The WSMB Free Soybean Cyst Nematode Testing Program is Back in 2020!

Ann MacGuidwin, Damon Smith and Shawn P. Conley

The WI Soybean Marketing Board (WSMB) sponsors free nematode testing to help producers stay ahead of the most important nematode pest of soybean, the soybean cyst nematode (SCN). Eggs of SCN persist in the soil between soybean crops so a sample can be submitted any time that is convenient. The soil test report indicates the number of eggs in the sample and is useful for selecting the right variety for the next soybean crop. Retests of fields planted with SCN-resistant varieties over multiple years shows how the nematode population is responding to variety resistance and provides an early warning should the nematode population adapt to host genetics.

In the spring of 2012, the WSMB expanded the nematode testing program to include other pest nematodes in addition to SCN. These nematodes are less damaging to soybean than SCN but can cause enough yield loss to warrant treatment. As is the case for SCN, there are no rescue treatments for nematodes so the primary purpose of this year’s soil test is to plan for next year’s crop. Soil samples collected in corn for nematode analysis have predictive value for explaining yield if they are collected before the corn V6 growth stage. Sampling early in the season will provide information about the risk potential for the current corn crop AND the next soybean crop.

The assays used to recover nematode pests other than SCN in soil require that the nematodes are alive. So, it is important to keep the samples moist and at least room temperature cool. Collecting a sample that includes multiple cores ensures that there will be plenty of root pieces to assay. It is not necessary to include live plants in the sample. The soil test report will indicate which pest nematodes are present and at what quantities and their damage potential to soybean and corn based on the numbers recovered.

For more information on SCN testing and management practices or to request a free soil sample test kits please contact: Jillene Fisch at ( or at 608-262-1390.

Click to view more information on our WI SCN testing program or visit The SCN Coalition.

Remember the first step in fixing a nematode problem is to know if you have one! The WSMB sponsored nematode testing program provides you that opportunity. So Wisconsin farmers….”What’s you number?”

Just the Facts Jack: Soybean Planting Date, Seeding Rate and Seed Treatment Recommendations

When I am asked a direct question from a farmer or a crop consultant my response is always as follows…Do you want the short answer or the long answer as I can say the same thing in 5 minutes or 5 hours. Their response to me is almost always the same…”Just the Facts Jack”. In this blog I will attempt to answer three very agronomically important and challenging questions in a very succinct manner.  However as we all know brevity can be a gift or a curse depending upon the context of the question. With that being said here we go!

Question #1. When should I start planting soybean? My general response is to start planting your soybean crop ~7 to 10 days before you start putting your corn in the ground with the caveat that the soil is fit and you are following your crop insurance replant dates (However…IMHO, Jim Specht acronym,: I do believe that RMA needs to revisit these dates for Northern soybean growers). We have measured soybean yield loss due to delayed planting date as early as ~April 25th however the rapid yield decline (up to 0.5+ bpa per day) occurs at ~May 10th. As you would expect the magnitude of this planting date yield response is soil and climate dependent and yield losses in some areas (TED’s) where as high as 2.8 bpa per week for delayed planting (Figures 1 and 2). For a deeper dig please review the below supplemental documents.


Figure 1. Map of the North Central US region showing nine technology extrapolation domains (TEDs) used in this analysis.

Figure 2. Producer soybean yield plotted against planting date in 9 technology extrapolation domains (TED) in the NC USA region.

Question #2. What is the optimal soybean seeding rate? The quest for the optimal agronomic soybean seeding rate for yield vs. the optimal economic seeding rate has been an ongoing debate. Fortunately a large group of academics and industry (thank you Corteva) were able to combine data sets and address this question (Figure 3). Our results suggest that for “on-time” soybean planting dates the optimal agronomic soybean seeding rate to achieve 99% yield potential ranged from 237,000 to 128,000 seeds per acre (assuming 90% germ) across environments; whereas the optimal economic soybean seeding rate ranged from 157,000 to 103,000 seeds per acre. Thankfully this roughly confirms my original recommendation that you buy a bag an acre (140K) and place ~20% more seed on the low yielding acres and ~20% less on the high yielding acres. If planting is delayed however we do recommend that you increase your seeding rate accordingly (Adjust Your Seeding Rate (Higher) But Not Your Maturity Group For Late May Planted Soybean ). For a deeper dig please review the below supplemental document.

 Location of 211 trial site-years that are included in the database and their respective environmental cluster classifications.

Figure 3. Location of 211 trial site-years that are included in the database and their respective environmental cluster classifications.

Table 1. Agronomic and Economic Optimal Soybean Seeding Rates by Environmental Cluster.

Cluster 1

Cluster 2

Cluster 3

Yield level (bu a-1)

Agronomic/(Economic) Optimal Seeding Rate1,2

< 58




58 – 71




> 72




1Agronomic optimal seeding rate (x1000 seeds) based on 99% maximum yield level.

2Economic analysis based on $62 a unit (140k) for seed and $9 a bushel pricing; soybean price and seed cost fluctuations will change the EOSR.

Question #3. When do I use a soybean seed treatment? I purposely placed this questions last as I know it will draw significant ire; however the data are what they are. Soybean seed treatments should only be used in some early planted soybean situations and/or if you have a history of or have scouted for an insect (i.e. Bean leaf beetle) or a pathogen (i.e. SDS) that exceeds economic thresholds. For a deeper dig please review the below supplemental document.

Th-th-th-that’s all folks!

Winners of the 2019 WI Soybean Yield Contest are Announced

The 1st place winner in Division 4, RnK DeVoe Farms of Monroe, grew Pioneer P28A42X and harvested 91.08 bu/a.  In second place, Venable Farms Inc. of Janesville grew Jung 1213R2X and harvested 87.48 bu/a.  In Division 3, Jim Salentine of Luxemburg harvested 92.44 bu/a with Stine 19BA23 and in 2nd place, Tim Gaffron of Twin Lakes harvested 89.13 bu/a with Pioneer P24A80X.  In Division 2, Wegner Farms of Sparta achieved 75.63 bu/a from Pioneer P23A15X for first place.  In 2nd place, David Lundgren of Amery harvested 64.13 bu/a from Asgrow AG11X8 soybeans.  No entries were submitted for Division 1.

RnK DeVoe Farms of Monroe was the winner of the Soybean Quality contest with 2,967 pounds of protein (34.9%) plus oil (19.4%) per acre from Pioneer P28A42X.

The contest is sponsored by the WI Soybean Program and organized to encourage the development of new and innovative management practices and to show the importance of using sound cultural practices in WI soybean production.

For more information please contact Shawn Conley, WI State Soybean Specialist at 608-800-7056 or

Finalists for the 2019 WI Soybean Yield Contest are Announced

The 2019 season had below average growing conditions for many growers.  We experienced lower entry numbers in the 2019 WSA/WSMB Soybean Yield Contest, likely due to delayed planting and harvest from wet weather causing maturity, time and logistic struggles.  The top two entries in each division (in no particular order) were:

Division 4:

  • Rick DeVoe, Monroe (planted Pioneer P28A42X)
  • Nick Venable, Janesville (planted Jung 1213R2X)

Division 3:

  • Tim Gaffron, Twin Lakes (planted Pioneer P24A80X)
  • Jim Salentine, Luxemburg (planted Stine 19BA23)

Division 2:

  • David Lundgren, Amery (planted Asgrow AG11X8)
  • Mike and Dean Wegner, Sparta (planted Pioneer P23A15X)

Division 1: 

*No entries were submitted for Division 1

The Soybean Quality Contest was optional for any Soybean Yield Contest entrant.  There are no geographical divisions for the Quality Contest.  One cash award will be presented statewide to the highest protein plus oil yield per acre (measured in lbs. per acre). The finalists for the Soybean Quality Contest are:

  • Rick DeVoe, Monroe (planted Pioneer P28A42X)
  • Jim Salentine, Luxemburg (planted Stine 19BA23)

The final ranking and awards will be presented at the Corn Soy Expo to be held at the Kalahari Convention Center, Wisconsin Dells on Thursday February 6th during the WSA/WSMB annual meeting.

The contest is sponsored by the WI Soybean Program and organized to encourage the development of new and innovative management practices and to show the importance of using sound cultural practices in WI soybean production.

For more information please contact Shawn Conley, WI State Soybean Specialist at 608-800-7056 or

Dealing with Wet Frozen Soybeans

Like many farmers the UW BeanTeam still has soybean sitting in the field. Both locations (FDL and East Troy) have not been fit to run since maturity and FDL had 7 inches of snow piled on top of standing water yesterday. Anyway…. once fields freeze and we can get back after the crop, here are a few things to consider. Check back as this information will likely be updated as I glean more information and receive audience feedback. This information is provided in greater detail in the below two excellent resources.

  1. Call and mail (i.e. paper trail) your crop insurance agent to let them know you may not be able to get the crop out before the deadline.
  2. Take what you can get this fall. Soybean does not “store” well in the field over the winter. Shatter and seed quality degradation may lead to an unmarketable crop if taken in the spring.
  3. Set the combine and check it often if you are running snow through the housing. The cold temperatures may be to our advantage as the snow should move easier.
  4. Header shatter will be an issue. Make sure you set the combine to manage flow. Remember for every 4 seeds per square foot on the ground that equates to roughly a bushel in yield loss.
  5. Double check your combine moisture with another device to verify correct moisture as this cold weather will wreak havoc with sensors. We pulled beans today and they were 16.4%.
  6. Call ahead and around. Verify what the elevators will take in terms of moisture content. Furthermore some elevators are assigning a wet bin to assist farmers in harvest.
  7. Do not harvest and store wet beans on farm. I have heard some coffee shop talk about cutting and “freeze blasting the soybean seed”. This is a bad idea.
  8. Don’t use too much heat. It appears that 100F is about the right temperature to minimize splits.

Drying and storing wet soybeans

Harvesting and storing soybeans

Updates from Brian Luck regarding combine settings:

Harvesting soybeans later than intended can present many challenges for minimizing harvest losses. These challenges are amplified when snow is on the ground and impacting harvest. Minimization of losses starts at the header. Checking that the sickle bar knives are sharp and the guards are adjusted properly will ensure the stems are being cut rather than broken or leaned over by the header. Generally, reel speed should be slightly faster than grounds speed to make certain the plants are being collected by the header. Another good practice for harvesting soybeans in wet and snow covered conditions is to reduce the combine ground speed while harvesting. This will give the machine extra time to cut the plants and ensure that they are transported to the throat of the machine with minimal damage or losses.

Concave clearances, rotor speeds, fan speeds, and sieve settings all depend on the condition of the crop at harvest. If the beans are generally dry but the stems, pods, and remaining leaves have increased moisture contents more aggressive threshing may be required to clean the plant material from the crop. More aggressive threshing can also lead to damage and reduced crop quality. Incremental adjustments of concave clearances (increase for wet conditions) then threshing rotor speed (increase for wet conditions) will help to find the optimal settings. Also, ensure that you have a uniform feed rate into the machine maintaining a consistent load on the threshing rotor to ensure optimal performance. Finally, increased fan speed can help pneumatically separate the soybeans from the plant material, however this can also lead to greater losses through the sieves if set too high.

Small adjustments to these combine settings can have a big impact on the performance of the machine. Check for losses behind the combine often to make certain that your harvest is as efficient as it can be in adverse conditions. Try to identify where losses are happening when operating the machine. If you can see beans leaving the header focus on minimizing that loss before making any other adjustments. Incorrect settings at multiple stages in the combine can significantly increase losses and will be difficult to identify.


Harvest Considerations for Variable Soybean Maturity

Variable soil types, knolls, flooding and ponding, variable planting dates and random pest pressure have left many growers with extreme (worst I have ever seen) in-field variability of soybean maturity in 2019.   There are areas in fields where the soybean seed is approaching maturity adjacent to areas with green seed.  The prevailing question is “When should the grower harvest?” Obviously there is no simple answer, as each field is different. However here are a set of guidelines to consider:
1.    The easiest answer is harvest the field at two different times. Take what is dry today and come back in two weeks and harvest the rest. The challenge with this approach is that today’s equipment is large and not easily moved from field to field. Furthermore many growers rent or own land over large areas where this is impractical and the whole field must be taken at once. So……
2.     The next simple answer is wait until the whole field is ready to go. As noted in a past article entitled Drought Induced Shatter, we are seeing areas across the Midwest where shattering is occurring. The general rule of thumb is 4 seeds per square foot = one bushel yield loss. At local cash prices hovering near $8.00 per bushel this is hard to see happen and not harvest. Furthermore, waiting will also lead to moisture loss in the field. As we learned the past few years, you do not get compensated for harvesting below 13% moisture. So…..
3.     If growers are concerned with shatter and/or other harvest losses the next logical approach is harvest ASAP. This opens a whole new can of worms. Harvesting ASAP will lead to a mixture of dry, wet, and immature (green) soybean seed. Be aware that if you harvest this mixture regardless of the ratio, your combine moisture sensor may not detect the correct moisture, be prepared for that initial shock when the elevator tests the grain. Next be prepared for the dockage. Most combines will leave more beans in the pod when they are wet or immature.   These beans may end up on the ground or in the grain tank as unthreshed soybeans. Harvesting seed with this variability will be very similar to handling frosted soybean seed so discounts may occur due to moisture shrink, damage (green beans are considered damage), foreign material (this is usually higher when harvesting wet beans), test weight, and heating. If you choose on farm storage to address some of the dockage concerns please refer to Soybean Drying and Storage for questions.
4.  The last consideration I would bring forward is that the mature areas are likely going to be the low yielding pockets due to early senescence whereas the yet to mature areas will likely be the higher yielding areas within the field. So, in short, which yield environment would you rather focus your time and efforts to protect?       
The question ultimately comes down to the bottom line and where you make the most $$$. If shatter is not occurring and you have good equipment that does not incur significant harvest loss, will harvesting grain that is over-dry make you more money than harvesting seed that may incur significant dockage? My guess is yes but you tell me!
Image 1. Variable Maturity (M. Rankin)

High Value Straw and Weedy Wheat…What Do I Do?

Wet fields, thin stands and spotty winter-kill made spring weed control difficult to impossible in many winter wheat fields, and prolonged wet conditions have encouraged prolific weed growth from competitive broadleaf weeds like giant ragweed and lambsquarters. As we approach harvest in southern WI (week of July 21st) growers simply have limited herbicide options for preharvest weed management. The most popular ones are:

  1. 2,4-D products. There is a 14 day pre-harvest interval with this product. Pre-harvest treatment can be applied when grain is in the dough stage. Only one preharvest application per crop cycle allowed and a maximum of 0.5 lb 2,4-D acid equivalent per acre per application. Please read label for specific product used as there are differences among labels.
  2. Glyphosate products. There is also a 7 day pre-harvest interval with this product, and it can NOT be applied until the grain is at the hard-dough stage (30% moisture or less). Grain treated with glyphosate at this growth stage should not be used for seed as germination can be significantly lowered. Maximum of 0.77 lb glyphosate acid equivalent per acre per application (equivalent of 22 fl oz of Roundup PowerMax per acre).

Some benefits to applying preharvest 2,4-d or glyphosate may include desiccation of green weedy plants to enable an easier combine harvest and quicken the ability to bale straw following the grain harvest. However, drawbacks include a narrow window of application timing ahead of harvest, wheel tracks (if ground applied) will reduce grain yields, and moreover many of the weeds like giant ragweed, waterhemp and lambsquarters will be large and difficult to control. Drift is also a concern when spraying crops this late in the season, particularly with synthetic auxin herbicides such as 2,4-D. Thus, consider a preharvest 2,4-d or glyphosate application as a last resource because partial control of large weeds will greatly increase selection pressure for herbicide resistance. We already have several issues of herbicide resistance in Wisconsin (

Shawn P Conley and Rodrigo Werle

A Tank Full of Sugar Helps the Profits Go Down

Adapted from original article written 6/1/2015.

This growing season has been what I can best describe as “Craptacular“. Farmers are under severe economic stress and are looking to squeeze the highest yields possible out of whatever acres they were able to get planted. Across the Midwest post emergence herbicide applications are going out and farmers are considering what else to add into the tank to “help” their crops. This year the question of sugar has resurfaced so I thought I would dust off and re-post the below article originally entitled “Do Foliar Applications of Sugar Improve Soybean Yield”.

I also wanted to link to a few other articles from colleagues at the University of Nebraska “Sugar Applications to Crops – Nebraska On-Farm Research Network Results” and “Research Results: Sugar Applications to Crops“. In short the University of Nebraska team did not find a consistent yield increase in corn or sorghum and averaged 0.8 bu per acre in soybean. If farmers are considering a pass for just the sugar application the average cost of ground application in $7.65 and aerial is $10.75; 2019 Iowa Farm Custom Rate Survey and the average yield loss caused by sprayer wheel track damage in soybean in rows less than 20 inches is 1.9 or 1.3% with a 90 or 120 foot boom, respectively.

I also want to give credit to my colleague Chad Lee who wrote a nice article entitled “Could Sugar Help Drought Stressed Corn?” that discusses sugar rates, biological activity and actual costs of product.

I am certain this re-posted article will stir up the same severe indignation as the original, however when the local cash bids are averaging $8.42 ROI is more important than ever.

Do Foliar Applications of Sugar Improve Soybean Yield (Originally published: June 14th, 2011)

High commodity prices have led growers to consider many novel soybean inputs. One input that has garnered considerable attention is the foliar application of sugar products to increase soybean yield. The objective of this research was to evaluate soybean yield in response to various sources of foliar-applied sugar across four states in the Midwest. Field research studies were conducted at Arlington, Wisconsin; Urbana, Illinois; St. Paul, Minnesota; and West Lafayette, Indiana in 2010.The four sources of sugar evaluated in this study were:

  1. Granulated cane sugar
  2. High fructose corn syrup
  3. Molasses
  4. Blackstrap molasses.

All treatments were applied at the equivalent rate of 3 lb sugar a-1 and applied at 15 to 20 gal a-1. The treatments consisted of an untreated check, all four sources of sugar applied at V4, granulated cane sugar and blackstrap molasses applied at R1, granulated cane sugar applied at V4 and R1, and blackstrap molasses applied at V4 and R1.

No positive or negative (phytotoxic) effects were visually observed on the soybean foliage at any location within 10 days following foliar applications (data not shown). Furthermore, sugar did not increase soybean yield within location (data no shown) or across locations [P= 0.60 (Figure 1)], regardless of source. While this study cannot conclusively prove foliar applications of sugar will not increase soybean yield, the authors conclude that other management strategies to improve soybean yield should take precedence over applying sugar.


The source of this data is:

Furseth, B. J., Davis, V., Naeve, S., Casteel, S., and Conley, S. P. 2011. Soybean Seed Yield Was Not Influenced by Foliar Applications of Sugar. Crop Management. Accepted: 6/1/11.

Please visit: to view the entire manuscript.

Soybean and Corn are Considered Cover Crop Options in WI

Article written by Shawn P. Conley, Joe Lauer and Paul Mitchell

Today Joe Lauer and myself had the opportunity to travel to Door County and participate in an Extension meeting hosted by Annie Deutsch, Jamie Patton and Aerica Bjurstrom. We had great conversation with the group about the agronomic implications of the 2019 growing season. During this meeting we touched on the issues regarding prevent plant and what to do next. This is a obviously a complex issue but an interesting point was brought forward by Dan Muhlenbeck a crop insurance specialist… “Is soybean and/or corn considered a cover crop in WI?”  (I hope you all notice that in my blogs soybean always precedes corn..) Here are our thoughts.

For a crop to be considered a cover crop RMA states that “For crop insurance purposes, a cover crop is a crop generally recognized by agricultural experts as agronomically sound for the area for erosion control or other purposes related to conservation or soil improvement.” Soybean and corn both meet this requirement. However please remember that BMP’s must be followed to meet this requirement.

In a late planted, soybean cover crop situation, plant a minimum of 150,000 seeds per acre and strive to plant in narrow row spacings (<30 inches). This recommendation is intended to minimize soil erosion, maximize ground cover and weed suppression as well as provide adequate N fixation. I do however understand if a farm operation is limited by equipment restrictions (e.g. they only have a 30 inch row planter) I would not preclude them from being eligible to plant soybean as a cover crop. The next consideration is cost. Normally the cost of soybean seed to be used as a cover crop on a per acre basis would be cost prohibitive; however since soybean seed is usually not saved from year to year and treated seed is often devitalized it is often offered at a deep discount late in the year so shop around. Frankly with only 60% of the WI crop planted there should be some reasonably priced seed to be used as cover crops.Now lets talk about corn!

Although corn is not usually considered a cover crop due to 30-inch row spacing and slower early canopy growth than other crops, it is deep-rooted and by the end of the end of the growing season can produce more than 5 Tons DM/A of stover even when planted in July. Ultimately the decision to use corn as a cover crop is the cost of production. Typically, it would cost $400 to $450 per acre to establish corn. Production costs can be reduced by using seed that is not bioengineered, reducing N fertilizer to around 40 to 60 lb N/A, and using a narrower row corn planter (<30-inches), a twin-row planter, or grain drill to narrow row-spacing.

To be clear the intent of this article is to designate that soybean or corn can be considered as options for cover crops. The first thing you must do however is talk to your crop insurance agent and make no decisions without their input. Also please review this excellent article by Paul Mitchell entitled: Can I Use Corn or Soybeans as a Cover Crop on Prevented Plant Acres?

Farmers taking the full prevented plant indemnity should note that they cannot ever harvest the cover crop for grain or seed. RMA rules allow, only after September 1, grazing and harvest as hay (for bedding or feed) and now for silage, haylage or baleage. If a farmer wants to harvest it as grain or seed, then they should declare it as an alternative crop and only collected the partial (35%) prevented plant indemnity.”

With the aforementioned change to prevent plant indemnity the question of soybean as a forage popped into my mailbox multiple times today. From an agronomic perspective I think there are better forage options (higher tonnage) than soybean, but if this is an option for your farm here are some simple thoughts. Harvesting soybeans for forage between the R1 and R5 stage will result in a very high quality silage, but dry matter yields will be reduced significantly. Forage quality will be reduced from R5 soybean forward if a conditioning process is used during harvest as conditioning will cause significant seed shattering. According to our data early maturity group soybeans planted 6/20ish will likely already be at the R6/R7 stage so if you are intending to shoot for higher quality soybean forage go with a later maturity group soybean (~4.0).

Figure 1. Pooled Arlington and Hancock Data.

Figure 2. Spooner data.


This is a dynamic discussion so please check back as text and recommendations are subject to change as “to be frank” no one really has all the answers on this topic.