There is plenty of talk about going heavy on soybeans in 2017 due to economic considerations. At first glance, it seems reasonable. Some outlooks favor higher prices for soybeans right now vs. corn. And if you’re trying to trim costs, it’s generally thought to be cheaper to raise soybeans than corn.
We asked six agronomists to take a look at this issue. Are there downsides to planting soybeans after soybeans? Is it possible to manage around these issues? Are there situations where it would be better not to try to grow soybeans two years in a row?
You may have seen some of these articles on this website and in recent issues of Indiana Prairie Farmer. Thanks to Betsy Bower, Ceres Solutions, Terre Haute; Bryan Denning, Stewart Seeds, Greensburg; Danny Greene, Greene Crop Consulting LLC, Franklin; Steve Gauck, Beck’s, based in Decatur County; Greg Kneubuhler, G&K Concepts Inc., Harlan; and Bryan Overstreet, Jasper County Extension ag educator.
After editing their comments, some trends became clear. What was implied but not said openly was that because of lower yield potential and possibly higher input costs than for rotation soybeans, the economics of beans after beans may not turn out as favorable as you think.
Here are seven takeaway messages gleaned from these agronomists' comments.
1. Expect lower yields. Estimates vary from 5% to 20% lower. Actual results will also vary depending on the year, from no effect to a significant yield loss.
2. Reduce the crop budget yield for beans after beans. Based on lower yield potential due to loss of rotation effect, you should adjust the beans-after-beans budget when comparing to growing corn in that field. For example, if you usually pencil in 50 bushels per acre for yield, even at a minimal 5% yield loss, the new expected yield is 47.5 bushels per acre. If soybeans are $10 per bushel, that means you just lowered expected revenue $25 per acre.
3. Disease pressures will increase. Inoculum left from last year’s crop can infect this year’s crop. All that will be needed are the right weather conditions for infection.
4. Seed treatments will be more important than ever. If you thought this was the year you could cut out seed treatments and save money, you may want to rethink it. If you haven’t used seed treatments before, you may actually need to increase your budget up to $10 per acre, depending on your seed supplier.
5. Soybean cyst nematode pressure will increase. This means stepping up your management level and learning more about SCN resistance and races. You may need to rotate varieties and source of SCN resistance.
6. Expect weed issues to intensify. The need for residual herbicides and increased scouting was loud and clear. You may have to spend more on weed control than before.
7. Pay attention to soil fertility, especially potassium needs. If you thought you could skip fertilizer application and save money, you may need to rethink that decision too. You may need to apply fertilizer for soybeans, even if you normally don’t.
The bottom line is that revenue may go down and input costs may go up. Prepare a soybean budget for beans after beans, and compare it to your corn budget. That will provide a more accurate picture of whether it makes sense economically to shift some fields to soybeans after soybeans.