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By Daniel Kaiser
Extension Soil Fertility Specialist

It is important to understand where sulfur that is utilized for crops comes from in order to determine where to best target fertilizer application. In Minnesota, sulfur was not recommended for many crops grown on medium and fine textured soils. Numerous studies were conducted during the 1970's, 80's, and 90's with little to know positive benefits shown except for a limited number of studies where corn was grown on eroded soils. Over the past 10-15 years reports increased as to sulfur deficiencies and research has found that sulfur may be needed for crops most sensitive to sulfur deficiency.

By Daniel Kaiser
Extension Soil Fertility Specialist


Utilization of liquid fertilizer sources placed directly on the seed at planting has become commonplace in many areas of Minnesota. However, low corn prices as well as challenging planting conditions over the past two growing seasons have caused many to question certain aspects of their overall fertility program.  There are a few suggestions that can be used to ensure the best chance for a profitable return on investment

Daniel Kaiser, Fabian Fernandez, and John Lamb
Extension Nutrient Management Specialists

This week of cool weather has made it clear that fall is fast approaching.  The drop in commodity prices will likely cause a few conversations among farmers, consultants, and retailers on what fertilizer to apply for the 2015 cropping year.  Many fields are currently being soil sampled for phosphorus (P), this fall is a good time to consider what is actually out in the field to best target P fertilizer applications.

Nitrogen management for 2015

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John Lamb, Fabian Fernandez, and Daniel Kaiser, Extension Soil Scientists - Nutrient Management


Labor Day has come and gone and now it is time to think about nitrogen (N) plans for next year. This news article will cover some thoughts about fall applications of N.

Soil sampling

If you plan to use a soil nitrate-N test, you need to wait until the soil temperature is below 50°F to get a soil test value that is useful for predicting fertilizer need.

Nitrogen management

The past three years have been challenging for N management for corn. The wet springs have caused larger than normal N losses. In 2014, we saw some of the largest number of acres of N deficient corn in Minnesota in years. The current University of Minnesota N guidelines for corn were based on the use of N best management practices. Fields that had N applied at UMN guidelines may have been short of N, if the fertilizer was applied in the fall. One suggestion for fields with a history of fall N applications with N deficiency problems the last three years is to strongly consider pre-plant spring applications or a split application with some side-dress N before the V8 corn development stage.

by Jochum Wiersma and Albert Sims

Interest in improving grain protein in hard red spring wheat (HRSW) with in-season applications of nitrogen (N) fertilizer may increase this year, since protein premiums and discounts are expected to be greater this year than last. Despite the late planting, the cool and wet weather has created a scenario where the crop may be a bit short on N to maximize grain protein.

There is an intuitive appeal to split apply N (N applied preplant and more N applied during the growing season) in HRSW since the crop takes up the majority of its N between jointing and flag leaf emergence. The practice of splitting the total N fertilizer gift in three or even four separate applications is commonplace in winter cereal production in the maritime regions of Europe, including the countries of Denmark, the Netherlands, the United Kingdom, and France. The objective of split N applications is to supply N when the crop needs it, improve N use efficiency, and consequently achieve maximum grain yield and/or grain protein with fewer N fertilizer inputs.

John Lamb, Fabian Fernandez, and Daniel Kaiser
University of Minnesota Nutrient Management Team

Nitrogen is important for corn growth, and has been a recent concern. This year similar to many years has not had normal weather. Planting has been delayed by moist conditions and cold temperature. Now with the record rainfalls last weekend (May 30 through June 1, 2014), there are concerns that nitrogen has been lost to leaching or denitrification.

By Lizabeth Stahl and Lisa Behnken, Extension Educators in Crops  

Access to results for many of the U of MN crops research trials conducted across the state has now become streamlined with the launch of the new, U of MN Extension Crops Research website.  This one-stop shop can be accessed through the U of MN Extension Crops webpage at www.extension.umn.edu/crops under "Research Reports".

The website contains results for small plot and on-farm crops research and demonstration trials conducted across Southern MN from 2003 to 2013.  You can also access research results for crops trials conducted at Research and Outreach Centers located across the state by clicking on the respective link.  Statewide results for weed science research can be accessed through the "Applied Weed Science" link, and results for the Minnesota hybrid and variety trials can be accessed through the "Minnesota Field Crops Variety Trials" link. 

The Research Reports webpage supplements U of MN Crops websites such as the "Corn", "Soybean", "Small Grains", "Forages", or "Sugarbeets" websites, or the "Nutrient Management", "Pest Management", "Ag Drainage", "Climate and Weather", and "Tillage" websites, where you can find research-based information and resources to help with specific crops-related decisions. 

2014 Extension Drainage Design Workshops

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The annual Extension Drainage Design Workshops will be held in four locations in 2014: January 29 - 30, SDSU Extension Regional Center, Sioux Falls, SD; February 11 - 12, North Dakota State College of Science, Wahpeton, ND; March 5 - 6, University of Minnesota - Crookston, Crookston, MN, and March 18 - 19, Holiday Inn, Owatonna, MN. The workshops are a collaborative effort between the University of Minnesota, North Dakota State University, and South Dakota State University Extension.

The 2-day workshops start at 8:00 a.m. and end at 5:00 p.m. on day two. The workshops 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.

Each workshop is intended for those interested in a more complete understanding of the planning and design principles and practices for drainage and water table management systems, including: farmers, landowners, consultants, drainage contractors, government agency staff and water resource managers. Planning topics include legal aspects, basics of drainable soils, agronomic perspectives, doing your own tiling, land evaluation tools, wetlands, and conservation drainage concepts and techniques. The design topics begin with basic design considerations and progress through individual small team projects, with several hands-on problem-solving examples covering basic design and layout principles, water flow calculations, drain spacing, sizing, and grades. Design principles for lift stations and conservation drainage practices are also considered.

Registration for the four workshops sessions is now available at: www.regonline.com/2014drainage The registration price is $225 (price goes up to $300 about 3 weeks before the start of each workshop), and each workshop is limited to about 65 participants. These workshops have typically filled quickly, so register early to guarantee a spot. Due to seating limitations, on-site registration will not be available on the day of the event. Detailed agendas and additional information will follow shortly and be posted to the registration site.

For more information contact Brad Carlson at bcarlson@umn.edu, or visit www.drainageoutlet.umn.edu

U of M Conservation Tillage Conference in St. Cloud, Feb 18-19

How-to information, expert advice, practical tips

By Jodi DeJong-Hughes, Extension Educator - Crops and Conservation Tillage Conference Coordinator

 

Roll up your sleeves for some practical, hands-on information that will save you soil, time, fuel -- and money. Conservation tillage is the focus of the ninth annual University of Minnesota Extension Conservation Tillage Conference and trade show Feb. 17 and 18, at the Holiday Inn and Suites, St. Cloud, MN. This conference emphasizes proven farmer experience and applied science. Straight from the trenches, learn how heavier, colder soils aren't necessarily the challenge they're made out to be. And, what have long-time no-tillers and reduced-tillage farmers learned that could spare you the same lessons?

John A. Lamb
Nutrient Management Extension Specialist
University of Minnesota

Because of weather, a number of acres of the 2013 sugar beet crop will not be harvested.  It has been a number of years (PIK years) since this many acres have been left un-harvested.  At that time, SMBSC and the University of Minnesota did conduct a number of research studies to answer the main production question:  "What should I do with these fields for next year?" 

By Daniel Kaiser
Fabian Fernandez
John Lamb
Carl Rosen

University of Minnesota Extension Nutrient Management Specialists

The increase number of acres planted to cover crops has raised questions on nitrogen (N) crediting for the 2014 cropping year.  While there are many benefits touted for the use of cover crops, there are a lot of unknowns when determining N credits.  This is especially true for mixes with multiple plant species. 

By Daniel Kaiser
Extension Nutrient Management Specialist


The increased number of corn acres managed with prevented planting in 2013 has resulted in numerous questions about management in 2014.  One major question that arises is the effect of fallow syndrome.  Fallow syndrome is a result of reduced colonization of plant roots by vesicular arbuscular mycorrhizae (abbreviated VAM).  Since VAM are important in the uptake of elements such as phosphorus and zinc, questions arise as to proper management for the following years crops.  However, fallow syndrome does not affect all crops nor will it likely be an issue for all prevented planting acres

By Daniel Kaiser and John Lamb
Extension Soil Fertility Specialists

Many of our earlier planted fields in Minnesota have been exhibiting some significant variation in plant growth and yellowing this spring.  Our conditions in May and early June have been less than favorable for corn growth and for the release of nutrients from organic matter.  Due to the heavy rains nitrogen loss is being increasingly questioned and the decision of whether to side-dress or not will need to be made sooner or later.  There are a few considerations to make when deciding if more nitrogen should be applied.

By Daniel Kaiser

Extension Soil Fertility Specialist

With the variation in conditions we have seen this spring there are a few issues that may show up in fields related to cool and wet soils. Purpling of corn leaves due to phosphorus (P) deficiency and early season interveinal striping due to sulfur (S) may occur if temperatures remain cool and we continue to have frequent rains. I want to take some time and outline these issues and some of the related research that has been conducted in the past five years.

By John Wiersma
Agronomist
Northwest Research and Outreach Center

High pH, highly calcareous soils, common in western Minnesota, restrict the availability of soil Fe needed for optimum soybean growth and yield. On such soils, the amount of Fe fertilizer applied must surpass a threshold before there is sufficient available Fe in the soil solution to induce a positive growth response. Only a limited number of management tactics designed to improve the availability of Fe have been studied with soybean. These include variety selection, seeding density, seed-applied or in-furrow materials, and foliar treatments.

By Daniel Kaiser
Extension Soil Fertility Specialist

Management of Iron (Fe) deficiency chlorosis (IDC) in soybean is seemingly and endless topic of research in soybean growing areas with high pH, calcareous, parent materials. We are just finishing a three-year summary of a series of IDC management strip trials that began in 2010. Our main focus for this work was to study the variability in response for a tolerant and susceptible variety to an oat companion crop and a 6% EDDHA-Fe treatment applied in-furrow (we used Soygreen at a rate of 3 lbs of product per acre). The field areas were selected to have some variation in the severity of IDC.

By Daniel Kaiser

University Extension Soil Fertility Specialist

With the extreme variability in growing conditions there have been some questions regarding the variability in soil test. A project is being launched to establish a series of sentinel plots to study the monthly variation in soil test values over the next two growing season. We are looking for participants that are willing to take samples from a single point within a field and mail them off to us at Saint Paul. The goal of this study is to gain a better understanding of what is happening over the growing season for a number of different nutrients commonly measured.

Daniel Kaiser
Extension Soil Fertility Specialist

I know there are still questions on the application of sulfur for soybean.  Between me and a number of other researchers in Minnesota, we have been working on a number of projects focusing on sulfur management on corn, soybean, and spring wheat.  Recently the soybean research has been fully summarized so I want to take a minute or two to highlight some of the findings to outline where we are at with the current guidelines for fertilizer management on soybean.
Daniel Kaiser
Extension Soil Fertility Specialist
University of Minnesota


Seemingly unpredictable weather conditions each spring inevitably bring up questions on placement of fertilizer with the seed.  Starter fertilizer has played an important role in nutrient management in corn in Minnesota.  However, tools for deciding on how much that can safely be applied have not been widely available.  While these tools can be used common sense is still needed in making a decision on what should be done.

Daniel Kaiser
Extension Soil Fertility Specialist

A few questions arose over the winter as to options for spring applied nitrogen for small grains in areas where fall application was not possible.  One option that was questioned was increasing application rates with the air seeder.  While this does present increased risk, with spring approaching I wanted to take the opportunity to highlight some resources available for helping make decisions on what to apply.  Application with the air seeder allows for more options due to a wide range of seedbed utilized with the various seed spread patters available. 

Soil Testing For K

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By Daniel Kaiser
Extension Soil Fertility Specialist


With spring finally approaching it is a good time to address some questions on soil testing that came up of the winter concerning testing soils in a field moist state versus the standard dried samples that are run through soil testing labs.  First I would like to make it clear that the issue of drying of a soil sample mainly pertains to potassium.  Most other tests routinely run through the lab are not affected by drying of the sample.  The reason why potassium is different is due to its chemistry in the soil.  We currently have finished the second year of potassium studies looking at both testing methods but will be continuing this work for the foreseeable future to gain a better understanding of what is going on within the soil.

Nutrient Management Planner for Minnesota software, version 4.0 for M.S. Windows 7 and Access 2010 is now available on a CD from UM Extension, http://www.extension.umn.edu, at the Extension Store. NMP helps producers and their advisors plan field-specific fertilizer and manure applications that meet crop needs and agency requirements. Recommendations are consistent with current University of Minnesota fertilizer recommendations, the USDA-NRCS-Minnesota 590 (Nutrient Management) Standard, and Minnesota State 7020 Feedlot Rules. The software generates reports that meet NRCS and MPCA requirements, and that serve producers' farm management needs. The software includes a farm nutrient supply and demand calculator to determine the acres needed for manure applications. NMP V 4.0 requires a computer with MS Windows 7 and MS Access 2010. More information is at http://z.umn.edu/nmp.

Fall Nitrogen Application

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By John Lamb
Extension Soil Scientist


This year the crops have matured early and harvest is moving ahead of normal.  With a large amount of the soybeans and corn coming out, thoughts are turning to getting fertilizer applied for next year's crop.  For phosphorus and potassium, there are very few problems with an early fall application.  These nutrients are not mobile in most soils.  The only big concern with a broadcast application of P and K is getting the fertilizer incorporated into the soil so it is in a place for the plant roots to utilize them next spring.  Incorporation also reduces the chances of P and K being lost through erosion.

John Lamb and Daniel Kaiser
Extension Soil Specialists


The corn is tasseling, we are praying for rain, and the week of the 4th of July was hot and miserable.  It must be time to think about evaluating this year's nitrogen management program and making decisions about next year's nitrogen needs.  

By Daniel Kaiser
Extension Nutrient Management Specialist

The dry conditions in March and April have given way to extremely wet areas in some parts of Minnesota.  Since alfalfa stands got an early start this year there were a few concerns popping up early in the southeastern part of the state on areas of fields yellowing.  While there may have been some effects due to the cool weather in April a couple of nutrient could be of concern.

Potassium and Dry Soils

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Daniel Kaiser and Jochum Wiersma
University of Minnesota Extension

Weather conditions have been extremely variable around the state of Minnesota this year. While some areas have experienced near record rainfalls others have still been in the midst of a drought. These differences have brought some interesting questions regarding management of potassium and soil testing in the midst of dry soil conditions.

John A. Lamb and Daniel E. Kaiser
Soil Fertility Specialists

Nitrogen is important for corn growth. This has been a concern on growers' minds since March. First concern was with the poor tillage conditions last fall. Did the nitrogen applied stay in the soil. We attempted to answer that question in a March 18 E-news. At the time of that E-news, drought was the weather condition on everyone's mind. Now with the record rainfalls, there are concerns if nitrogen has been lost to leaching or denitrification.

Daniel Kaiser

University of Minnesota Soil Fertility Specialist

Research on Iron Deficiency Chlorosis (IDC) has been identifying methods to manage the problem for soybeans. Since 2010 research has been conducted using strip trials within farmers' fields. Currently we are looking for a 5 acre area to conduct a field study looking at the effect of Soygreen and oat cover crops on areas of the field that range from no-IDC to severe IDC. Our goal is to determine the economic benefits of the treatments on varying IDC severity within fields planted with two soybean varieties with varying tolerances to IDC.

Daniel Kaiser
Extension Soil Fertility Specialist


Dry fall and early spring soils have led to questions about starter fertilizer application this spring.  While that planting with starter in a dry seedbed can significantly increase the risks, the overall effect will not be known until after planting.  Assessing the situation after emergence will be the best way to determine if damage has occurred due to "pop-up" fertilizer application.  With some corn already planted and fertilizer decisions made there are a few key points to remember when dealing with starter fertilizers.

Daniel Kaiser and John Lamb

Soil Fertility Extension Specialists

The snow is gone and summer is here? The change in weather this spring has allowed for earlier field work to begin. Questions that come to mind include what kind of tillage should I do and do these condition affect me nitrogen management program for corn.

What's Manure Worth?

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UMN Extension has developed a new web-based calculator to determine the value of manure

William F. Lazarus - Extension Economist, Jose A. Hernandez - Extension Educator, and Les Everett - Water Resources Center Education Coordinator. University of Minnesota - Extension

A new web-based tool developed by Dr. William F. Lazarus, Extension Economist and Professor in the Department of Applied Economics, is now available. The web-based calculator may be used to compare the economic value of manure from alternative manure application rates and methods. The value is based on crop nutrient needs for a specific field and crop rotation, fertilizer prices, manure hauling costs, manure type, and application method. In addition to assisting with management of current livestock and crop operations, the calculator can be useful in budgeting new facilities or evaluation of contract production through estimating the effect of manure and manure management on cash flow. The calculations can also assist crop and livestock producer estimate the value of manure that may be transferred or sold from one entity to another.

Livestock producers face uncertain markets and narrow margins. This situation motivates growers to optimize production methods, utilizing all resources including manure. In addition, an increase in the price of commercial fertilizer experienced since 2009, has heightened interest in the use of livestock manure for supplying crop nutrients and has significantly increased the value of manure as a nutrient source.

In recent years more producers have been considering the contribution of manure value to cash flow in livestock operation budgets, and seeking an appropriate market value in exchange situations between livestock producers and crop producers. More crop producers also appear to be seeking manure as a major nutrient source, either by purchasing from a livestock producer or by adding livestock to their operations, particularly swine finishing.

Determining the economic value of the nutrients in livestock manure can be tricky. Nutrients in commercial fertilizer are acquired by paying for the nutrients and a small application charge. With manure you, in effect, "acquire" nutrients by paying for the cost of application, even if you already have ownership of the manure in a storage structure.

Additionally, commercial fertilizer supplies the amount and ratio of nutrients you need or ordered. With manure, you get the amount and ratio of nutrients that it contains, which complicates the determination of a value. Even when a rate that supplies the correct amount of nitrogen is applied, the amount of phosphorous and potash applied may not match what you would have purchased commercially, and amounts applied above crop need probably have no value. In the past, manure application costs often exceeded the value of the nutrients applied. Now, in many situations, the nutrient value in the manure exceeds the cost of application.

The web-based calculator is available at http://z.umn.edu/manurevalue. For more information about manure economics please visit: http://z.umn.edu/manureworth.

Funding for the development of this tool was provided by Minnesota Pollution Control Agency, Section 319 Nonpoint Source (NPS) Management Program from the Environmental Protection Agency.

By Daniel Kaiser
Extension Soil Fertility Specialist

U of M Nutrient Management Website

A new nutrient management website has been launched that houses most of the current fertilizer suggestions and data from the University of Minnesota. This website was made possible by funding from the Minnesota Agricultural Fertilizer Research and Education Council and was put together through a joint effort for several researchers from the University of Minnesota who's research focuses on nutrient management issues for several crops growth throughout the state of Minnesota.  We would like to thank the AFREC program because without them this effort would not have been possible

By Jeff Vetsch and John Lamb. University of Minnesota, Southern Research and Outreach Center and Department of Soil Water and Climate.

Waseca MN, (10/1/2011) - Once soybean harvest is complete many swine farmers begin applying manure to those acres for the next year's corn crop. Manure applications in Southern Minnesota begin in early October and usually conclude by mid November. A significant proportion of the nitrogen (N) in swine finishing manure is in the ammonium-N form. If warm soil temperatures persist after application, the ammonium-N can nitrify and be susceptible to loss via leaching or denitrification. These N losses have negative agronomic and environmental implications. The University of Minnesota recommends fall fertilizer N be applied after soils are less than 50° F at the 6-inch depth. This usually occurs in late October in Southern Minnesota.

By Daniel Kaiser
Extension Soil Fertility Specialist

As the growing season moves forward more questions have occurred about what products to use in side-dress situations. While nitrogen is on the minds of many, sulfur deficiencies are starting to be seen in fields as well. Applying the right product in the right situation at the correct time can be crucial in order to maintain yields and minimize damage to growing plants.

By: Daniel Kaiser and Jeffrey Coulter
University of Minnesota Extension Specialists

With all of the flooded soils and wet fields there likely are questions on denitrification and whether side-dress nitrogen (N) should be applied. The fact is that it can be difficult to predict the amount of N lost. However, two things should be considered when dealing with denitrification:

By Daniel Kaiser
Extension Soil Fertility Specialist

With the recent flooding or late season hail there may be questions on whether a credit can be taken from soybeans not harvested for the next year's crop. Soybeans are a high protein crop which means they can contain a large amount of nitrogen. Average vaules of nitrogen removed in soybean grain are reported at around 3.8 lbs of N per bushel (Source IPNI) for a total of 190 lbs of N in a 50 bu/ac soybean crop. In comparison corn grain would remove about 0.90 lbs of N per bushel and a total of 180 lbs of N in a 200 bu/ac crop.  Can all of this nitrogen be counted on if the soybeans cannot be harvested and are plowed under if they cannot be harvested?  

By Gyles Randall
Southern Research and Outreach Center, University of Minnesota

Nitrogen management practices for corn have become a popular discussion topic lately among growers, dealers, and crop advisors. Record June-July rainfall (16.25" at Waseca) placed intense pressure on N availability for corn, resulting in considerable acreage of lighter green to yellowish green corn in southern Minnesota. This appearance indicates a shortage of N; likely due to denitrification losses of N from the saturated soils during June and July. Scenarios where N losses and N-deficient corn were most apparent include: 1) corn following corn, 2) fall-applied N, and 3) poorly to very poorly drained soils. Based on previous research, applying an additional 50 to 60 lb N/A, especially in the fall, under these "high N loss" conditions would not have been sufficient to meet the N demand of this year's corn.

You are invited to a field day located along highway 71 between Olivia and Blomkest on the southeast corner of the intersection of U.S. Highway 71 and Kandyohi/Renville county line road. Discussions will focus on recent research on iron deficiency chlorosis and a tour of the research plot at this location. Registration for the event will begin at 9 am with speakers starting at 9:30.

By: Daniel Kaiser
University of Minnesota Soil Fertility Extension Specialist


With spring almost upon us there have been questions regarding sulfur application for corn for the upcoming year.  Our current Minnesota recommendations focus on sulfur application to sandy soils that are low in organic matter.  This is mainly due to the fact that sulfate-sulfur is mobile and may leach out of the soil, and that the organic matter is a large storehouse of sulfur and through mineralization this sulfur can become available for uptake in plants.  In the past sulfur was added through atmospheric deposition, applied (but not accounted for) with other nutrients in some commercial fertilizer sources, and in animal manures.  Over time most of these indirect additions have lessened and it is reasonable to assume that there may be deficiencies showing up more prevalent today then in the past.  However, a large research focus has been placed on determining how widespread this problem is and if only certain soils or regions in the area are impacted by potential sulfur deficiencies.  While much of our research is ongoing we have tried to identify key areas to look for in the upcoming cropping year.    

By Daniel Kaiser and Jochum Wiersma

Decisions about the amount of nitrogen to apply in wheat and barley are challenging each and every year as the return per acre is not simple a function of the price of the commodity but also on the quality (grain protein %) of those bushels. There are opportunities to capture premiums for protein but more often than not producers are faced with discounts as the grain protein percentages fall below the market's 14% threshold.  While this was already an issue in 2008 with high yields in Northwest Minnesota leading to lower protein, it was greatly magnified in 2009 with producers reporting grain protein percentages of 10% or less.  This issue is not new since it has been long noticed that yield and protein are inversely related. The amount of grain protein produced per acre appears to be relatively constant over years. In high yielding years the extra starch produced  simply dilutes the total protein produced per acre leading to smaller percentages in the grain  Unfortunately farmers are not paid for total production of grain protein per acre but rather they are paid for concentration in grain.
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