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Summer re-seeding (or seeding) of alfalfa

 Craig Sheaffer, Professor, Department of Agronomy and Plant Genetics, Krishona Martinson, Extension equine specialist, and Jared Goplen, Extension educator-crops. Figure 1. An alfalfa field seeded in early May with an oat companion crop. Forage was cut and baled in mid-July. The green vegetation in the field is lambsquarters and regrowth from the oats, whereas the alfalfa has failed to establish (Photo taken late July). The drought in many regions of Minnesota caused significant problems with alfalfa establishment this spring (Figures 1 & 2). Although periodic rainfall has occurred, most of the state continues under moderate to severe drought ( ).  On some farms, alfalfa seeds germinated this spring but failed to thrive due to limited moisture. This has resulted in thin or uneven stands in many fields.  In some cases, areas of fields with heavier soils produced partial alfalfa stands while lighter, sandy soils have no alfalfa. Drought-toler
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How to calculate a nitrogen credit from irrigation water

By: Vasudha Sharma, Extension irrigation specialist & Fabian Fernandez, Extension nitrogen management specialist Nitrate (nitrate-N) is commonly found at some level in irrigation water. For corn in Minnesota in a normal irrigation year, when nitrate concentrations in irrigation water are below 10 parts per million (ppm), or 10 milligrams per liter (mg/L), we don’t recommend making adjustments to your fertilization plan. This is because the University of Minnesota’s corn fertilizer guidelines already account for this. If nitrate concentrations are greater than 10 ppm or the amount of irrigation during the season is substantially greater than normal, the nitrogen added through irrigation should be accounted for because: Excess nitrogen in some crops can result in vigorous and excessive vegetative growth, leading to uneven or delayed maturity and reduced quality. The nitrogen credit from irrigation water means you can save money on nitrogen fertilizer costs, especially in dry years l

Should you apply sulfur fertilizer for alfalfa?

Photo credit: Jared Goplen/University of Minnesota Extension By: Dan Kaiser, Extension nutrient management specialist Did you know that alfalfa can remove more sulfur from the soil in a year than a corn crop? However, past research on forage crops has been inconclusive as to whether sulfur fertilizer is required for highly productive alfalfa fields with organic matter (OM) concentrations greater than 4%. In addition, most of the research out there on this topic is based on one-year trials, which may not be long enough to establish the benefits of sulfur for growers pushing for higher tonnage in their alfalfa production systems. That’s why we sought funding from Minnesota’s Agricultural Fertilizer Research and Education Council (AFREC) for a multi-year study on sulfur fertilizer sources and application rates. The project, at the Rosemount Research and Outreach Center, is currently in its third year. Combined with another trial in Rosemount from the 2019 growing season, Minnesota-based s

Sand Plain Research Farm Irrigation and Nutrient Management Field Day

University of Minnesota Extension’s 2021 Sand Plain Research Farm Irrigation and Nutrient Management Field Day will take place on Monday, August 30th from 4pm to 7:30pm . This event is free and dinner will be provided . Registration is required. Please register by August 20th. Register now The Sand Plain Research Farm (SPRF) is a unique coarse textured-soil site in central Minnesota featuring irrigated and non-irrigated agronomic research. The current SPRF research site includes 345 acres of cropland. Of that, 290 acres are irrigated. The farm is outfitted with eight irrigation systems (three laterals and five center pivots). All three of the lateral irrigation systems and one of the center pivot systems are equipped with variable rate irrigation (VRI) technology. Presentations Vasudha Sharma, Ph.D. - Irrigation management strategies for profitable corn production and water quality protection in Minnesota Central Sands Yuxin Miao Ph.D. - Proximal and remote sensing technologies for cor

Recent findings of the Western Minnesota IPM Survey

By Angie Peltier, Anthony Hanson and Jared Goplen, UMN Extension educators. UMN Extension soybean IPM scouts traveled across northwest and west central Minnesota completing another week of data collection on July 16. When visiting each soybean field, scouts first sweep for grasshoppers in the grassy area next to the field and then begin walking in a zig-zag pattern throughout the field, stopping along the way to growth stage the crop and examine 31 plants for soybean aphids, aphids that have been colonized by parasitic wasps, bean leaf beetles and spider mites. Growth stages. For the most part, soybeans in northwest counties were either just beginning to bloom or had reached full bloom ( Figure 1 ). Further south, soybeans had all reached full bloom with some crops reaching the full pod growth stage. Figure 1 . Growth stages of soybeans scouted between July 5 and 16 as part of the UMN Extension 2021 soybean IPM survey. Map source: NDSU IPM program. Grasshoppers. Scouts us