By Dusty Sonnenberg, CCA, Ohio Field Leader: a project of the Ohio Soybean Council and soybean checkoff
Amber waves of grain (often pictured as fields of wheat, swaying in the summer breeze) are as much of Americana as baseball, hotdogs, and apple pie. Incorporating wheat in a cropping rotation, however, has more benefits than just a pretty summer picture.
“The farms we regularly raise wheat on have had slightly better yields in the
other crops,” said Brad Haas, Wood county farmer, and past president of the Ohio Wheat Growers Association. “Those farms have had a slightly better yield and also lower diseases levels.”
While Haas likes raising quality wheat, and has done so for the past several decades, the biggest challenge he has faced the last two years has been finding fields available to plant in the right window after the fly free date that were fit, and did not have late soybeans in them.
“I like to plant wheat as close to the fly free date as possible,” Haas said. “I have found that having fields available to plant within about a week to 10 days of the fly free date consistently yield noticeably better than those planted a few weeks after fly free that had later beans and were not available early.”
Haas says if a farmer wants to raise quality wheat, they need to take it seriously.
“Raising quality wheat takes planning,” Haas said. “You need to raise it on your better ground, which in our case is well-drained Hoytville clay. Then you need to treat it as serious as you would if it were a 200+-bushel corn crop.”
Incorporating wheat in a three-crop rotation begins with variety selection.
“Just like corn and soybeans, selecting the best variety with the right disease resistance for the specific field is the first step,” Haas said. “Having good drainage is the next step. Like the other crops, wheat does better on well-drained soils. Some guys plant wheat in those wet fields so they can get in earlier in the summer to install drainage tile, but to get the quality and good yields, you need to have well-drained soils to begin with.”
Wheat is not just a crop to plant and walk away from.
“Spring management is also very important,” Haas said. “A farmer needs to pay attention to the timing of topdressing and the uniformity of application. Weed control is also important in the spring to be able to have a clean harvest and quality weed free crop in the summer.”
Raising quality wheat also includes the use of fungicides in some years.
“We typically will make a fungicide application for disease management,” Haas said. “Back in 2017 we had a dry year, and several of the varieties we raised had good resistance, so that year we did not apply any and still had good success, but with this year’s weather conditions, we decided to apply a fungicide. We attended a workshop put on at the OARDC Northwest research station by Dr. Pierce Paul about 10 years ago. Pierce talked about understanding the wheat growth stages and his data showed we have a little longer window than I originally thought to make our application.”
Haas has found that wheat fits well in his crop rotation in a variety of situations.
“I like no-tilling soybeans into wheat stubble in the spring,” Haas said. “Sometimes the volunteer wheat that comes up helps like a cover crop to get the soil fit and we no-till into it. We also have followed wheat with a corn crop because the wheat lets us get some late summer ground work done to get the fields ready for corn in the spring.”
According to the Ohio Agronomy Guide, a three-year rotation of corn-soybean-wheat appears to be optimum for sustained yield of all three crops. Crop rotation is the most effective method to reduce pathogen populations that affect the three crops in the sequence. The purpose is to provide enough time away from the host plant for pathogens to die out before that crop is planted again. Wheat should never follow wheat in a rotation.
Research was conducted by Laura Lindsey, Ohio State University Extension soybean and small grains specialist, and Soledad Benitez Ponce, OSU Extension plant pathologist, incorporating wheat into a traditional corn-soybean crop rotation. The project was facilitated at the OARDC Northwest and Western Research Stations in Wood and Clark counties, respectively.
In a two-year study conducted in 2018 and 2019 comparing plots having a corn-soybean rotation to plots with a corn-soybean-wheat rotation, the soybean yields usually increased when wheat was included in the rotation. The yields were variable, but the average soybean yield increase was 3 bushels per acre.
Along with the subsequent soybean yield, other factors were evaluated. At the Western Research Station, the soybean stand was significantly improved when wheat was included in the rotation. “We had a stand of 109,000 plants per acres in the plot that included wheat in the rotation, compared to a stand of 89,000 plants per acre where wheat was not in the rotation,” Lindsey said. “The weather conditions in 2018 had heavy rains after planting. We observed a similar trend in one of the cover crop studies the same year. When we had a cover crop included in the rotation, the soybean stand was improved.”
The thought is that the improvement may have been a result of better water infiltration, although it was not specifically measured. Lindsey hopes to continue the study of this factor in coming years.
Another finding from the research was an increase in the level of soil organic matter.
“In three out of four environments (site-years), the soil organic matter increased when wheat was included in the rotation,” Lindsey said. “The increase in the soil organic matter ranged from an increase of .2% up to .68%.”
The study was maintained in a complete no-till environment. There were other noticeable benefits the researchers’ observed when wheat was included in the rotation, (although not specifically measured). Having a wheat crop in the rotation decreased soil erosion during the winter and early spring. The wheat also serves as a non-host crop to soybean cyst nematode (SCN), and as a result, SCN numbers should decline in those environments where wheat is included in the rotation.