Author Archives: David Holshouser

About David Holshouser

David serves as Associate Professor & Extension Agronomist at Virginia Tech’s Tidewater Agricultural Research and Extension Center. He provides leadership for agronomic extension and research programs that lead to profitable and environmentally-responsible agriculture.

Soybean Yield & Quality – My Predictions, Cautions,

I’ve been very hesitant to write this article and I’ve held off for several weeks, hoping to have more yield results in before saying anything. But I’ve seen enough so far in my observations of our variety tests as well as other fields that I think what I’m about to write is fairly accurate. My main concern all along was how much the Aug and September drought hurt us. Below is the rainfall anomalies in the U.S. It’s easy to see that we were way below average with the exception of southeast Virginia and parts of the Eastern Shore.

First, the maturity group 3 and early-4 soybean should be the cream of the crop this year. The yields that we are seeing is impressive and I’m hearing the same from others. These maturities appeared to avoid the drought for the most part. Plus the seed quality is very good (somewhat unusual for early-maturing varieties) due to the lack of September rain although we experienced another warmer-than-average September. This is us harvesting in Orange County last week – yields were in the 60’s and 70’s.

What about the later-maturing varieties that we grow the most of? A casual look at the soybean remaining in the field seem to indicate that we have a pretty good pod load in most cases, with late-planted soybean being the exception. Although the drought did hurt us, it’s somewhat hard to see now. Again, that’s from a casual observation. A closer look at the late-4’s reveal that the yield potential is still pretty good (see photos below; we did not harvest these due to a few varieties not yet being fully mature). Although we had a few aborted and small seed, most were intact. Keep in mind that this is a very good soil (Davidson clay) and the area did pick up a few rains that other parts of Virginia did not.

But what about our group 5 soybean? They don’t look nearly as good. Although pod abortion was not too bad, we had a good deal of flat pods and seed abortion within pods that were not completely flat where all seed were aborted. Don’t confuse the flat seed remaining in the pod with stink bug damage. Sting bug damage will usually result in discolored seed (there is one seed below that shows this); the small/flat seed due to drought-stress are usually not discolored. There was a pretty striking difference between the late-4’s and mid- to late-5’s; in general, the later maturity the more seed abortion.

Although I’m not seeing another concern, I think that it’s worth mentioning. A few years ago we observed drought-related green seed. These were not from late-maturing green stems or scattered plants. They were from the plant dying before the crop matured. This is only the case where we have extreme drought conditions and usually on a very low water-holding-capacity soil. But, I am seeing some dead leaves sticking to the stem, an indication of early plant death (see photo below) on some of our later-maturing varieties. While I hope this is not and issue this year, I did want to bring it to your attention. Too much green seed in a load will result in a reduced price for the crop.

Finally a note about green stems and branches. Anytime that we have a high amount of pod and/or seed abortion we can end up with some green stems. In some cases, we’ll even have green leaves on the plant although the seed are dry. This sometimes occur with high infestations of brown marmorated stink bug along the edge of a field or with certain viruses. But, drought can also cause this.

In addition to green stems, I’m getting reports of dry seed on the main stem (basically a mature plant), but the plant contains many green stems with immature seed. We have seen this in past years in low areas of the field where an overabundance of rainfall occurred early in the vegetative stages followed by a short intense drought (which I think stopped main stem growth) and by low light conditions. Once the drought was over, branch growth then took over. Branches are always behind the rest of the crop in maturity and the branches basically behave indeterminately (lower pods are more mature than upper pods), resulting in many immature seed at harvest. the last two pictures below are from late-May planted soybean in Mecklenburg County this year. At that location, about 10-12 inches of rain fell in the early vegetative stages and the soybean did not grow for the next 3-4 weeks, even with all this moisture. There was also lots of deer feeding. This was of course followed with the drought in Aug and September. While that situation was not exactly the same as the one I described previously, the problem is similar.

Regardless, one has to decide whether to harvest now and get the bulk of the crop before it shatters or wait until the rest of the seed to dry down. You definitely don’t want a lot of “butterbeans” in the load, but neither do you want lots of high-moisture seed that will affect overall moisture and storability. Shattering in today’s varieties are not as bad as in the past, so I’d wait a few days.

EVAREC Soybean Field Day is This Tuesday

The Eastern Virginia Agricultural Research and Extension Center (EVAREC) Soybean Field Day is this Tuesday, Sept. 24. The field day begins at 8:45 am and tours will begin promptly at 9:00 am. There are a number of different topics to be discussed, all supported by the Virginia Soybean Checkoff. The 2019 full-season soybean variety test will also be available for viewing. Lunch will be served by Nixon’s Catering. We look forward to seeing you there.

The EVARE is located at 2229 Menokin Road, Warsaw, VA 22572. For more information, contact Dr. Joseph Oakes, EVAREC Superintendent at 804-333-3485.

Group 1 Field Tour Schedule

  • 8:45 – Welcome & Introductions; Load Trailers to ACR 2
  • 9:00-9:20 – Integrated Pest Management Approach for Soybean
  • Dr. Sally Taylor
  • 9:25-9:45 – Food Grade Soybean Breeding
    • Mr. Nick Lord
  • 9:45 – Load Trailers to Y1
  • 9:55-10:15 – The Best Maturity Group for Your Farm
    • Dr. David Holshouser
  • 10:15-10:30 – The Use of UAV in Crop Research and Production
    • Dr. Joseph Oakes
  • 10:35-10:55 – Roundup-Ready and Conventional Soybean Breeding
    • Dr. Bo Zhang
  • 11:00-11:20 – Weed Management in Soybean
    • Dr. Michael Flessner
  • 11:20 – Walk to Seed Lab

Program & Speakers in the Seed Lab

  • 11:40 – Begin Indoor Program
    • Dr. John Fike: VT Forage Extension Specialist – Hemp Production
    • Dr. Mike Evans: VT School of Plant and Environmental Sciences
  • 12:00 – Lunch is Served: Nixon’s Catering

Thank You to Our Field Day Sponsors!

Crabbe Aviation                       Ryan Ellis

Frazier Quarries                      UniSouth Genetics

James River Equipment            Virginia Crop Improv. Assoc.

Montague Farms

Virginia Soybean Yield Contest

Any grower (owner-operator, tenant, or tenant-landlord team) who is a member of the Virginia Soybean Association and produces 10 acres or more of soybeans within Virginia’s boundaries is eligible to enter this year’s soybean yield contest.

The purpose of the Virginia Soybean Yield Contest is to emphasize and demonstrate the practices necessary to produce maximum economic yields, to recognize those producers who grow high-yielding soybeans, and to gather data on the practices utilized by these outstanding producers.  The Virginia Soybean Association in cooperation with Virginia Cooperative Extension sponsors this program. The Virginia Soybean Association in cooperation with Virginia Cooperative Extension sponsors this program.

There are three Soybean Yield Contest categories: 1) Full-Season, Non-irrigated; 2) Double-Crop, Non-irrigated; and 3) Irrigated (Full-Season or Double-Crop).  A full-season system is defined as the grain or seed harvest of one summer crop (soybean in this case) from the same field in one year. Double-crop is defined as planting soybean immediately following grain or seed harvest of barley, wheat, or rapeseed; thus harvesting two crops from the same field in the same year.  If field has been irrigated one or more times, the entry will be considered an irrigated field and the will be placed into the irrigated contest.

Details can be found in the attached document below. Please consider entering the contest.

Eastern Virginia AREC Soybean Field Day – Sept 24, 2019

Join us for the 2019 Eastern Virginia AREC Soybean Field Day in Warsaw on Sept. 24.

Field Tour Topics
• Roundup-Ready and conventional soybean breeding: Dr. Bo Zhang
• Food-grade soybean breeding: Dr. Bo Zhang
• The best maturity group for your farm: Dr. David Holshouser
• Weed management in soybean: Dr. Michael Flessner
• Integrated pest management approach for soybean: Dr. Sally Taylor
• Use of UAV in crop research and production: Dr. Joseph Oakes
• Industrial hemp production: Dr. John Fike

Registration begins at 8:00 a.m.
➢ Field research tours begin at 8:30 a.m.
➢ Lunch: 12:00 p.m.

Please register by emailing Joseph Oakes at jcoakes@vt.edu

2019 Virginia Ag Expo Comes to Charity Hill Farms in Caroline County

The Virginia Ag Expo is the largest agricultural field day held in the Commonwealth of Virginia. As an educational, marketing and social event, farmers and agribusiness look forward to the Virginia Ag Expo each year. This year’s event will be held at Charity Hill Farm in Ruther Glen, VA on August 1st.

Charity Hill Farm is an 800-acre farm owned and operated by The Smith Family in Caroline County.  Its active members are Steve and Cindy Smith and their son Chris. The farm has been in the Smith family for six generations and is a certified Virginia Century Farm.  Originally known as Smith Dairy Farm, the dairy cows were sold in 2006, and the operation began its transition to beef cattle with the help of the Smith’s daughter, Kendal, who is now a large animal veterinarian in Nebraska.  Over the last 8 years, the Smiths have focused on growing and perfecting their 200 head beef herd, and Chris began retailing their BQA Certified, USDA inspected beef directly to the consumer in 2017.  The Smiths additionally farm 1,200 acres of grain crops in Caroline and Spotsylvania counties, 150 acres of hay and 55 acres of managed timber. Agritourism events are also hosted at Charity Hill, and they work to promote conservation initiatives. The Smiths are proud to have won the 2010 Hanover/Caroline Soil and Water Conservation District and York River Basin Clean Water Farm Awards.

Breakfast and lunch will be provided at the Ag Expo by Virginia food vendors.  Attendees will be able to eat any time from 7:30 AM to 2:00 PM.

Over 150 exhibitors and sponsors will have on display all of the most up to date equipment, goods and services for agricultural producers and property owners no matter how large or small.  Field tours will also be presented by many of Virginia’s top agricultural researchers, Extension Agents, and NRCS personnel.

The Virginia Ag Expo is sponsored by the Virginia Grains Producers Association and the Virginia Soybean Association, in cooperation with the Virginia Cooperative Extension Service.

Location: Charity Hill Farm, 9482 Golansville Rd, Ruther Glen, VA 22546

 

Harvest Wheat, Plant Double-Crop Soybean As Soon As Possible

The recent hot and dry weather is really drying the wheat down quickly.  We harvested our first wheat today (the moisture was ranging from 16 to 20%) and planted soybean immediately afterwards.  Just 2 days ago, the wheat grain moisture was in the mid-20’s!

That experiment is part of our ongoing efforts to harvest higher quality wheat and increase our double-crop soybean yields.  Now, I’m not advising you to harvest your wheat at 20% unless you have a buyer that will take it, preferably without a discount, or you have a way to dry down quickly.  High moisture wheat will heat up quickly and you will need to do something with it right away.

With that said, we have seen great benefits from harvesting higher moisture wheat and getting the soybean planted immediately.  Our Mid-Atlantic regional project conducted from 2015 thru 2017 found greater wheat yields and test weight, and greater soybean yields.  Our data is shown below.  Note that I’m only showing Virginia wheat data as the date where yield began declining differed among the states (this data was earlier as we moved south), but the general shape of the graph was similar.  Different colored symbols represent different years.

 

 

 

 

Note that our soybean yield usually start declining rapidly in mid-June.

In summary, there is benefit from harvesting wheat and planting soybean as soon as possible.  However, read the previous blog, To Plant or Not to Plant into Dry Soil, before making too many decisions.  Not only is our topsoil dry, but the wheat may have removed moisture much deeper – giving us little total soil moisture.

To Plant or Not To Plant Into Dry Soils

Rachel Vann, Extension Soybean Specialist – N.C. State University & David Holshouser, Extension Agronomist, Virginia Tech

Now that the weather has turned hot and dry, and with limited rainfall in the forecast over the next ten days, we are starting to get questions about continuing to plant soybeans or halting planting until we catch a rain. There is no consensus on what to do in this situation, but we aim to discuss the pros and cons of the different approaches in this blog post.

Soybean seed must take in 50% of its weight in water to initiate the germination process. Germination is not affected if the seed has imbibed water for 6 hours (seed is swollen, but seed coat in not broken), then it dehydrates to 10% moisture. If the seed has imbibed water for 12-24 hours (seed coat is broken but no radical has emerged) then dehydrates to 10%, germination may be reduced 35-40%. If the radical has emerged and the seed dehydrates to 10% moisture, few if any seedlings will survive (Holshouser, 2012). What we want to avoid with any approach discussed below is exposing the seed to enough moisture to start germination but not enough for the seed to get out of the ground.

The general optimum planting date range for planting soybeans across North Carolina was identified by Dr. Dunphy as May 1 to June 10. This optimum planting range varies from year-to-year based on rainfall, soil water holding capacity and soybean maturity, but the goal is to get the soybean plants to lap the middles before reproductive growth begins. We still have 10 more days before we get to the end of that optimum range this year and parts of the state have a chance for rain before June 10. Continuing to wait to plant is more of a concern for our growers who still have seed from early maturing varieties to plant (<MG5), as these varieties will have less time for vegetative growth prior to the beginning of reproductive development. The three major options growers in the region are facing are discussed below.

  1. Plant shallowly in the dry and hope for enough rain to get the seed out of the ground. If you decide to take this approach, you want to ensure you achieve uniform seed depth and that you are not allowing the seed access to moisture below the seed that could lead to variable emergence. This approach would be less risky in clean-tilled situation where you are more confident that you have dried the soil out at shallow depths. Dr. Dunphy said he has seen soybeans planted shallowly into dry conditions before that have sat in the ground >5 weeks and still had excellent emergence when rainfall occurred. The biggest risk with this approach is that you catch a small rain that allows the soybean seed to imbibe water but does not provide enough moisture to get the soybeans out of the ground. We would also suggest you exercise caution using this approach in a no-till situation where you would be more likely to see problems with lacking uniformity of moisture across the field leading to variable seed access to moisture and ultimately emergence variability. In many cases, part of the field will have adequate moisture to get the soybeans out of the ground, other parts will be completely dry as in tilled conditions, and much of the field will be in between. Those in-between areas are likely to have enough moisture to swell the seed and/or initiate germination but not have enough moisture to allow the seedling to emerge.    We have had several inquires on the impact of planting into dry conditions on soybean seed treatments. What we can say is that fungicidal seed treatments are less likely needed in this situation where we already have high soil temperatures and lacking soil moisture than they are in earlier planting situations where the soils are cool and wet.
  2. Plant deep to the moisture. Under most conditions, soybeans should be planted 0.75 to 1.5 inches deep. Soil temperatures are high enough right now to germinate and emerge quickly, even at deeper depths than recommended. But soybeans should not be planted deeper than 2 inches. We’ve talked to several growers and County Agents across the region who are not finding soil moisture until 3 to 4 inches deep; we definitely do not recommend planting this deep.  Growers should exercise caution using this approach if your soils are prone to crusting, because a heavy rainfall could seal the soil before the soybeans emerge. In addition, if the planter pushes the soil down a little in tilled conditions, creating a ridge of fluffy soil on each side, a heavy rain will cause this fluffy soil to move into that furrow and possibly add another ½ to 1 inches of soil to your depth.  If you are going to go this route, check the emergence score on the variety.
  3. Keep the seed in the bag until the next time we catch rain. This is the safest approach at this point. Based on historical data, we have another 10 days or so before we start seeing yield declines from delayed planting. Parts of the state have a chance of rain in the next 10 days. Data from recent research throughout the Mid-Atlantic shows that each day delay in planting past mid-June can result in a ½ bu/A or more yield loss and in general these yield declines begin in the second or third week of June; we still have some time before we get to that point.

Whatever decision a grower makes, uniform seed placement in critical to achieve uniform emergence and ensure each seed has as equal of access to water as possible. We have discussed the importance of uniform emergence in soybeans here: https://soybeans.ces.ncsu.edu/2019/04/how-important-is-uniform-emergence-in-soybeans/

In conclusion, there are advantages and disadvantages to each planting option discussed, but we still have time to plant soybeans in our region before we see drastic yield declines. All options discussed will likely result in delayed emergence due to environmental conditions.

Would Soybean Yields Rise If We Started Planting in April?

April planting is thought to have an advantage over May planting because we can shift the development of soybean to an earlier time of the year  where there is more sunlight.   More total sunlight per day should result in greater yields.  But, does this hold up in Virginia?  Likewise, an earlier variety will also shift maturity, and the critical stages of development, to a time of the year when the days are longer.  So in theory, planting early-maturing varieties early should result in the greatest yields.

My concern is that when you shift your development to earlier times of the year, you are also placing the most critical pod and seed development stages in a hotter and drier time of the year.  While you could possibly alleviate the dry part with irrigation, I know of no way to keep the temperature from rising.

To test these hypotheses, we planted 10 to 12 varieties ranging in maturity from late-3’s to early-6’s in April, May, and June at three Virginia locations in 2017 and 2018.  I’m not going to show the data because we found relative maturity responded differently depending on location, and it would just take up too much room to show all the graphs.  However, we have seen no benefit to planting soybean in April versus May, although April plantings did not usually yield less than May plantings.  Maturity group response depended more on location and when the rain fell.

So, I suggest that you base your planting date and or relative maturity decisions on your need to spread out planting or harvesting.  April planting date is OK, but not necessary for greater yields.  Keep in mind that soils are usually cooler in April, so it will normally take soybean longer to emerge than when planted in May.  Fungicides will be needed for April and early-May plantings.

Planting a slightly earlier maturing soybean is usually OK also.  For more information on maturity selection, see my previous blog, “Improving Your Soybean Variety Selection Decisions – What maturity is best?

If you do plant in April and/or want to use early-maturing varieties, then do this on your best soils.  If you move the critical stages of development to a hotter and drier time of the year, you’ll need the greater water-holding capacity of those soils.

Full-Season Soybean Seeding Rates: Maximize Your Yield and Reduce Your Risks

In general, high seed costs have resulted in a reduction in the number of soybean seed planted per acre.  For our full-season production system, most have reduced their seeding rate to 140,000 or less.  Some have even had success with rates as low as 80 to 100 thousand seed/acre.  My research over the years has shown that we only need, on average, about 70 to 80 thousand plants/acre to maximize our yield.  But is this too low? Yes, it could be – in some situations.

There is also interest in varying seeding rates.  I said many years ago that it appears that this is possible.  But our approach to variable-rate soybean seeding will be just the opposite of how we vary our rates with corn.  With corn, we increase seeding rate as our yield potential increases.  With soybean, we do just the opposite – we reduce our seeding rate as yield potential rises.  But, how much can we reduce seeding rate with rising yield potential?

To answer both questions – Is a final stand of 70 to 80 thousand plants too low? and How do I vary soybean seeding rates?, I analyzed over 10 years (over 25 experiments from 2003-2011) of on-farm and small-plot research to determine the optimal seeding rate for three different yield potentials.  The results along with my recommendations are shown below.

For low yields of 20-40 bushels/acre:

Plant 120 – 140 thousand seed /acre.

Why not less?  The data to the left indicates that the optimal seeding rate (area between the two vertical dotted lines) ranges between around 100 to 120 thousand seed/acre.  Why is this not my seeding rate.  There is too much variability in the data; therefore too much risk.  In some years, yields could have been reduced with this rate.  So, I’m hedging towards less risk at these yield potentials.

 

For medium yields of 40 to 55 bushels/acre:

Plant 100 – 120 thousand seed/acre.

You will notice that the optimal seeding rate has declined to around 90 to 110 thousand seed/acre.  Note that this is only about 10,000 seed less that the previous graph, but I lowered my recommendation by 20,000 seed.  Why?  There is little variability in these data; hence, I have more confidence.

 

 

For high yields of 55 to 70 bushels/acre:

Plant 90 to 110 thousand seed/acre.

Like low yield potentials, I’m starting to hedge a little here towards less risk although my data indicates that I can go lower.  There were cases where is took nearly 120,000 seed to get the maximum yields.

 

 

One comment that I get with these data is: “These data are old.  Does it still hold up with newer varieties?”  A good question!  So, I’ve conducted seeding rate experiments over the past 2 years and I’ll continue this coming year.  To summarize, the most recent data has not changed my recommendations – I think that these trends still hold true.  However, we did see some differences last year – a year of wet and cloudy conditions.  The data are below:

With our maturity group 4 trials, we saw yield continue to rise with seeding rate, and our yields were in the high range (about 50 to 60 bushels/acre).  But yields with the group 5 soybeans tended to level off at about 120 thousand seed/acre.   Why a different response and why did maturity group matter?

 

 

I think the answer is lack of sunlight.  Total photosynthetically-active radiation interception differences are one of the reasons that we get yield responses to seeding rate.  In most cases, this is a lack of leaf area; we are not intercepting all the light.  But, this was not the case in 2019.  We had what I normally consider enough leaf area, at least enough for a sunny year.  But we had less light in 2019.  The group 5 soybean did have more leaf area than the group 4 soybean; I’m assuming that these few extra leaves made up a little for the lack of light.  Cloudiness is one of the risks we take.  Still, I won’t change my recommendations based on last year since it was rather unusual.

In conclusion, if you want to chose the best full-season seeding rate in Virginia for your yield potential, my recommendations are:

Low yields: 120 to 140 thousand seed/acre

Medium yields: 100 to 120 thousand seed/acre

High yields: 90 to 110 thousand seed/acre