Which soybean variety is best suited to my region? State variety testing programs provide critical research to help answer that question by evaluating hundreds of soybean varieties every year across multiple locations within a state. But what if we think beyond the bounds of our state borders when it comes to variety evaluation?
While a single state alone provides valuable data, our growing regions often cross state lines. A location in southeastern Virginia may share more similarities to sites in eastern North Carolina than it does to the Northern Piedmont of Virginia. Furthermore, by combining variety testing data across multiple states, we can create a more robust dataset that allows us to better predict which varieties are best suited to specific regions and growing conditions.
Pulling and combining data from select locations within multiple state variety testing programs can be a daunting task. Over the past year, a team of variety testing coordinators from Tennessee, Arkansas, Kentucky, North Carolina, and Virginia have been working to make that process a lot easier. Through funding from the United Soybean Board and in collaboration with Centrec Consulting Group, LLC, we created a tool that will allow users of variety test data to combine and visualize soybean variety testing data across multiple states in the Mid-South. This new tool is available at https://marketviewdb.centrec.com/?bi=MidSouthVarietyTrials.
In addition to choosing locations, another key component of this database is the ability to filter the results to include only the relative maturities, brands, and herbicide tolerances that you want. It can also let you chose whether to include irrigated and/or non-irrigated, or full-season and/or double-crop sites. You can also chose the soil textures that you are interested in.
I won’t go into the details of how to use the site in this blog. But, try it out. Contact me with questions or comments.
The database currently contains 2018 – 2020 data but will be updated as 2021 soybean variety trial data becomes available. We hope that you find this tool useful. We would value your feedback/suggestions as we continue to refine this product to better meet stakeholder needs. A brief survey can be found at https://utk.co1.qualtrics.com/jfe/form/SV_6u5lHEwEOXnXODA.
The database described in this article was developed with support from the United Soybean Board.
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.
It’s hard to believe, but June is here and we need to start thinking about increasing our soybean seeding rates. I’ve been recommending only 100 to 115 thousand seeds per acre for full-season production, enough to give you 70 to 80 thousand plants – yes, that’s all you need to maximize yield.
But as the season gets shorter, yields will start falling with delays in planting date. On average, we lose about 1/2 bushel/acre per every day we delay planting after the middle of June. The graph below shows the results of last year’s 4-state early wheat harvest/soybean planting double-crop study. Note that yield does not decline very much during the first week or two of June, but rapidly drops off afterwards.
The main reason for this yield decline is that the crop struggles to develop enough leaf area to capture 90-95% of the sunlight by early pod development, due to the shorter growing season. We can alleviate some of this by narrowing rows and increasing seeding rate.
I usually suggest that farmers plant enough seed to result in a final plant population of 180,000 plants/acre for double-crop soybean. That means planting 200,000 to 220,000 seed/acre. Yes that is a lot of seed, but my research shows that yields (and profit) continue to increase up to this seeding rate, especially when planting is delayed until late-June and early-July.
There are stipulations. More productive soils and irrigated soybean usually require less seed. Good years that allow lots of quick growth require less seed (but who can predict a good year?). Later maturity groups may require slightly less seed. Less seed are needed as you move south (growing season is longer and you can plant a later relative maturity). I think that a soil profile that is full of water at soybean planting (this year) might allow less seed to be planted – but I have not documented that – It just makes sense to me that plants will grow better when the small grain has not depleted most of the subsoil moisture.
What about now? How many seed/acre do we need to plant in the first week of June? Here are my suggestions. Keep in mind that these are general guidelines; you need a gradual increase in seed/acre. I’m assuming 80 to 85% emergence for June/July plantings. To easily determine how many seed you need per row foot, see VCE pub 3006-1447, Suggested Soybean Seeding Rates for Virginia
VIRGINIA SOYBEAN FIELD DAY Thursday August 20, 2015
Eastern Virginia Agricultural Research & Extension Center 2229 Menokin Road Warsaw, VA 22572 (804) 333-3485
Sponsored by Virginia Soybean Association Virginia Agricultural Experiment Station Virginia Cooperative Extension
Join us to see the latest research on soybean varieties, disease and weed management, IPM and sorghum varieties. Experts will also demonstrate no-till drill maintenance and update you on the mid-Atlantic double crop initiative. Registration begins at 8:00 am and field tours begin at 8:50 am. The program will end at noon with a delicious meal by Nixon Catering.
– Soybean Disease Management – Dr. Hillary Mehl
– Soybean Weed Management – Dr. Mike Flessner
– Soybean Insect IPM – Mr. Mike Parish and Drs. Sean Malone and Ames Herbert
– No-Till Drill Maintenance – Mr. Keith Burgess
– Grain Sorghum Management – Dr. Joseph Oakes
– Roundup-Ready Public Soybean Varieties – Dr. Bo Zhang
– Mid-Atlantic Double-Crop Soybean Initiative – Dr. David Holshouser