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Tuesday, April 25, 2017

Sufficiency or Build and Maintain? Best Bets for Phosphorus Management

Karina Fabrizzi, Daniel Kaiser and Albert Sims

When it comes to phosphorus management, there are two schools of thought: 1) the sufficiency approach, which is designed to maximize economic return for each dollar of P fertilizer applied; and 2) the build and maintain approach, which seeks to mitigate risk by keeping soil test P at a level that minimizes the potential for yield loss. In 2011, University of Minnesota, with funding provided by the Agricultural Fertilizer Research and Education Council (AFREC), set out to test these phosphorus management strategies in long-term replicated field experiments.

Thursday, April 20, 2017

Alfalfa winter injury in Minnesota

Jared Goplen, Lisa Behnken, and Dan Martens

Photo 1. Severely winter-injured alfalfa in Carver County, 2013. Photo courtesy of Dave Nicolai
As the weather warms and the 2017 growing season gets rolling, it is time to evaluate alfalfa stands for winterkill and winter injury. There have been numerous reports of alfalfa fields across Minnesota with varying levels of winter injury and winterkill. Many reports are of low areas in the field suffering the greatest damage, with affected field areas ranging from 10 – 40%. Lack of snow cover along with cold temperatures, freezing and thawing in February, and ice sheeting are some possible causes for winter injury and winterkill this year.

Tuesday, April 18, 2017

Southern Minnesota research and demonstration highlights - 2016

Lisa Behnken, Fritz Breitenbach, and Phyllis Bongard

Photo 1. Field day highlighting weed management at Rochester, MN.
A research team comprised of faculty from Extension, the Research and Outreach Center at Waseca, and the University of Minnesota St. Paul campus conduct field research and demonstration trials annually in southern Minnesota to address local, timely crop production issues. Highlights from the 2016 research report include demonstrating 1) the benefits of using preemergence (PRE) herbicides in corn and soybeans, 2) systems to control giant ragweed and waterhemp, 3) new herbicide technologies used in soybeans, and 4) use of mechanical cultivation for waterhemp control in soybeans.

Friday, April 14, 2017

Cutting Production Cost in HRSW

This post may be a day late and a dollar short as the drills are already rolling across much of Minnesota.  Nonetheless, I'm going to share some thoughts about how to reduce input cost in HRSW without sacrificing much, if any, yield. Consider whether you really need to:

  • Use a seed treatment - only if you have scabby seed with poor germination, know that you had a loose smut in the field that you saved for seed, and/or have a history of common root rot and/or wire worm in a field should you consider a seed treatment.   
  • Use a grass herbicide across every acre - Wild oat is a very competitive weed and already causes yield losses at very low densities.  Fortunate, presence of wild oat tends to be patchy and therefor you may not need a grass herbicide across every acre. The use of Roundup Ready crops has reduced wild oat pressure over the years in many fields, further reducing the need to use a grass herbicide across every single acre. 
  • Use a fungicide mixed in at he time of weed control -  If there is no tan spot, powdery mildew, or stripe rust already present, tank mixing a fungicide at the time of weed control doesn't make sense as the application will not protect any new growth anyway. Research has shown that only when disease was already present at the time of application that an economic return could be expected.
  • Use an insecticide mixed in with your fungicide at the time of your late season disease control - Likewise if there are no or very few aphids present at Feekes 10.51, you shouldn't expect an economic return of the insecticide.
  • Use a pre-harvest glyphosate application to control any late season weeds. Research has shown that in Minnesota, there is little to no advantage to using pre-harvest glyphosate to speed-up dry-down of the HRSW crop itself.

The last inputs to debate their need are fertilizer (in particular N) and the late season fungicides. Ultimately it is not about being the lowest cost producer per acre but being the lowest cost producer per bushel.  

Evaluating Winter Cereal Stands

One of the hardest decisions with growing winter wheat or winter barley is evaluating the amount of winter kill and making the decision whether to keep a stand. Winter cereals are planted in the fall and develops in the spring during relatively ideal conditions for tiller development. Therefore the optimum plant stands of winter cereals can be less than that of their spring counter parts. A stand of 900,000 - 1,000,000 plants/acre or 21 - 23 plants/ft2 will be enough to maximize grain yield.

Winter kill is to be expected in Minnesota. The least amount of winter kill is to be expected with rye, while winter barley is only marginal winter hardy for Minnesota. This past winter was not very cold but snow cover was intermittent which means that some winter kill is likely this year. Roots are generally less winter hardy than crowns and regrowth may be slower than expected.

This past week was probably the first time that evaluating surviving plant density was fairly straightforward. The problem that remains, however, is that winter survival in all likelihood will variable within a field and depending on topography (windblown hilltops having less stand than protected areas of the field). If stands are reduced uniformly across the field, stands of 17 plants/ft2 can still produce near maximum grain yields. If there are bare areas due to desiccation or drown-out consider replanting a spring cereal in those areas.  

Mixing of Hard Red Spring and Hard Red Winter wheat varieties maybe not ideal for management of the field itself as the areas will likely grow and mature at different rates but it should not pose a problem with marketing as they are not contrasting classes of grain as defined by the Federal Grain Inspection Service.

Thursday, April 13, 2017

Spring Management of Cover Crops

By Jill Sackett Eberhart and Liz Stahl

Winter rye cover crop planted in September ready for termination in late May.
Spring management of cover crops is as varied as the different farming operations across Minnesota. The plan of action any given farmer decides to follow will lean heavily towards two things: his or her reason for using cover crops in the first place and the specific cover crops planted.

Monday, April 10, 2017

Got waterhemp? Layer residual herbicides to maintain control

Lisa Behnken, Fritz Breitenbach, Jeff Gunsolus, Liz Stahl, and Phyllis Bongard

Photo 1. Waterhemp in soybeans. Photo: Liz Stahl
Tall waterhemp (Amaranthus tuberculatus) is expanding its reach across Minnesota, and herbicide-resistant populations are becoming more commonplace. Most waterhemp populations have been resistant to ALS (Group-2) herbicides, such as Pursuit, for a while. In addition, glyphosate-resistant (Group-9) populations were first reported in 2007, and PPO-resistant (Group-14) populations were confirmed in southern Minnesota the past two growing seasons. Herbicides in Group-14 include Cobra, Flexstar and Spartan. To add to management challenges, some waterhemp populations have developed resistance to two or all three herbicide groups. In this situation, what herbicide control options are left?

Thursday, April 6, 2017

Key factors for successful corn planting

by Jeff Coulter, Extension corn specialist

Soil conditions

Avoid tillage and planting when soils are wet. In general, a field is ready for seedbed preparation when soil in the depth of tillage crumbles when squeezed. Pre-plant tillage when soils are wet can create a cloddy seedbed that reduces seed-to-soil contact. Achieving excellent seed-to-soil contact is essential for rapid and uniform imbibition of moisture by seeds and uniform emergence. Tillage when soils are wet can also create a compacted layer below the depth of tillage that can restrict root development.

Wednesday, April 5, 2017

Updated nitrogen and agronomic guidelines for corn following alfalfa

By Jeff Coulter, Extension corn specialist

First- and second-year corn following alfalfa usually benefit from increased yield, reduced or eliminated nitrogen requirement from fertilizer or manure, and reduced pest pressure.

Nitrogen management guidelines for first- and second-year corn following alfalfa were updated in 2016 and are available at

Monday, March 20, 2017

Should I reduce the Bt trait acreage in the 2017 corn crop to cut production costs?

Bruce Potter, Extension IPM and Ken Ostlie, Extension entomologist

Figure 1. European corn borer larva and damage. Photo: Bruce Potter
The economics of 2017 corn production have challenged many farmers with minimizing losses per acre. One area that some farmers have targeted for reducing costs is hybrid selection. Planting corn hybrids without Bt protection for European corn borer (ECB), corn rootworm or both will greatly reduce seed costs. However, if not careful, farmers could inadvertently reduce crop revenues if they select hybrids without considering yield potential or insect populations in their fields.

Thursday, February 23, 2017

Herbicide resistance ready workshops rescheduled due to weather

Lizabeth Stahl, Extension educator

Due to the weather, the "Strategic Farming – Are You Resistance Ready" workshops scheduled for Hutchinson and St. James on Friday, February 24, have been postponed.

They have been rescheduled for:
  • March 1 at the American Legion (620, 1st Ave. S.) in St. James, from 9:00 – 12:00 a.m.
    (On-site registration starts at 8:30 a.m.)
  • March 7 at the Event Center (1005 Highway 15 S.) in Hutchinson, from 1:30 – 4:30 p.m.
    (On-site registration starts at 1:00 p.m.)

Wednesday, February 15, 2017

2017 Extension Drainage Design Workshop

The annual Extension Drainage Design Workshop will be held at the Grand Forks County Office Building in Grand Forks, ND March 2 – 3. The workshop is a collaborative effort between the University of Minnesota, and North Dakota State University Extension.

The 2-day workshop starts at 8:00 a.m. and ends at 5:00 p.m. on day two. The workshop will focus on planning and design of agricultural tile drainage systems to meet both profitability and environmental objectives. The course content is taught in a hands-on manner with lots of discussion time.

Monday, February 13, 2017

Jan. 5/19 & Feb. 2 Sauk Centre Hay Auction

by Dan Martens, Extension Educator, Stearns-Benton-Morrison Counties, 320-968-5077 or 1-800-964-4929,

See links to my summaries from Jan. 5 & 19 and Feb. 2, 2017 Sauk Centre Hay Auction
1. Jan. 5, 2017 Summary- All tested loads sold, groups based on hay and bale type and quality
2. Jan. 19, 2017 Summary
3. Feb. 2, 2017 Summary
4. History of Selected Lots
5 Graph of Selected Alfalfa hay groups.
              The 2016-17 season is the RED line now.

Continue reading for other sources of hay market information, related notes, and calendar reminders...

Workshop offers insect management advice under low crop prices, Bt and insecticide resistance

Bruce Potter, IPM specialist

Corn and soybean growers, and those who advise them, often have insect management questions for which the correct answer is, "It depends."

Insecticide resistant populations increase the difficulty of soybean aphid management decisions. Which insecticide group should be used? What about a pre or tank mix? Will seed treatments or earlier applications help?

Wednesday, February 8, 2017

Reminder: Are you resistance ready? workshops offered Feb 22, 23, and 24

by Lizabeth Stahl, Extension educator - crops

Weed management has changed dramatically in recent years. Herbicide-resistant weeds are a significant management challenge, and resistance issues are expanding in scope and geography. Once herbicide-resistance is discovered in a weed population, it doesn’t just go away, and an increasing number of weed populations in MN are resistant to multiple herbicide chemistries or site of action (SOA) groups.

Tuesday, February 7, 2017

Invitation to Complete (Another) Survey

Oats have been a component of horse diets for centuries.  The University of Minnesota Extension Horse and Crop Teams are interested to learn how oats are currently used in the horse diet.  Please help us by completing this 13 question survey by Monday, March 20, 2017:  
Your responses are anonymous and the survey should take approximately 5 minutes to complete.  All horse owners (includes pony, miniature horse, draft horse, mule and donkey) throughout the world are encouraged to complete the survey, but please only complete the survey once.  Thank you for your assistance.    

Learn how to improve cover crop management at workshops

Jake Overgaard, UMN Extension educator

Farmers are gaining confidence in using cover crops more each year. Whether used for soil erosion, capturing nutrients, breaking disease cycles, improving soil health, adding organic matter, or one of the many other benefits, cover crops can be beneficial.

However, in spite of the many benefits, challenges exist. Upcoming workshops in St. Charles on February 28th and in Owatonna on March 2nd will address some of these challenges, including  managing residual herbicide effects, establishing the cover crop and interseeding, and managing manure application timing.

Wednesday, January 11, 2017

Willmar Research Update rescheduled for January 24

Due to weather, the Research Update postponed on January 10 in Willmar has been rescheduled for Tuesday, January 24. The event will be held at the Willmar Conference Center (2100 E. Highway 12)  from 12:30 to 4:40 p.m.

Tuesday, January 10, 2017

January 10 Research Update in Willmar postponed

The Research Update scheduled for today, January 10, in Willmar has been postponed due to weather. The rescheduled event will be announced on Crop News and also on the IAP Research Update website and on the UM Extension Crops Event calendar.

Thursday, January 5, 2017

U of M Extension launches new soil management and health website

by Phyllis Bongard

Balancing the economic and environmental benefits of soil management strategies can be a challenge. U of MN Extension Crops team has launched a website that offers research-based resources to help producers improve soil and crop productivity, while minimizing environmental risks. The website, Soil management and health, features articles and videos in three primary sections:

Wednesday, January 4, 2017

2017 Research Updates for Ag Professionals - January 4-12

by Dave Nicolai, Extension educator

There are five remaining locations scheduled for the 2017 Research Updates: Kasson, Lamberton (January 4 and 5 respectively) and Willmar, Morris and Crookston (January 10, 11 and 12 respectively) from 12:30 pm–4:40 pm. Registration fee is $60. Online registration and session abstracts can be found on our website at or onsite registration begins at 11:30 a.m. at each location.

Tuesday, January 3, 2017

Two Conferences Dedicated to Soil Fertility for Crop Production and Environmental Stewardship

Registration is open for two important conferences dedicated to soil fertility for crop production and environmental stewardship. These events were co-organized by the University of Minnesota Extension and the Minnesota Agricultural Water Resource Center (MAWRC) with a common planning committee to bring the latest advancements in nutrient management presented by University of Minnesota and other university researchers, fertilizer industry experts, and state agency personnel. 

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