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May 2011 Archives

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:

Central MN Alfalfa Harvest Alert May 26 Update

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By Dan Martens, Extension Educator, Stearns-Benton-Morrison Counties

Check "continued reading"   for an update of PEAQ and Forage lab data from fields checked on Thursday May 26 as of Friday May 27 about 5:00 p.m. The NORMAL technology failed me in trying to attach a pdf document. You'll have to look back at the first May 26 posting for previous test results on individual farms.

Weather. Notes at the end of the report include comments from Extension Climatologist Mark Seeley about weather prospects over the next couple of weeks.

Alfalfa Weevil. Notes at the end of the report include a couple observations about alfalfa weevil also.

Sauk Center Hay Auction Reports May 2011

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By Dan Martens, Extension Educator, Stearns-Benton-Morrison Counties
This information is from Hay Auction held at Sauk Centre MN ON May 5 and 19.
An additional Auction will be held on June 2.

SC Hay Auction 05 05 2011.pdf   A list of all tested hay lots and bedding materials sold on May 5... grouped by kind of hay and type of bale ... cost per  pound of dry matter and cost per RFV point are calculated.

SC Hay Auction 05 19 2011.pdf Same for May 19 auction

History of Selected Lots 2010 2011.pdf    A summary of auctions held this year: Medium Square Alfalfa 101 to 200 RFV divided into 25 RFV groups, and bedding material.  Sometime during the next couple of weeks, I'll calculate averages through the 2010-2011 season.

Graphs of Med Sq Alf 2001 to 2011.PDF     Line graphs of auction seasons from 2001 to 2010.

Throughout the year, you can also get USDA Hay Market reports at

Central MN Alfalfa Harvest Alert May 26

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By Dan Martens, Extension Educator, Stearns-Benton-Morrison Counties 800-964-4929
Click    Alfalfa Field Data 05 26 2011.pdf    for Alfalfa PEAQ and Scissors-Cut samples from Thursday May 26. More results will be received on Friday afternoon and an update should be posted later Friday afternoon or evening. Then we will not have new results until Tuesday afternoon May 31.

"continued reading" offers an note from Extension Climatologist Mark Seeley aboiut weather prospects over the next 2 weeks and another note on "alfalfa weevil."

Heat Canker and Frost Damage in Small Grains

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The title of this short article may seem a paradox, but leave it to a Minnesota spring to create the conditions for both problems within a day or two. Last night's lows may have caused some frost damage in northwest Minnesota. Fortunately, for spring wheat and barley the damage is cosmetic and will not require replanting. The reason for this is as simple as it is elegant. The tender growing point from which all leaves and eventually the spike is produced is insulated and protected by the soil. Up the approximately the 5-leaf stage the growing point is located at the crown at ± 1.5 inch below the soil surface. The crown is easy to recognize as a hard knob from which both roots as well as leaves start. This evolutionary adaptation to keep the growing point hidden and protected from the elements is precisely why small grains fit so well in this area. Frost damage will initially have a dark green, water soaked appearance that will quickly dry out, leaving the tissue white to tan (Photo 1). Frozen and dried up leaf tips will often break off with a little wind and give the field a very raged appearance. New growth should not show any symptoms.


Photo 1 Frost injury on young barley plants

The sunny, windy weather and big temperature swings expose the young seedlings to a second abiotic stress. The heat at the soil surface can cause heat canker. The tender young tissue at the soil surface basically will 'cooked' and this appears as a yellow band that is slightly constricted (Photo 2). As the leaf continues to grow, this yellow band (1/8 - 1/4") moves upward and away from the soil surface. If the conditions last for more than a day, repeated bands can become visible. As with freeze injury, the tips of leaves may break off at the yellow band and give a field a very ragged appearance. Damage from heat canker is temporarily and should not affect further growth and development.

Heat-Canker.pngPhoto 2 Heat Canker on just emerged wheat

Author: Dr. Jeff Stachler U of MN Extension and NDSU Agronomist - Sugarbeet/Weed Science

Sugarbeets have emerged or are beginning to emerge. That means it is time to begin postemergence herbicide applications to sugarbeet. Timing of the first postemergence herbicide application is the MOST critical weed management tactic, regardless of the type of sugarbeet planted.

Ground Rolling Soybeans in 2011

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By Doug Holen and Phil Glogoza, University of Minnesota Crop Extension Educators.


Producers have been pushed to accomplish as much planting possible in the little time given as calendar dates roll by in a late spring start.  The goal has been to get the seed in the ground when fields are ready for equipment and between rain events.  It has been common across the state in previous years for producers to ground roll fields within hours of planting soybeans.  However, the push to plant between rain events and other delays this year has left many fields unrolled.  The question is, "Can I still roll without causing significant damage to the plants or stand?"      

Switch from corn to soybeans? Not so fast!

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Central MN Alfalfa Harvest Alert May 23 Update

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By Dan Martens, U of M Extension Educator, Stearns-Benton-Morrison Counties
Click on Alfalfa Field Data 05 23 2011.pdf
to get an update of alfalfa scissors cut PEAQ and lab data from cooperating farms on May 23 ... as of 5 p.m. on May 24. All farms are in now.

Early stage buds are starting to show up in some fields. As we get alfalfa moving toward 22 to 24 inches tall (in some fields now), some people will start looking at soil moisture and weather conditions that might be suitable for harvest of better dairy quality hay, depending on ration strategies and past experience.

The notes at the end of the report includes a couple thoughts about Alfalfa Weevil development.

By Gary Hachfeld, University of Minnesota Extension
Originally published in Ag News Wire

Farmers who are prevented from planting their crops due to wet spring weather can manage this risk if they have purchased federal crop insurance.

Yield protection, Revenue Protection and Revenue Protection with Harvest Price Exclusion policies all include prevented-planting coverage. There is no prevented-planting coverage with Group Risk Plan or Group Risk Income Protection insurance.

By federal definition, prevented planting is failure to plant the insured crop with the proper equipment by the final planting date designated in the insurance policy. Final planting dates vary by crop and by area. For example, the final planting dates are generally May 31 for corn, June 10 for soybeans, and May 15 to June 5 for wheat, depending on location. Farmers should check with their insurance agent if they have questions on the final planting date.

Farmers who have had an insurance policy in the past are eligible for prevented-planting coverage. New policyholders are also eligible if their loss occurred after the sales closing date and all other prevented-planting requirements are met.

If a farmer is prevented from planting a crop by the final planting date, there are several choices. Those choices include:

  1. Plant the crop during the late planting period, which is generally 25 days after the final planting date. There is a reduction per day in coverage using this choice.
  2. Plant the crop after the late planting period with no reduction in the insurance coverage.
  3. Leave the acreage unplanted and receive a full prevented-planting payment.
  4. Plant a cover crop and receive a full prevented-planting payment and graze or hay the crop after November 1.
  5. Plant another crop (not the insured crop) after the late planting period or after the final planting date if no late planting period applies. Hay or graze a cover crop, but not before November 1, and receive 35 percent of the prevented-planting guarantee.

There are many provisions included in the prevented-planting provision of federal crop insurance. Keep good records and documentation. When in doubt, read your crop insurance policy or contact your crop insurance agent. Any small infraction of any of the provisions can result in no indemnity payment and loss of the crop insurance protection you purchased.

See more on the late planting page.

Central MN Alfalfa Harvest Alert May 23

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By Dan Martens, U of M Extension Educator, Stearns-Benton-Morrison Counties
Click here Alfalfa Field Data 05 23 2011.pdf for information from field sampling on May 23 that we have back as of 4:30 on Monday afternoon.
The first page shows information received so far for all farms on May 23. The next pages show information for each farm individually so far this spring. These are listed generally from south to north: Scott, Carver, McLeod, Meeker, Wright, Stearns, Benton, Morrison Counties.
Samples from some farms are mailed to the forage lab and it takes another day to get information back.

Central MN Alfalfa Harvest Alert May 19

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By Dan Martens, U of M Extension Educator, Stearns - Benton - Morrison Counties
I'm posting here a link to data from fields checked on May 19. The first page shows information for all farms for May 19, followed by all tests so far listed by individual farms. These are listed generally from south to north: Scott, Carver, McLeod, Meeker, Wright, Stearns, Benton, Morrison Counties.
This information was updated around 3:30 pm. on Friday May 20.
Click here for the updated May 19 report Alfalfa Field Data 05 19 2011.pdf

Central MN Alfalfa Harvest Alert Report

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By Dan Martens, U of M Extension Educator, Stearns-Benton-Morrison Counties
I'm posting a link here to data from fields checked on Monday May 16. Barry Visser from Vita Plus sampled at the Poppler farm in Wright County where alfalfa measured 18 inches; and says most fields he has checked are in the range of 15 to 17 inches for tallest stems.
For the May 16 Field Data Report click here Alfalfa Field Data 05 16 2011.PDF

by Dan Martens, Extension Educator, Stearns-Benton-Morrison Counties
The information we have so far from sampling on Monday morning May 16 is:
In Wright County, at the Poppler Farm near Waverly, tallest stems 18." With favorable weather, that kind of field could be ready to harvest within the next two weeks.
At the Krause farm west of Buffalo 15.5"
In Benton County at the Scapanski Dairy northeast of Sauk Rapids and at O & S Dairy east of Rice 14 to 14.5 inches.
Of course feed quality numbers are much higher that we want for harvest yet, but we can see as other field work has been at a standstill, the hay crop has been making some progress. I'll post a chart with feed quality tests as we get more of that information. More information about doing scissors cut sampling on your own farm, using PEAQ sticks, or using this information can be found at

Emergency Options for Seeding Small Grains

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As the wet and cold weather continues to delay fieldwork and the window for small grain seeding is closing, you may be considering alternatives. Broadcast seeding methods, whether by air or with a pneumatic fertilizer spreader (floater), are an emergency option you can consider if you plan to cstick with small grains. The chances of success are greatly improved when you heed the following:

  1. The broadcasted seed will need to be incorporated with some light tillage. Tillage prior to seeding is less critical if fall tillage resulted in a smooth and even field. A tillage operation following the broadcasting of seed is needed to incorporate the seed. Incorporation is essential to create seed to soil contact needed for successful germination and seedling establishment. Harrowing often is enough. Incorporation of the seed with tillage will result in variable seeding depth.
  2. The seeding rate will need to be increased as the stand loss percentage due to seed placement that is too deep or too shallow will increase. Research in Ohio and Wisconsin with winter wheat showed that the seeding rate needed to be increased with 15%. Local experiences with spring wheat point to an increase between 10 and 20%.

As stated already, broadcast seeding is an emergency option. Using a floater has the advantage that you will be able to spread fertilizer in a single pass. Expect uneven and often delayed emergence. Barley will be most sensitive to incorporating the seed too deep, while oats will have the most tolerance to seed being placed deeper than the optimum 1.5".

Managing a late start to soybean planting

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By Dave Nicolai and Seth Naeve
Originally published in Ag News Wire

With only 28 percent of corn acres planted prior to May 9 in Minnesota, growers face the difficult decision of when to begin planting soybeans in order to maintain adequate yields.

Soil conditions are of primary importance when considering delayed planting.

Soil conditions and soil temperature

Soil conditions at and after planting usually make a difference in how successfully the crop is established. Soil compaction and smearing is a concern when pulling implements and the planter through, or driving on, wet soil.

To limit soil compaction, keep axle loads under 10 tons and properly maintain air pressure in the tires. Not only does this help the soil, but it will help your tractor run more efficiently and with less slippage. On wet soils, use the lightest tractor that can get the job done.

Soybean has delicate seed, so it benefits when planted about 1 1/2 inches deep, modestly firmed into the seed furrow, covered by relatively loose soil, and into soils with temperatures of 60 to 70 degrees. As of May 9 , soil temperatures at the 2-inch depth averaged 61 and 56 degrees, respectively, at University of Minnesota Research and Outreach centers in Lamberton and Waseca.

The lack of oxygen in saturated soils and the formation of a soil crust of even modest strength can almost eliminate soybean emergence. Therefore, it is important to pay attention to the five-day forecast prior to planting. Planting in cool and wet conditions may lead to poor germination and seedling diseases such as pythium. These problems are magnified by extended cold and rainy periods after planting.

University of Minnesota Extension research indicates that, under ideal conditions, soybeans in southern Minnesota should be planted at about 140,000 live seeds per acre (see Table 1). Soybeans grown in central and northwestern Minnesota require harvest stands of approximately 125,000 to 150,000 plants per acre to maximize yields. This is likely due to shorter-statured soybeans with fewer total nodes that are often produced in these regions. Increased seeding rates are required in central and northwestern Minnesota.

Table 1
Maturity group II soybeans 140,000 live seeds per acre
Maturity group I soybeans 150,000 live seeds per acre
Maturity group 0 soybeans 160,000 live seeds per acre
Maturity group 00 soybeans 170,000 live seeds per acre

Planting date and soybean yield

Since early-May plantings usually result in maximum yields, lower yields should be expected for later plantings (see Table 2). Planting soybeans in Minnesota on May 10 results in only a 2-percent yield loss; on May 15 in a 3-percent yield loss, and on May 20 in a 6-percent yield loss (or 94 percent of normal yield).

Table 2
Planting date Yield loss (%) Yield potential (%)
May 1 0 100
May 5 1 99
May 10 2 98
May 15 3 97
May 20 6 94
May 25 9 91
May 30 13 87
June 4 18 82
June 9 24 76
June 14 30 70

For more educational information and tools, visit, a cooperative effort among the University of Minnesota, University of Minnesota Extension, and the Minnesota Soybean Research and Promotion Council. More information about delayed crop planting can be found at

By Jeff Stachler, Jeff Gunsolus and Rich Zollinger

Waterhemp is an annual weed species in the pigweed family that is capable of producing greater than 1 million seeds per plant and due to a limited number of effective herbicides, especially in sugarbeet and soybean, is difficult to control compared to most weed species.  In addition to the production of large quantities of seeds, continual germination throughout the growing season and an increased frequency of herbicide-resistant biotypes adds to the degree of difficulty in keeping this weed species under control.  The good news is that the longevity of waterhemp seeds in the seedbank is relatively short compared to most species (1 to 12% survival after 4 years), meaning complete control (zero seed production) of all plants over a three to four year time period should significantly reduce the waterhemp seed bank densities, allowing the farmer to take control of this difficult weed problem.

Winter Wheat Stand Evaluation

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It's time to determine whether the winter wheat came through the winter well enough to keep the stand. The best way to do this is to do a stand count. To do a stand count, use one of the following two methods:

1) Count the number of plants in a foot of row at several locations in the field. Take an average and convert in plants per acre using Table 1.

2) Take a hula-hoop, let it fall, and count the number of plants inside the hoop. Repeat this at random several times across the field and calculate an average. Use Table 2 to convert the count to an approximate population per square foot or acre.

Table 1 Stand Count Wheat JJW.jpg
Table 1. Average number of plants per foot of row for different row spacing and plant densities per acre.

Table 2 Stand Count Wheat JJW.jpg
Table 2. Adjustment factors to multiply the number of plants inside a hoop and convert the number in to number of plants per acre.

If your winter wheat hasn't started greening up again, you may be wondering if your winter wheat crop survived. To evaluate whether your winter wheat survived, I suggest you do the following: dig up several seedlings across the field and cut them longitudinal (lengthwise) with a very sharp knife or a safety razor blade. If the crowns look white/yellow to light green, they are healthy and will continue to grow. If you find that the crown has turned tan to brown and soft, it did not survive the cold weather.

In addition, you can check whether seedlings will grow by trimming the roots and leaves down to about ¼ to ½ " above and below the crown. Place these seedlings on a wet paper towel and place the towel in a Ziploc bag or plastic container that can be sealed. Place the container at room temperature and check for re-growth in 24-48 hours. Viable seedlings will show re-growth almost immediately (Photo 1). It will take longer than usual, but as long as the crown is healthy, a stand will establish and your field of winter wheat may not need to be destroyed.

Photo 1 Stand Count Wheat JJW (2).png
Photo 1 Regrowth of young winter wheat seedlings after 36 hours incubation in a Ziploc bag at room temperature (photo courtesy of Blake Vandervorst)

If stands across the fields average 15-17 plants/ ft2 or more you can leave the stand and expect near maximum grain yields. Often winterkill is not evenly distributed across a field but rather patchy. Smaller patches with stands as low as 8 plant / ft2 are probably worth saving. Weed control will be more troublesome with thin stands and the crop's growth will be variable making management decisions such as the correct timing of a fungicide application more difficult. If the patches with complete winter kill are larger than a couple if square feet and cover more than 20% of an area, such as in a ditch or on a knoll you may still want to consider replanting that area of the field to something else.

Sauk Centre Hay Auction Report April 2011

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By Dan Martens, Extension Educator, Stearns-Benton-Morrison Counties
I am posting information here for the April 7 and 21 Sauk Centre Hay Auctions. This includes:
SC Hay Auction 04 07 2011.pdf  A list of all tested hay lots and bedding materials sold... grouped by kind of hay, 25 RFV points ... cost per pound of dry matter and per RFV point.
SC Hay Auction 04 21 2011.pdf Same as previous
History of Selected Lots 2010 2011.pdf A summary of auction held this year: Medium Square Alfalfa in 25 RF points showing average and range for price and RFV.
Graphs of Med Sq Alf 2001 to 2011.PDF   A line graph of auction seasons from 2001 to 2011. The bold red line is this years season. A dash line indicates information not available.
Read more about plans for Alfalfa Scissors Cut Sampling in Central Minnesota for 2011
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