Minnesota Crop News

Bruce Potter,  Extension IPM Specialist, Robert Koch - Extension Entomologist, and Gloria Melotto and Sarah Lisak, Graduate students Figure 1. Recording growth data on sentinel plants before placing them in a soybean field. Two species of bean (Phaseolus) were identified as additional hosts of the soybean gall midge (SGM), Resseliella maxima, during the 2022 growing season .  SGM was able to colonize several dry bean ( Phaseolus vulgaris ) cultivars and a lima bean ( Phaseolus lunetus ) cultivar in a study using “sentinel” (i.e., potted) plants placed in a soybean field with a history of significant SGM infestations Rock County (Figure 1). Additionally, SGM-infested plants were found in two navy bean fields in Lac Qui Parle County. The DNA of collected larvae matched SGM as did the morphology of adults emerging from infested navy bean stems. SGM symptoms Figure 2. Soybean gall midge infestation in navy bean stem (Lac Qui Parle County) The external symptoms ...

 Ken Hellevang, Extension agricultural engineer, North Dakota State University Reprinted with permission  Producers may want to condition soybeans that were harvested at lower moisture contents to bring the moisture content up to the market standard of 13 percent. On a 40-bushel-per-acre yield, harvesting soybeans at 9 percent moisture content, rather than 13 percent, is equal to 1.8 bushels of lost weight per acre. At $13 per bushel, that is $0.59 per bushel or $23.40 per acre. In addition, soybeans become more brittle, increasing the potential for handling damage when they are too dry. However, conditioning low-moisture soybeans in storage can damage the grain bin. Conditioning causes the beans to expand, which can damage the grain bin’s bolted connections or even cause the bin to rupture from the increased pressure on the bin wall. The forces on the bin increase more rapidly than by the percentage of moisture content increase. Therefore, a moisture content increase of more ...

By Anna Cates, State soil health specialist, and Jodi DeJong-Hughes, Extension educator Chopping cornstalks higher and leaving larger size residue will make it easier to plant no-till soybeans in spring 2023 Farmers across Minnesota are quickly moving through harvest. Soybeans are mostly done and corn is well underway, if not completed, in most areas. How you leave your fields in the fall is the beginning of planning for the 2023 planting season. Consideration for the very dry weather we’ve had in 2021 and 2022 should be top of mind as farmers plan for a successful spring planting in 2023. Leave a blanket of residue Our soil profile is very dry after record-low rainfall in September. For example, at Lamberton the soil down to 60” is holding less than half of normal . Snow is coming, but the soil can only capture about 25% of the moisture that comes in snow over the next few months. It’s important to leave a blanket of crop residue in the field to hold in the limited moisture you’ve go...

 Craig Sheaffer, Extension forage agronomist, and Nathan Drewitz, Extension educator - crops Planting alfalfa alone or in a mixture with grasses in late summer is recommended because the potential for optimal air temperatures and soil moisture for establishment is good. In addition, there is much less competition with annual weeds compared to spring seedings; therefore’ herbicide use is seldom needed. Typical recommended seeding dates for central and southern Minnesota range from August 15th to September 1st. Drought effects on seedling survival Figure 1. An 8-week-old alfalfa seedling with four fully developed trifoliolate leaves and a unifoliolate leaf. Seedling is undergoing contractile growth leading to formation of a submerged crown. It has a high probability of successfully overwintering. Drought during late August and September will delay germination until favorable soil moisture is available. To germinate, alfalfa seeds must absorb over 100% of their weight in wat...

In this episode of the Nutrient Management Podcast, we discuss surgarbeet nutrient management. How did Minnesota become the nation's top sugarbeet producer? What are some highlights from past sugarbeet nutrient management research in Minnesota? What current studies does the U of M have on sugarbeet nutrient management? What else should growers know about sugarbeet nutrient management? Transcript Guests: Daniel Kaiser, Extension nutrient management specialist (St. Paul) Melissa Wilson, Extension manure nutrient management specialist (St. Paul) Lindsay Pease, Extension nutrient and water management specialist (Crookston) John Lamb, professor emeritus, Department of Soil, Water and Climate (St. Paul) Additional Resources: U of M sugarbeet fertilizer guidelines Cover crop options for pre-pile sugarbeet Is Minnesota really one of the nation's top sugar producers? (Star Tribune) --- For the latest nutrient management information, subscribe to the Nutrient Management Podcast wh...

By: Dan Kaiser, Extension nutrient management specialist High fertilizer prices can lead some farmers to prioritize specific fertilizer applications based on their experience in fields. When it comes to phosphorus (P) and potassium (K), most growers seem to prioritize P even though soil test results may show a greater need for K. We know that P is important for early plant development, especially in corn. Starter fertilizer research has consistently shown that the addition of P early in the growing season can boost early plant growth. In most cases, however, the increased growth does not translate into greater yield. The effect of P on yield is solely dependent on the ability of the soil to supply the nutrient to the crop. If soils test medium or lower in P, there is a greater likelihood that P will increase yield. Interpreting P and K soil test results When we look at all our data, it is much easier to predict where crops will need P compared to K. When I look at a P soil test, I have...

Craig Sheaffer, Extension forage agronomist, and Jake Jungers, Assistant Professor, Department of Agronomy and Plant Genetics, University of Minnesota. Intermediate wheatgrass ( Thinopyrum intermedium ) is the first commercially-viable perennial grain crop. The grain harvested from new varieties is called Kernza®, which can be used as a substitute for annual grains like wheat for production of baked goods, breakfast cereals, and snack bars. Kernza has also been fermented for beer production. “MN-Clearwater” is the first Kernza-producing variety developed in Minnesota and has grain and straw yields potential of 800 lb/acre and 8000 lb/acre, respectively. As a perennial, Kernza is planted once and provides several years of harvestable grain and straw. For more information can be found at https://kernza.org/kernzacap/ In addition to producing Kernza grain, intermediate wheatgrass can be harvested for forage. It has been used as a pasture and hay crop in the western USA for nearly a cent...

By: Fabian Fernandez, Extension nitrogen management specialist Crop harvest is progressing quickly in Minnesota due to the dry conditions. As soon as the crops are out, it is time to start field activities to prepare fields for next year. One of these activities might include nitrogen fertilization. What to apply? In my recent blog post on nitrogen best management practices , I discussed the fact that, for fall applications, the only source that is reliable enough is anhydrous ammonia. This is because all other commercial nitrogen fertilizers have a high potential for loss when applied so far in advance of crop uptake. The reason anhydrous ammonia works for fall applications is that, when ammonia (NH3) is injected, it disperses in the soil, reacting with soil moisture (H2O) within a retention zone, which, depending on soil moisture, can be around three to six inches in diameter. As NH3 reacts with H2O, it forms NH4 and OH-. The OH- creates a temporary increase in soil pH that inhibits...

By: Daniel Kaiser, Extension soil fertility specialist With fluctuating fertilizer prices, it is a good time to review a few principles related to phosphorus (P) availability in soils. We know that P is a critical element required for crop growth and development, and if deficient, the lack of P can significantly reduce crop yield. While application of P fertilizer is common, it is not always required to achieve maximum yield.   Phosphorus exists in the soil in many forms, which vary in crop availability. In fact, crop available P only represents a small fraction of the total P in the soil. When crops take up P, nutrients in less available pools in the soil can move into a more available form, replacing what was taken up by the crop. Crop producers sometimes feel that it is most economical to re-supply the soil with the amount of phosphorus taken up by the crop. However, the soil supply of phosphorus is more complex, and soils testing Very High in phosphorus may be able to fully sup...