Minnesota Crop News

By: Dan Kaiser, Extension soil fertility specialist 
Changes were made to the corn and soybean potassium (K) guidelines in spring 2019. These changes reflect research funded through fertilizer checkoff dollars provided by Minnesota's Agricultural Fertilizer Research and Education Council (AFREC), the Minnesota Soybean Research and Promotion Council, and the Minnesota Corn Growers Association. Funds provided by each were instrumental in evaluating current soil test methods, current critical levels for corn and soybean, and a re-evaluation of rate recommendations. This research represents the beginning of a larger re-evaluation of potassium guidelines for Minnesota.
What should growers be aware of this fall? The primary changes made to the guidelines were to the soil test classifications for corn and soybean, where the critical level for K was adjusted from 160 ppm to 200 ppm for both crops. Recommended K application rates were not changed for corn, as current data suggested no cha…

Groundwater is the major source of drinking water in Minnesota and provides almost all water used for irrigation purposes, making it a key area of focus for natural resource, agriculture, and public health officials. Groundwater contamination (due to agricultural nitrate leaching) and decreased water levels in lakes and streams (due to high groundwater withdrawals for irrigation) are two critical environmental problems in the central sands region of Minnesota.

In a new webinar hosted by the North Central Region Water Network, Assistant Extension Professor Vasudha Sharma talks about irrigation management's relationship with groundwater quality and her on-going research projects aimed at addressing irrigation-induced groundwater quality issues in Minnesota. Her presentation includes some preliminary data from the 2019 growing season.

Watch the webinar on YouTube:



You can also download the presentation slides.

In addition to Sharma, the webinar features Troy Gilmore (University of …

Anna Cates, State soil health specialist, Liz Stahl, Extension educator and Axel Garcia y Garcia, Assistant Professor

Wondering how to do cover crops? UMN Extension, in collaboration with the Midwest Cover Crops Council (MCCC), has produced cover crop “recipes” for two scenarios: Post corn, going to soybean and Post soybean, going to corn.

The recipes are intended to provide step-by-step guidance to some of the lowest-risk starting points for cover crops. They don’t cover the whole spectrum of possibilities, but they can help beginners get most pieces in place to incorporate cover crops into a farm operation. The two recipes were developed to address Minnesota’s most common crop cropping system, the corn/soybean rotation.

The “Post corn, going to soybean” recipe suggests cereal rye, which provides an overwintering ground cover. Soybeans often thrive when planted into standing dead or living cereal rye residue. The “Post soybean, going to corn”recipe suggests oats, which will winte…

Liz Stahl, Extension educator and Anna Cates, state soil health specialist

The Haney test, a test for soil health, is being used to assess biological activity in the soil.  Growers are using these tests to qualify for programs, explore their soil health, and in some cases, plan crop fertility needs. However, many questions remain about interpreting Haney test information, especially for Minnesota soils.

Dr. Anna Cates, state soil health specialist and Liz Stahl, Extension educator in crops, discuss the Haney test in this webinar recorded by the State of Minnesota Board of Soil and Water Resources.

Dr. Cates discusses the various measurements and calculations, while relating results to conditions in Minnesota. Stahl discusses U of MN research comparing results from standard soil testing procedures to the Haney test, and the implications if one were to use the Haney test in determining fertilizer needs.
Watch the Haney test webinar For more information, see “Can soil health tests dete…

Jared Goplen, Extension educator

Temperatures in much of the state have already been below freezing, or will be soon. If you are still planning to graze or mechanically harvest forage on cover crop acres it is important to keep forage species in mind as some species can have toxic effects on animals.
Is my forage crop safe? There is not an issue with grazing or feeding forage of most frosted forage crops. Alfalfa, clovers, peas, small grains, and common pasture grasses have little to no concern of being toxic to livestock. There may be a slightly increased risk of bloat with frosted legumes but these crops do NOT produce toxic compounds like prussic acid following a frost. Typical bloat management will alleviate any issues with grazing legumes.
Sorghum species are primary concern If you are planning to graze or harvest sorghum, sorghum sudangrass, or sudangrass alone or as part of a species mixture, special precautions are needed to prevent health concerns for livestock. Risk is grea…

In this episode of the Nutrient Management Podcast, we discuss fall fertilizer economics. How early is too early when planning nitrogen applications? Are we looking at a year where farmers should be considering inhibitors? What makes the most sense economically for all fertilizers this fall?  Listen to the podcastView the podcast transcript Subscribe to the podcast and never miss an episode on iTunes or Stitcher!

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Support for the Nutrient Management Podcast is provided in part by the Agricultural Fertilizer Research & Education Council (AFREC).