Soybeans University of Illinois test plots in August

University of Illinois test plots in August showed the makings of high yields. This year, 14 farmers in the state officially topped 100 bu./acre soybeans in the Illinois Soybean Association’s 100-bushel Challenge.

SPRINGFIELD, Ill. — Soybean yield challenge trials in Illinois this year showed steadily rising results, but there were a few exceptions to the expected.

Illinois soybean growers keep setting the bar higher with yield trends far surpassing national averages, said Dan Davidson, a consultant for Illinois Soybean Association.

For the last five years, Illinois farmers have averaged 6.5 bu./acre above the already rising national yield trend. Last year, Illinois was 10 bu./acre above the national trend, Davidson said at the ILSoyAdvisor Summit in Springfield Feb. 5.

It’s not all genetics, he said. The answer is in the management. Early planting has become one of the proven management practices to increase yields.

High yielders

The Illinois Soybean Association’s Yield Challenge, specifically the 100-bushel Challenge, has documented rising yield trends in the state. In 2014, Dan Arkels of Peru, Illinois, officially broke the contest’s 100-bushel barrier with 104 bu./acre beans. In the yield challenge that year, three other entrants topped 80 bu./acre, Davidson said.

The numbers kept growing. In 2018, 14 growers officially surpassed the 100 bu./acre goal; 30 topped 90 bu./acre; and 13 surpassed 80./bu. acre, he said.

In 2018, the 100-bushel Challenge winner was Paul Klein of Seymour, Illinois, with 110.94 bu./acre on his Champaign County field. In the irrigated category, Greg McClure broke the century mark with 110.19 bu./acre.

The 100-bushel bean achievers were concentrated in central Illinois, with Macoupin County having the most. Piatt and Macon County competitors also did well in this category. However, growers surpassing 90 bu./acre were scattered through most of the state, said Bob Wells, the ISA Yield Challenge coordinator.

Weather always plays a factor. This year, frequent high-yielder Bob Lakey didn’t make 100 bushels, Wells said. For the previous three years, Bob and Jason Lakey, of Champaign County, were the 100 bu. winners with 110.8 bu./acre in 2017; 105 in 2016; and 108 in 2015.

“This year he (Bob Lakey) just couldn’t crack it,” Wells said, noting that the winner was only about 10 miles away.

Some surprises

While noting that the yield winners are a small sample, Wells said a few of the variables didn’t turn out as expected.

For example, there wasn’t the expected yield boost from using both a fungicide and an insecticide.

“There was not as much bounce as we expected,” he said, and “there were no real differences in (crop) rotations.”

There didn’t seem to be a yield drag with continuous soybeans, as some expected.

Strip-till fields also didn’t yield as well as expected. However, Wells noted when it comes to farm profits, some tillage cost savings may make up for a little less yield.

While ISA’s yield challenge is a competition, most growers take part to find out what management practices might work best on their own farms to increase yields, Wells said. The side-by-side comparisons help farmers make some of those decisions.

In side-by-side comparisons, farmers have basic agronomy for their fields mastered and are looking at adding one or two practices that might help boost yield further, Davidson said.

Some of those comparisons this year featured noticeable differences between the check and the test. Brian Mansfield studied the impact of adding sulfur to his soybean fields near Woodson in Monroe County.

In his side-by-side study, Mansfield’s treated plot using Mesz Sulfur got about 9.2 bushels per acre more than the untreated plot, bringing the yield up from 76.4 to 85.7 bu./acre. But he cautions not to except that result with every sulfer additive.

“There’s a lot of differences in sulfur products, so do your research,” Mansfield told farmers at the soybean summit.

He said he spends a lot of time studying options before deciding what to try, but he believes it is worth the effort. He plans to use sulfur on his crop again this year and to test another possibility for yield improvement in the ISA’s challenge next year.

Phyllis Coulter is Northern Illinois field editor, writing for Illinois Farmer Today, Iowa Farmer Today and Missouri Farmer Today.