Summer is a season of fun; but for soybean plants, summer can be anything but pleasant. July and August often bring a variety of serious stresses, including water challenges (too much or, more often, too little), excessive heat, and disease and insect pressure. Though these stresses can and do lead to yield loss, there are things you can do in-season to help mitigate the situation. Here are a few ideas to help minimize in-season yield loss.

4 steps to minimizing in-season yield loss

1. Use in-season imagery to identify stressed areas.
2. Dig up some roots; take soil samples.
3. Look at leaves.
4. Increase your management; take tissue samples.

Use in-season imagery to identify stressed areas.
Whether the stresses in your soybean fields result from lack of fertility, drainage problems, compaction or something else, satellite imagery enables you to see crop development variability in each field. This lets you determine what is causing problems so that you and your local agronomist can address them promptly.

In-season imagery is also an excellent tool for determining where to take tissue and soil samples to identify nutrient deficiencies, and to calculate variable-rate prescriptions to fertilize undernourished parts of the field. It can also help you decide where to place crop protection products.

Dig up some roots.
As a complement to in-season imagery, get out into your fields with a shovel, dig up some roots and inspect nodules to make sure they are developing well and are insect- and disease-free. If you do spot problems, address them with the appropriate crop protection product. If a root dig or soil sample shows a problem with soybean cyst nematodes or fungal diseases, for example, you can get on it right away.

Look at leaves.
Keeping the trifoliate and petiole healthy is critical, because this leads to healthy flowers and pods. If you can keep one additional pod per plant, you can garner between 2 and 2.5 bushels of yield. If you can keep that leaf healthy, there’s a chance you can keep that pod healthy and prevent abortion. Keep fungus and rust away from that leaf, and keep insects from chewing holes in it, because a leaf with holes in it doesn’t capture sunlight effectively. This is where you can get aphids. R1 (first flowering) is an excellent time to fertilize. Check in at R3 to ensure pods are healthy.

Increase your management.
Soybeans respond to management. A common practice here in Illinois and throughout the Midwest is putting two years’ worth of fertilizer down just ahead of corn and letting it slide over into soybeans. What happens is, the corn uses pretty much all of that fertilizer, especially with the tremendous corn yields the past couple of years. Be sure you fertilize in the year you’re planting soybeans. Soybean plants like fertilizer, and they’re likely to perform better when it is adequate. Taking a tissue sample using a program such as NutriSolutions 360™ from WinField can determine what nutrients your soybean plants may be lacking.

Next year, plant treated seed.
At our WinField Answer Plot® in Springfield this past May, untreated soybeans showed tremendous flea beetle feeding, while the treated beans planted right next to them had no flea beetles. So the effectiveness of applying not only a fungicide, but also an insecticide, on soybean seed (for example, Warden® CX seed treatment) can be a huge advantage at the start of the season. And, new this season, ILeVO® seed treatment offers protection against a major soilborne soybean disease, sudden death syndrome (SDS).

So, enjoy the summer! And do all you can to make your soybeans thrive!

Share This Story

About the Author: Bob Beck

Dr. Bob Beck is a WinField agronomist out of central Illinois. Feel free to contact him with any questions at