Crappy Prices Followed by Crappy Harvest Weather…These Beans Better Not Sprout Too!

The weather outlook does not look promising for any soybeans getting harvested over the next few weeks. This reality has many growers concerned about soybean sprouting in the pod. Fortunately this is not a common concern for northern soybean farmers but may be a problem in 2018. Given my lack of experience on this topic I leaned on a few of my southern colleagues for thoughts and advice on this topic.

Dr. Jeremy Ross; Extension Agronomist – Soybean/Professor ; Crop, Soil, and Environmental Sciences Department; University of Arkansas System Division of Agriculture stated:

We’re having issues with this again this year.  From my observation, this tends to be a bigger problem in years where we have adverse weather conditions (typically hot and dry) during early reproduction, and then we have wetter than normal conditions during late reproduction.  This is what we saw in 2009, 2016, and this year.  My thoughts are that the pod cannot expand as rapidly as the seed expands, rupturing the pod suture.  Once exposed to moisture, these seed sprout.  I have seen seed sprout prior to the pod rupturing, and I can’t explain that sprouting other than excessive moisture caused the sprouting.  Usually it’s just a few pods that show this, and they are usually at the same position on the main stem (all the pods developed at the same time).  I’ve seen this happen up and down the main stem, but usually in the upper ½ of the plant is where I see the occur most frequently.  From what I have seen in the past, the affected pods are less than 5% of the total number per plant.  I haven’t  seen this specific to any one particular genetics, variety or company. For more information refer to his blog article entitled: Splitting pods and sprouting soybean seed in the pods

Dr. William Wiebold, Professor of Agronomy in the Division of Plant Science at the University of Missouri provides very detailed and excellent information regarding the mechanisms of sprouting in soybean in this article entitled: Wet Weather Can Cause Seeds to Sprout on the Plant.

Lets just hope the weather forecast is wrong and WI soybean farmers start rolling in their soybean fields like Bucky will roll over Nebraska this Saturday! Go Bucky!!!

Drought Stricken Soybeans..Should I Leave Them or Take Them for Forage?

Late soybean plantings followed by dry conditions have some northern WI growers considering chopping their soybean as a forage. Before you even consider this option make sure you check the label of the pesticides applied to the crop before you grease the chopper.

  • Let’s start with the herbicides first. In short, outside of glyphosate (25 day) and a handful of pre’s and posts (please refer to Table 3-3 in A3646, Pest Management is WI Field Crops) most soybean herbicides are listed as “not permitted” for forage use.
  • Next, many common insecticides used for soybean aphid management implicitly state “Do NOT graze or feed treated forage or straw to livestock” (please refer to A3646, Pest Management is WI Field Crops) .
  • Lastly, fungicide labels are as equally exclusive with pre-harvest intervals ranging from 14 days to “Do NOT graze or feed soybean forage or hay” (please refer to A3646, Pest Management is WI Field Crops) .

If you somehow pass the gauntlet of “Do not” or “Not Permitted” and the forage value is greater than the grain value then the highest protein and yields are obtained from soybean harvested at the R6 to R7 growth stage. 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.

Here are some options for you to consider to help think through the forage versus grain decision.

Option # 1: Soybean haylage considerations

  • What is my realistic tonnage expectations?
    • Late planted drought stricken soybean will yield ~1 to 2 tons of dry matter per acre.
  • What is it going to cost me to harvest and put this crop up?
      • Mowing ($14.20 per acre)
      • Swathing ($7.75 per acre)
      • Haylage (Chopping, hauling, & packing bunker; $49.20 per acre)
  • How should I price this crop?
    • If you were to price the soybean forage based on expected grain yield and CBOT then realistic yield levels would range from 15 – 25 bu per acre at $7.95 per bu (local cash price: 8/22/18). Expected forage value range would be $119.25 to $198.75 per acre.

Option #2: Green manure considerations

  • I am tired of throwing money at this crop……….
    • Though you will save on harvest costs the average cost of a plow down disk operation is $19.70 per acre.
  • How much will I save on next years fertilizer bill?
    • By not harvesting the crop you will not remove the 30# P and 85# K (estimated removal rates of P2O5 and K2O for 15-25 bu per acre soybean grain and straw (A2809)).
    • You may contribute 20-40 pounds of N to next years corn or wheat crop.

Neither of these prove to be particularly attractive options. However I would encourage growers, crop consultants, and nutritionists to weigh the true economical value of each option carefully before proceeding.

I swear to tell the truth, the whole truth and nothing but the truth

Shawn P. Conley, University of Wisconsin-Madison and Jeremy Ross, University of Arkansas System Division of Agriculture

For many of us in agriculture, 2017 was a year we would like to quickly forget. Unpredictable weather, low crop prices and last, but certainly not least, many of us were dealing with the D-word, and I don’t mean Dallas. Off-target movement of synthetic auxin herbicides pitted neighbor against neighbor, farmers against state boards and industry against academia. The caustic environment in agriculture in 2017 made the politics in Washington D.C. look like Sesame Street!

On October 30th 2017 Dr. Kevin Bradley published A Final Report on Dicamba-injured Soybean Acres where he listed an official count of 2,708 reported cases of dicamba-related investigations and an estimated 3.6 million acres of dicamba injured soybean. The efforts of Dr. Bradley as well as many other Extension Weed Scientists led to wholesale changes in herbicide labels and mandatory training prior to the 2018 growing season. The collective hope was to keep these herbicides on-site, where we put them!

This spring, Mother Nature gave many growers across the Midwest small windows to plant soybean in April and early May. Planters got ahead of spray rigs, pre-emergent herbicides didn’t get out and boom, we are behind the 8-ball for weed control options. Those early planted soybean acres then decided to bloom in June which put applicators and farmers against the clock to get their post emergence herbicides on according to label. In the Midwest, it has rained for the past week and applicators have been challenged again to get into the field.  Later planted soybeans will start to bloom over the next week and again put applicators and farmers running against the clock to get their post emergent herbicides on consistent with label directions.  If dicamba was applied post emergence, we can simply mark our calendar forward 14-21 days, cross our fingers and hope that the label changes, applicator training, and more recognition of the potential problems worked and we don’t see any off-site injury.

Let’s fast forward to now. The first official unoffical report of crop damage due to dicamba injury was reported by Dr.  Bradley today “Dicamba Injured Crops and Plants Becoming More Evident: June 15th Update”. We are also starting to see images and early reports of dicamba injury coming from the Mid-South and lower mid-western states. It would be irresponsible to make any wide sweeping claims of pending doom; however, if it does show up it would be even more irresponsible to not report it.

I have been told by many colleagues in both academia and industry that farmers across the country are gun shy to report any damage this season. The three main reasons given by growers are:

  1. I am in a drought stricken area and if I report any damage I will be ineligible for crop insurance!
  2. This is my neighbor, we are friends and I don’t want the government involved. We can handle this between us.
  3. We need this technology and I don’t want to lose it!

As a farm kid myself, I fully understand all of the reasons mentioned above. However, we must all be cognizant that just because we don’t report a problem doesn’t make it go away. There are far too many recent examples of institutional non-reporting that have come back to severely damage the reputation of the non-reporting entity (MSU, Face Book, #MeToo, etc.). Our institution is agriculture! We battle misinformation on GMO’s, we battle misinformation on animal husbandry, and we constantly battle educating the other 99% on what we do. If 2018 turns out like 2017 we do not want to stick our heads in the sand and pretend a problem does not exit. If 2018 turns out to have minimal issues then FANTASTIC! Industry and academia should be lauded for their joint accomplishments. The best way to support agriculture and freedom to operate is through honesty and accurate self-reporting.

Are Your Beans “Feelin the Burn”?

Shawn P. Conley and Damon Smith

Weed management has been a significant challenge for many farmers and retailers in 2018. The challenges range from short planting windows to shorter pre-emergence and post emergence herbicide application windows to early soybean flowering. As we approach the end of growth stage cutoffs for herbicide applications in soybean can we expect any damage from herbicides and especially the Group 14 herbicides? Well unfortunately the answer to that question is the good ole Extension cop-out answer “Well folks that depends“…..

What we mean by that is as follows:

  1. What growth stage was the soybean crop at?
  2. Where in the United States are you located?
  3. Was the crop stressed before or more importantly after the application?
  4. What rate, a.i., adjuvants, carriers, tank mix partner, etc are we dealing with?
  5. What soybean variety did you plant?
  6. What phase is the moon in….well not really… but you all get the point.

Generally speaking as the soybean growth stage approaches R1 (flowering) the risk for yield loss increases. However this is a highly regional response as we have documented differential yield responses from a +1.2% yield gain in the south to a -4.7% to -4.1% yield loss from the I-states north (Table 1). Furthermore as we transition from specifically using lactofen as a “herbicide” to a tool in white mold management we also note a differential response.  In a recent meta-analysis where Dr. Smith focused on the 6 oz lactofen rate at R1 application he noted a 3.7% yield loss in low-to-moderate disease pressure, but a significant yield increase in high-pressure situations (Figure 1). In Dr. Smith’s meta-anlaysis he does want to emphasize they noticed A LOT of variability among varieties and environments tested  as you can see by the error bars around treatments in Figure 1.

In summary we would expect some level of yield loss in these late “hot” applications; however in-terms of long-term weed management we would rather see you take a small yield hit than allow herbicide resistant weeds go back to seed and replenish the weed seed bank. This is even more critical with potential Chinese tariffs and tighter phytosanitory regulations centered around weed seeds.

Table 1. Percent relative yield change and break-even probabilities for Lactofen applications (12 fl. oz per a + 1%v/v COC) at V4 soybean compared to no application at multiple yield levels and soybean sale prices for studies be­tween 2012 and 2014.


Yield level


45 bu a-1

60 bu a-1

75 bu a-1

Region RYC (%)










——————-% probability of break-even——————-
























-4.1 0 0 0 0 0 0 0 0


†RYC, percent relative yield change compared to the standard practice
South: Arkansas, Kansas, Kentucky

I-States: Indiana, Iowa, Illinois

North: Michigan, Minnesota, Wisconsin

Figure 1. Yield response to white mold management by disease pressure.

Literature cited:

J.M. Orlowski, B.J. Haverkamp, R.G. Laurenz, D.A. Marburger, E.W. Wilson, S.N. Casteel, S.P. Conley, S.L. Naeve, E.D. Nafziger, K.L. Roozeboom, W.J. Ross, K.D. Thelen, and C.D. Lee. 2016. High-input soybean management systems affect soybean yield, yield components, and economic break-even probabilities. Crop Sci. 56: 4: 1988-2004. doi:10.2135/cropsci2015.10.0620.

Willbur, J., P. Mitchell, M. Fall, A. Byrne, S. Chapman, C. Floyd, C. Bradley, K. Ames, M. Chilvers, N. Kleczewski, D. Malvick, B. Mueller, D. Mueller, M. Kabbage, S.P. Conley, D.L. Smith. 2018.  Meta-analytic and economic approaches for evaluation of fungicide impact on Sclerotinia stem rot and soybean yield in the North Central U.S. PhytoPatholgy. In review

The Soybean Flowering – Summer Solstice Fallacy

Shawn P. Conley, Lindsay Chamberlain and James Specht

Every agronomist has been ingrained with the Nowledge that soybean is considered a “short-day” plant and will not flower until after June 21st a.k.a. the summer solstice. This belief has held true for decades; however, with agronomists now preaching the virtues of early soybean planting, coupled with the power of Twitter, we now see pictures and evidence of soybean flowers occurring as early as June 1. This empirical evidence has prompted many to question the foundational belief.

In soybean, floral induction occurs when soybean leaves can measure the night length (from dusk to dawn), and thus begins when unifoliolate leaflets appear at stem node 1 (V0) and a young trifoliolate leaf appears at node 2, with induction continuing thereafter in every subsequent leaf (Wilkerson et al. 1989; Fehr and Caviness, 1977). If soybean is planted early enough, flower initiation can then be triggered on the front of the summer solstice (Figure 1). This response is dependent upon the maturity genes present in the adapted cultivars and region of country, however given the germplasm available to farmers in the north central region it is plausible that any soybean planted in this region would flower “early” if planted early.

In 2018 we have experienced exceptionally warm temperatures after V1 that have significantly hastened the calendar date of R1, because the temperature sensitivity of floral evocation (development of floral meristems into flowers – the first such visible flower leading to an R1 stage call), though floral induction in itself is not very temperature sensitive.  In NE in 2017, the website program SoyWater (SoySim) predicted that an Apr 24 planting date would lead to the R1 stage dates for MGs 1, 2, 3, & 4 to occur on Jun 12, 14, 17, & 19; however, this year (2018), SoyWater (SoySim) is predicting for the same planting date of Apr 24 and near similar MGs, R1 stage dates of June 05, 10, 13, & 16!  Those R1 stage predictions were (as Dr. Specht recall) 3-5 days later a couple of weeks ago, so not only a warm spring, but also this exceptional heat wave in the last few days has hastened floral evocation.  R1 is likely to be earlier in all NC USA areas that have experienced both early soybean planting and a much warmer than normal spring. Early soybean flowering has many management implications including shorter herbicide label timings for dicamba (up to R2) and glyphosate products (through R2) (FYI it usually only takes 3-5 days to go from R1 to R2) and earlier risk for white mold infection. In 2018 it is paramount that you scout and don’t just rely on the calendar for spray applications!

Figure 1. Planting date by day length hours in Lincoln NE.

Literature cited:

Fehr, W.R., Caviness, C.E., 1977. Stages of soybean development. Cooperative Extension Service, Agriculture and Home Economics Experiment Station, Iowa State University, Ames, Iowa.

G, G. Wilkerson,* J. W. Jones, K. J. Boote, and G. S. Buol. 1989. Photoperiodically Sensitive Interval in Time to Flower of Soybean. Crop Sci. 29:721-726.

Variable Germination and Emergence in Soybean: Which Seeds Are Still Viable?

Many of us, including myself, have planted under less than ideal soil conditions this spring.  Often the ground was worked a little on the wet side leading to clods and variable seeding depths for our soybean crop.  Reports of variable and delayed emergence in conventional (more common) and no-till soybean is raising replant and seed viability questions in several areas across the Midwest.  If soybean was planted into dry soil and had not imbibed water (seed did not swell) then there is little to no concern for growers.  Once a significant rainfall event occurs, the soybean will imbibe water, germinate, and should emerge normally.  For yield estimates, we would assign the day it rained as the new planting date.

The more difficult question to answer is “How viable is the soybean seed once imbibition and/or germination has begun?”  The critical seed moisture content for soybean germination is 20%.  A soybean seed that has imbibed water, has a split seed coat, or has an emerged radicle will continue to germinate and grow as normal once the seed is re-hydrated if the seed (embryo) remains above 20% moisture (Senaratna and McKersie, 1983) (Image 1).

Image 1. Soybean germination

If the moisture content within a soybean seed falls to 10% due to dry conditions after germination has started, then a dramatic difference exists among the different seed germination stages.  If the seed has imbibed water for 6 hours (seed is swollen, but the seed coat has not broken), then the seed is dehydrated to 10% moisture, germination is not affected.  If the seed has imbibed water for 12 to 24 hours (seed coat broken, but prior to radicle emergence), then germination is reduced to 60 to 65%.  If the radicle has emerged and seed moisture levels drop to 10%, then no survivors can be expected (Image 2).

Image 2. Variation in soybean imbibition

To test seed viability, growers can conduct a simple germination test.  First excavate 100 soybean seeds and wrap them in a damp paper towel.  Place these seeds in a warm location, and after 24 to 36 hours, count the number of seeds that have germinated (Image 2).  Remember that a typical soybean germination is 90% (Image 3).

Image 3. Soybean germination roll test

Literature Cited:

Senaratna, T. and B. D. McKersie.  1983.  Dehydration Injury in Germinating Soybean (Glycine max L. Merr.) Seeds.  Plant Physiology 72: 620-624.

Adjust Your Seeding Rate But Not Your Maturity Group For Late May Planted Soybean

Authors: S.P.Conley, J.M Gaska, S. Mourtiznis, D. Mueller, A. Varenhorst

With only 10 days left in May and roughly 50% of the Midwestern soybean crop planted (WI:33%, IA:58%, SD:24%) what if any production changes should growers consider modifying?

  1. Do Not Switch Your Maturity Group….Yet: Do not consider switching to an earlier soybean maturity group until ~June 1. After June 1 do not go any earlier than a 0.5 MG earlier variety. For more information please see:  Soybean Planting Date and Maturity Group Considerations Moving into 2018
  2. Increase your seeding rate to roughly 154,000 seeds per acre. Efficacy of soybean seed-applied fungicide and insecticide at early and late planting dates and a range of seeding rates were tested in multiple states during the 2016 and 2017 growing seasons. Researchers in Iowa, South Dakota, and Wisconsin participated with 4 locations each year for a total of 24 location/years.  Seed treatments included a) UTC, b) fungicide (prothioconazole, penflufen, and metalaxyl), and c) fungicide+insecticide (clothianidin). Only late planting dates were used in this below analysis. The average of the late planting dates for each state over the two years were: IA: May 24,  SD: June 21, and WI: May 31.  Seeding rates were in increments of 20,000 from 60,000 to 160,000 seeds/acre. There was a quadratic yield response to seeding rate that was significant (Figure 1). Maximum yield was observed at 154,000 seeds/acre. The curve is not very steep which shows that practical yield differences between seeding rates were not large. So, the curve does not tell the whole story. We re-ran the model with seeding rate as a categorical variable. The results suggest that yields for 140 and 160K were not different and 100-140K were not different either (Table 1). It may be argued that our seeding rate was not extended high enough…I assume my Twitter “friends” will come back and say “hey bean boy why didn’t you go to 180 or 220,000 seeds per acre”. That is a valid critique however given the flat response curve we find it difficult to believe we would have seen a significant yield response above where we are. As a reminder our recommended seeding rate for early planted soybean can be found here: The Soybean Seeding Rate Conundrum.
  3. Interpret the return above seed cost cautiously. The best part of writing in a blog format is that you get to tweak the post after it is published. To that point we have had several comment on the the small yield response difference between seeding rates and question the optimal farmer return above seed cost. If you were to look only at that factor the optimal seeding rate would be ~100,000 seeds per acre even at a late May planting (Table 2). Though those numbers are very appealing I would caution growers to not go this low if they have uneven or rocky fields as harvestabilty will be a challenge with a lower soybean pod set. I would also not go this low in fields that are prone to drought as the rows will be slower to canopy and lead to greater soil water evaporation and subsequent weed competition. This leads us to waterhemp and its wonderful biology of delayed germination and prolific seed set. The point I am trying to make is this is a system and as Paul Harvey so eloquently stated……”now for the rest of the story”!
  4. Figure 1. Soybean seed yield response to seeding rate for soybean planted in Late May and June in IA, WI, and SD.

Table 1. Mean soybean seed yield response to seeding rate for soybean planted in Late May and June in IA, WI, and SD.

Soybean seeding rate

(1000 seeds per acre)

Soybean Seed Yield

(bu per acre)

160 67.3 A
140 66.6 AB
120 66.0 B
100 65.8 B
80 63.8 C
60 61.6 D
Tukey-Kramer Least Squares Means (Alpha=0.05); LS-means with the same letter are not significantly different.

Table 2. Return above seed cost at various market prices for seeding rates over 60000 seeds/acre.

Seeding rate


Yield difference compared to 60000 seeds/a

Soybean market price ($/bu)









——– ——– $/acre —————












































Based on $65.00/140000 seeds

Soybean Replant Decisions: Just the Facts Jack!

The Twittersphere is erupting with pictures of soybean beginning to crack and emerge. As we finalize #plant18 and start to assess our soybean stands here are a few items to contemplate.

  1. Get an accurate stand assessment. We are often drawn to the worst areas of fields and over-blow how bad the overall stand really is. You can go old school and use the tape or hula-hoop method or try a digital approach such as Bean Cam the WSMB funded soybean replant app!
    1. Link to the app store for iPhone and iPad
    2. Link to the app store for Android

      Bean Cam app calculations/results.

  2. An effective stand is obviously important to maximize soybean seed yield. However the downside yield risk for a sub-par stand is minimal until stands fall below 50,000 plants per acre. The synergy of early planting coupled with breeders adding 3x yield to soybean branches at low populations have effectively reduced the yield penalty for thins stands by 1/2 (Suhre et al. 2014) . Therefore we recommend the following.
    • Early planted soybean yield is maximized with stands that range from 100,000 (high yield environment) to 135,000+ (low yield environment) plants per acre.
    • When soybean stands are less than 50,000k plants per acre, inter-plant new seed with a similar maturity into the existing stand. DO NOT TEAR UP THE STAND AND START OVER.
    • When stands fall between optimal and 50,000k plants per acre Think Twice Before Replanting Soybeans! Our data shows a nominal ~2 bu yield increase in this situation. Even if you have a “free replant” guarantee the numbers don’t make economic sense. As a grower you are better off investing $$$ in an effective in-season residual herbicide to control weeds such as Palmer and waterhemp.


Gaspar, A. and S.P. Conley. 2015. Responses of canopy reflectance, light interception and soybean seed yield to replanting sub-optimum stands. Crop Sci.55: 377-385. doi: 10.2135/cropsci2014.03.0200

Suhre, J.J., Weidenbenner, N., ‡Rowntree, S., Wilson, E., S., Naeve, S. Casteel, S.P. Conley, Diers, B., Esker, P., Specht, J., and Davis, V. 2014. Soybean Yield Partitioning Changes Revealed by Genetic Gain and Seeding Rate Interactions. Agron. J. 106:1631–1642.