinch. The sets of socket and box end wrenches, including those special metric jobs, and multiple sizes of screw bits, reside safely in the tool chest back at the house, but those precision tools don’t get much use. The few tools on the bench could usually be made to work, and who has the time to walk back from the yard to get the right-sized wrench? The old mower had bolt heads where an active imagination could still find six