Tag Archives: yield

Estimating Soybean Yields

Although it’s hard to accurately estimate soybean yields until maturity, doing so can give you an idea of your crops potential this year or differences between fields or soil  types.  Maybe you’re considering entering the soybean yield contest or maybe you just want some peace of mind.

Here are some general guidelines for estimating soybean yield.  Again, estimating soybean yield is inaccurate unless detailed sampling is done late in the growing season.  Estimates are usually not very good until the soybean approaches physiological maturity (R7).  Only about 50% of the total seed dry matter has accumulated by the R6 development stage.  Stresses during the R6 to R6.5 stages can result in large yield losses mostly by reduced seed size, but also by reduced pods or beans per pod.  After R6.5, stresses will cause a much smaller loss. 

To estimate yields, follow the steps below.  Be sure to sample in 5 to 7 different areas of the field.

1. Determine the number of row feet needed to make 1/1000th of an acre from the table below.  In narrow rows, one may use 3 or 4 side-by-side rows instead of one long row

2. Determine the plant population per acre.  Count the number of plants for the row feet determined above in 5 to 10 randomly chosen area of the field.  Multiply this number by 1000.  Average the number of sampling areas.  Note that the more areas of the field that you sample, the more accurate are your estimates.

3. Determine the number of pods per plant.  As you are making your stand counts, pull up 5 consecutive plants in the row you counting.  These 5 plants should be growing next to each other.  This will insure that you don’t just pull the best looking plants in the row.  Also, try to avoid gaps in the row as the plant next to the gap will have more pods than the average plant. Count the number of pods on these plants within the sample area and average.

4. Determine the pods per acre.  Multiply the plant population (step 2) by the pod average (step 3).

5. Determine the number of seeds per acre.  Multiply the number of pods (step 4) by 2.5 seed per pod.  This is an average number of seed per pod for most varieties.  Some varieties may have more, some less.

6. Determine pounds of seed per acre.  Divide the seeds per acre (step 5) by 3000 seeds per pound.  This number can vary from 2500 to 3500.  Higher numbers represent smaller seed that are more likely during late-season drought.  Smaller numbers represent seed that form with abundant August/September rainfall.  You may want to obtain a low, medium, and high estimate.

7. Determine the yield estimate.  Divide the pounds per acre (step 6) by 60 pounds per bushel.

As an alternative to calculating your numbers, you can use the chart below to determine how many pods or seed per pod you would need at three different plant populations to obtain a certain yield.

Virginia Wheat & Barley Yield Contest

The Virginia Grain Producers Association has announced the rules and entry forms for the small grains yield contests.  This is a great way to promote good small grain management and for top producers to be recognized. 

Click Here for Virginia Barley Yield Contest Rules

Click Here for Virginia Hard Wheat Yield Contest Rules 

Click Here for Virginia Wheat Yield Contest Rules

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.

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.

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

 

Virginia 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.
There are four Soybean Yield Contest categories: 1) Full-Season, Non- irrigated; 2) Double-Crop, Non-irrigated; and 3) Irrigated (Full-Season or Double-Crop; and 4) Most Efficient. 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 harvest of barley or wheat; thus harvesting two crops from the same field in the same year. If soybeans are planted after a cover, silage, or hay crop of small grain, then the entry will be considered full- season. 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. Yield alone (bushels/acre) determines the winners in the first three categories.
Notice of intent to participate must be submitted to your county/city Extension Agent’s office 5 days before harvest or in an acceptable time frame for your Extension Agent. Extension Agents shall maintain the original set of record sheets and applications of all participants and send a copy to Dr. David L. Holshouser, Extension Agronomist, Tidewater Agricultural Research and Extension Center, 6321 Holland Rd, Suffolk, VA 23437 by Dec. 31.
Application forms and a complete set of rules and regulations can be found on the Soybean Yield Contest website.

Finishing Out the Soybean Crop – What do we need for Good Yields?

In general, we’ve had a good, but not great year for soybean in Virginia.  Although many areas were hit with a 3 to 4 week dry spell during July, August rains kept us in the game.  However, we did not see the ample  rains or cool temperatures that we experienced in August of 2017, which resulting in record yields.  Below is a summary of August rainfall and temperature anomalies for the U.S.

 

 

 

 

 

 

 

 

As you’ll notice,  we had about average or slightly below average precipitation and average to slightly above average temperatures for most of Virginia’s soybean growing areas.

So, I do not suspect that our yields will be as good as last year.  Still, our earlier-maturing varieties planted in April or May should yield quite respectably considering that most have made over 50% of their yield – they have reached the R6 stage (see photo below).  Yield of our later-maturing varieties, planted in May and early June, and our double-crop plantings are not quite there yet – much of our yield is yet to be determined – R5 soybean have only made roughly 25% of their yield at that time.

So, what do we need for good yields?  Rain is obvious.  Full-canopied plants with adequate soil moisture will draw about 0.25 inches of water/day from the soil.  But, we also need cool temperatures – soybean do not generally like 90+ degree days, especially when forming seed.

Below is the 10 day rainfall and temperature forecast for the U.S., and it does not necessarily look good for us.  Note that the rainfall is predicted accumulation and the temperature map shows anomaly.  Although we should get some rain this weekend only (more in northern parts), temperatures are supposed to be above average.  But, forecasts are only forecasts.  The weather does change.  I hope we will get the needed rainfall that they are predicting this weekend.  But a big ridge appears to be setting up over the Mid-Atlantic states for next week.  This usually means warm weather and only at the edges of ridges do we normally see rainfall – note the heavy rainfall predicted from Nebraska through Michigan.

 

 

 

 

 

 

I don’t mean to discourage, just to inform.  We still have decent soil moisture, at least in the subsoil.  With rain this weekend, we should get through next week without too much harm to the crop.

Our double-crop soybean (assuming late maturity group 4’s and group 5’s planted in late June to July) are just now in the R5 stage – it usually takes 80 to 100 days from planting to reach R6, depending on maturity and planting date.  So some timely September rains will usually result in good double-crop soybean.

When will our yield be “made”?  Below is table showing the number of days to soybean physiological maturity (R7; 95% of yield has made).  When can we expect to be harvesting our soybean?  Full maturity is reached about 2 weeks after R7 and harvest can proceed after the soybean have dried down to a harvestable moisture, usually within a week after R8.

Small Grain Yield Contests Show High Yields Across the Commonwealth

The Virginia Grain Producers Association is proud to announce the 2018 Virginia Wheat and Hard Wheat Yield Contest Winners.

This year’s winners come from counties across the Commonwealth and have once again proven that Virginia producers are capable of achieving exceptional yields. Yield contests, such as this, are an important element in our mission to highlight and communicate the accomplishments of Virginia agriculture to our industry partners and the general public. The top-ranked growers will be given cash prizes donated by the providers of their winning seed, and will be fully recognized with a plaque presented by one of our industry leaders at the Virginia Grains and Soybean Annual Conference next February.

At 108.6 bushels per acre, Alan Welch’s wheat took first place. Katie Myer’s hard wheat yield of 85.7 bushels per acre claimed first prize.

The hard wheat portion of the contest is sponsored by Mennel Milling to highlight the planting of hard wheat in the Commonwealth. Hard wheat is primarily used as a bread wheat. The majority of the wheat grown in Virginia is soft red winter wheat, which is used in bakery products such as flat breads, cakes, pastries and crackers.

 2018 Virginia Wheat Yield Contest Winners

 1st Place $700: Alan Welch, Welch Farms, Inc., Northumberland County

108.6 Bu/Acre, Pioneer 26R59

2nd Place $500: Justin Welch, Welch Farms, Inc., Northumberland County

105.5 Bu/Acre, Pioneer 26R59

3rd Place $300: Paul Davis, Davis Produce, New Kent County

89.6 Bu/Acre, AgriMaxx 463

 2018 Virginia Hard Wheat Yield Contest Winners

 1st Place $700: Katie Myer, Richmond County

85.7 Bu/Acre, Vision 45

2nd Place $500: Paul Davis, Davis Produce, New Kent County

78.5 Bu/Acre, Vision 45

Many thanks go out to The Mennel Milling Company of Virginia, Pioneer, AgriMaxx, and UniSouth Genetics (USG) for sponsoring the Small Grain Yield Contests.

Virginia Soybean Yield Contest Results Announced

2017 was a great year to grow soybean.  We set a new record for average soybean yields in Virginia and most were generally happy with their soybean crop.

Although we did not break Keith Brankley’s 2012 Virginia record of 109 bushels per acre (and this was not irrigated), we did induct 3 new members into the 100-bushel club with the help of irrigation.  We also inducted 3 new members into the 90-bushel club and 4 new members into the 80-bushel club without the aid of irrigation.

I invite you to the Virginia Grain and Soybean Conference to share in their success and maybe get a few pointers on how to be the first inductee into the 110-bushel (or greater) club in 2018.

Below are a list of winners:

Double-Crop Contest

3rd place – Patti Craun with 66.8 bu/A using Pioneer P46T30X

2nd place – Kevin Craun with 67.2 bu/A using Pioneer P46T30X

1st place – Steve Smith with 72.3 bu/A using Channel 4916RX/SR

Full-Season Contest

3rd place – Michael Downing with 92.6 bu/A using Asgrow AG45X6

2nd place – Stephen Ellis with 93.8 bu/A using Axis 3916NR

1st place – Curtis Packett with 96.2 bu/A using Asgrow AG4135

Irrigated Contest

3rd place – Steve Hudson with 100.8 bu/A using Channel 4916R2X/SR

2nd place – Jonathan Hudson with 101.5 bu/A using Channel 4916R2X/SR

1st place – Frank Hula with 104.2 bu/A using Local Seed Co. TS3959R2S

2016 Soybean Yield Contest

The Virginia Soybean Association in cooperation with Virginia Cooperative Extension would like to announce the 2016 Virginia 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. With the help of various seed companies, we reward and promote the achievements of Virginia’s most productive soybean farmers.

There are four Soybean Yield Contest categories: 1) Full-Season, Non-irrigated; 2) Double-Crop, Non-irrigated; and 3) Irrigated (Full-Season or Double-Crop; and 4) Most Efficient Yield (MEY). First, second, and third place winners of the full-season, double-crop, and irrigated contest will be recognized with appropriate trophies or plaques. In addition, cash awards of $200, $100, and $50 will be presented to the first, second, and third place winners in each of these categories. The winner of the MEY contest will receive a plaque declaring him or her the most efficient soybean producer in Virginia for that year.

Printable entry forms and contest details can be obtained from your County Agent or on the Soybean Extension and Research website.