How a challenging season resulted in good yields
Nov. 28, 2022
The goal of the Corn Watch project, sponsored by Seed Genetics Direct, is to study the growing season through the lens of one cornfield in the Corn Belt. The field under the microscope this year was in south-central Indiana. Following the journey in this field uncovers insights that should be valuable no matter where a farmer lives or the kind of soil on the farm.
The Corn Watch ’22 field was planted May 11 on silty clay loam soils (soil that contains 27 to 40 percent clay and less than 20 percent sand.). The field is pattern-tiled without irrigation. About 200 pounds per acre of nitrogen were applied with the final increment at planting.
“It was an up-and-down season, but it turned out well,” said Dave Nanda, director of genetics for Seed Genetics Direct. “Yield performance here is a testament to the advances plant breeders have made in developing hybrids to withstand heat and drought stress.
“There are still advancements to be made, including producing hybrids that allow ears to droop in the fall, making ear mold less likely, but yield results speak for themselves.”
What was that yield? At 15.5 percent moisture, the grower reported an average yield of 236.7 bushels per acre. The following brief replay explains why:
Warmer-than-normal May weather helped the Corn Watch ’22 field get off to a fast start. The crop was out of the ground in seven days and at V5 by 35 days.
Quick start. Emergence in the 2021 Corn Watch field was spread over three weeks. In 2022, emergence was 96 to 98 percent complete in less than two days!
“Weather conditions were the biggest difference,” Nanda said . “In 2021, it turned cool and wet after planting during the last week of April. This year, the week after planting featured near record-high temperatures.”
There were still a few stragglers, which resulted in occasional late-emerging plants with nubbins at harvest. However, they were few and far between.
Challenging drought conditions. The heart of the growing season turned hot and dry quickly. This field received just slightly more than two inches of rain total for June and July combined. The U.S. Drought Monitor declared the area “abnormally dry” and then later placed it in drought. Some areas received relief in early July, but rain skipped this field.
“Plants were developing the gray cast that comes with severe stress, especially on eroded areas,” Nanda recalled. “When I visited on July 7, yield prospects were dimming quickly.”
Saved by rain, cooler weather. Rain returned in earnest beginning Aug. 1 and the field received more than 7 inches of rain through mid-September.
“The crop here took a hit from hot, dry weather during pollination, but we believed that if conditions were good during grain fill, yield would still be more than 200 bushels per acre,” Nanda said. “Our mid-September yield checks put it at 220 to 230 bushels per acre.”
However, near black layer, the field still wasn’t home-free.
“These hybrids held their ears upright because the peduncle — the plant part connecting ear to stalk — was short,” Nanda explained. “Ear mold set up by stress flourished. Upright ears are more conducive to ear rot because they hold more moisture.”
When the combine went through the Corm Watch 22 field, the average yield for the entire field was slightly higher than estimated in September.
But by harvest, ear molds weren’t advancing. On many ears, signs of mold were negligible. Nanda suspected this was because the weather turned bone-dry in late September, arresting mold growth.
Final analysis. “Final yield exceeded our expectations,” Nanda said. “Grain fill was better than anticipated. and kernels were deep with less tip abortion than expected.”
The Corn Watch ‘22 field is sponsored by Seed Genetics Direct for Farm Progress. The project focuses on one field in central Indiana and uses observations of that crop to help growers make applications to their own farm. Stories are written by Tom Bechman.