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Showing posts from April, 2017

Do you need to worry about the early seeded small grains?

Yesterday morning the NDAWN station near Eldred recorded a low of 19 degrees Fahrenheit while the NDAWN station near  Stephen dipped as low as 13 degrees Fahrenheit.  Luckily the blanket of snow ensured that soil temperatures were much milder and and at a 4 inch depth the soil temperatures never dropped below 32 degrees Fahrenheit at either location.  Nonetheless I have heard a fair amount of worries about the viability of the seed that made it into ground last week and terms like imbibitional chillingwere mentioned.
Imbibitional chilling is defined as the injury that results from the chilling effect that seeds may experience when they imbibe or absorb water.  The mechanism of this imbibitional chilling injury in seeds is different from chilling or freezing injury of hydrated tissues. The result, however, is much the same as it can result in poor seedling establishment, stand losses, and therefor, ultimately, yield.  Warm season species like corn and soybeans are more susceptible to t…

And then it snowed...any free N with that?

With the 5 inches of snow or so that fell overnight in Crookston, I was asked earlier this morning how much free N we received with that.  Ron Gelderman, former Professor & SDSU Extension Soils Specialist, wrote an article a few years ago for iGrow on how much N is deposited when it snows in early spring. This is a re-posting of his original article.

It's not all about herbicides: Three key tactics for managing weeds

Lizabeth Stahl, Jared Goplen, and Lisa Behnken, Extension educators - crops

Effective cultivation can add durability to weed management programs. Source: Lisa Behnken Weed management tools can be divided into three main categories: mechanical, cultural, and chemical. Historically in conventional systems, chemical control options, or herbicides, have been relied on heavily.

Herbicide-resistant weed populations, however, are limiting herbicide options and effectiveness in many fields. Implementing non-chemical options, such as cultural and mechanical control tactics, can help make weed management systems more effective and durable. Understanding and considering weed biology is a key step in developing a successful program. To develop a more robust weed management program, consider the following three key strategies:

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.

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.

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.  Fortunately, presence of wild oat tends to be patchy and therefore 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 cont…

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 proble…

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.

Got waterhemp? Layer residual herbicides to maintain control

Lisa Behnken, Fritz Breitenbach, Jeff Gunsolus, Liz Stahl, and Phyllis Bongard
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?
The case for layering residual herbicides Once postemergence applications of ALS-, glyphosate- and PPO-herbicides have lost effectiveness against waterhemp, a farmer planting Roundup Ready soybeans would have no viable posteme…

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.

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 http://z.umn.edu/fertilizingcorn.