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Friday, June 23, 2017

What do we know about the value of preemergence herbicides in soybean?

By Ryan Miller and Lisa Behnken

Earlier this spring we shared a couple videos on the lessons we have learned from corn herbicide research at Rochester, MN.  Now we would like to share what we have learned about the value of preemergence herbicides in soybean.  See or video Soybean Preemergence Herbicides: Always Have One Down

We are back in the research plots in Rochester, checking-in to see what we have been learning with our soybean herbicide research plots.  During the past couple of weeks, we shared information on the “reach-back” potential of several preemergence corn herbicide products.  In our soybean plots, we experienced similar weather conditions with a lack of rainfall after the applications of preemergence herbicides.  With that lack of rainfall, the herbicides were slow to activate and we saw an initial flush of weeds emerge, but unlike some of our corn herbicides the soybean preemergence products did not exhibit “reach-back”.  Not to worry, the preemergence herbicides have now activated and are “reaching forward”.  We see that the herbicides are now helping to control future flushes of small seeded broadleaves and grasses, reducing the overall weed pressure.  In addition, they have widened the window of postemergence herbicide application.  Without a pre down we needed our post emergence herbicide applications to go on four days after soybean emergence, with pre’s down we had several weeks to get the post applications on.  We will be following this trial during the 2017 growing season and providing periodic video updates.

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Wednesday, June 21, 2017

Suspect pesticide drift? What to do and how to prevent it from occurring

By Dave Nicolai and Liz Stahl, University of MN Extension Crops Educators

Unfortunately, pesticide applications can sometimes drift onto neighboring crops and vegetation. Damage can range in severity from brief cosmetic symptoms to the inability to market a crop, severe yield losses and/or plant death. Bee kills can also be an issue where pesticide misuse, misapplication, or drift has occurred. The Minnesota Department of Agriculture (MDA) has developed standard procedures to follow when pesticide drift is suspected.

2017 Southern Small Grain Field Days

The University of Minnesota Extension is holding four small grain field days in southern Minnesota June 26 - 27. Each field day will take place at on-farm locations to discuss all aspects of small grain production, including variety performance, plant diseases, and small grain management considerations. Events will include hands-on demonstrations in real field scenarios, with discussion relating to the current growing season. Presenters will include Jochum Wiersma, U of MN Extension Small Grains Specialist and Jared Goplen, U of MN Extension Educator in Crops. Attendees are encouraged to bring any field samples for diagnostics and discussion.

Dates and Locations include:

Monday, June 26, 2017 @ 1:00 PM – Ruth Hoefs/Ron Pomiji Farm, 20676 340th Street, LeCenter – Lunch served at the farm prior to the plot tour.

Monday, June 26 @ 5:00 PM – Gieseke Farms, 53031 Co Hwy 15, New Ulm – Lunch served at Schell’s Brewery following the plot tour.

Tuesday, June 27 @ 1:00 PM – Dave Lochen Farm, 10455 Haus Road, Marty – Lunch served at Pearl Lake Lodge prior to the plot tour.

Tuesday, June 27 @ 7:00 PM – John Gorres Farm, 1065 80th Ave SE, DeGraff – Refreshments served at the trial site.

NOTE: There is no charge and registration is not needed.

Questions about the 2017 South Small Grain Field Days can be directed to Jochum Wiersma, Extension Small Grains Specialist, via email:, or by calling (218) 281-8629, or Jared Goplen, Extension Educator-Crops, via email: or by calling (320) 589-1711

The Supplemental Nitrogen Worksheet for Corn: a tool for in-season nitrogen management decisions

Greg Klinger, Fabian Fernandez & Dan Kaiser 

Wondering whether you should apply supplemental nitrogen to your corn fields this year? Find your answer with University of Minnesota Extension’s Supplemental Nitrogen Worksheet for Corn. Meant to be used in early to mid-June, this useful tool asks 3 simple questions of growers and provides a score that rates the need for additional nitrogen fertilizer.  High scores mean that supplemental N should be applied, medium scores suggest taking a “wait and see” approach, and low scores mean no supplemental N should be needed.

Thursday, June 15, 2017

Tips for Accurate Pre-Sidedress Nitrate Tests

Fabian Fernandez and Daniel Kaiser

The pre-sidedress nitrate test (PSNT) is a tool for making decisions on supplemental nitrogen application. Taken during June prior to side-dress N application around the V6 stage of corn growth, the PSNT offers a way to assess insufficient N in the soil. It offers guidance for efficient N management, but only if carried out correctly. Watch our video with Extension Nutrient Management Specialist Fabian Fernandez and read on for tips to make the PSNT count.

Wednesday, June 14, 2017

Temperature inversions: Something to consider before spraying

By Ryan Miller and David Nicolai

Fog developing in an early morning temperature inversion. Source: Ryan Miller
We have produced a video, Temperature inversions: Something to consider before spraying (, that discusses the development of temperature inversions, which can affect the drift, or off target movement of pesticides during post emergence applications. Issues relating to temperature inversions and how they develop is summarized below. This content comes to us from neighboring land-grant universities (see references for detailed source information).

Tuesday, June 13, 2017

The downstream effects of hail on pest management

Bruce Potter and Dean Malvick

Hail-damaged corn, Renville County, June 11, 2017. Photo: Matt Wordes
Hail has hit a several areas of Minnesota, including Southwest Minnesota. For those that have not yet seen the article, U of MN Extension recently released revised information on assessing damage and yield loss: Hail damage to corn and soybean. For some farmers and their advisers, the damage is severe or light enough that decisions are easy. For others, in a couple days there will be indecision and a desire to try to help the crop out.
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