Will heat spell spoil record corn crop?
USDA predicts another record, but looks can be deceiving
Iowa’s corn crop — a record, according to U.S. Department of Agriculture projections — may not be as good as it looks, farmers and agronomists say.
Admiring field after uniform field of tall, lush stalks sporting club-like ears, Gov. Terry Branstad, on a conservation tour in early August, was among many Iowans who said they had never seen the state’s crops looking better.
“It really does look good — most say the best they ever saw,” said Iowa Agriculture Secretary Bill Northey, who also has traveled the state extensively recently.
The USDA, in its monthly outlook Friday, pegged Iowa’s average corn yield at 197 bushels per acre, well above the state’s record yield of 192 bushels per acre established last year. The agency also predicted a record Iowa soybean yield, 57 bushels per acre, up half a bushel from last year’s record yield.
“But looks can be deceiving,” said Iowa State University Extension agronomist Mark Licht, an expert on corn production.
Licht said he has been getting “mixed signals” from field agronomists in different sections of the state as well as from yield forecast projections conducted by ISU and the University of Nebraska.
“The crops look absolutely gorgeous from the road, but when you pull back the husk, the ear doesn’t measure up to last year,” said Meaghan Anderson, an ISU Extension agronomist whose 15-county territory includes Linn and Johnson counties.
“Right now, I would say it’s going to be a good crop but not a record crop,” Licht said. “We are going to see some very good yields and some that we will be less than thrilled to see.”
Virgil Schmitt, an extension agronomist in Eastern Iowa, said hot days and warm nights in July and August robbed the 2016 crop of its full yield potential.
The excessive heat, he said, “is rushing the crop along, and we would like for that not to happen.”
Cooler weather results in an extended grain fill period, yielding larger ears and heavier test weights, he said.
Tracy Franck, whose family farms 2,400 acres in Buchanan County, said he noticed the same thing last week when he went into some of his fields to assess his crops.
Franck, whose corn averaged more than 200 bushels per acre last year — his best yield ever — said he thought this year’s crop would surpass it until he took a closer look.
“The ear size was way small. I was really disappointed. It’s the heat is what it is,” he said.
The statewide average high temperature for June and July, 83.7 degrees, was just 0.6 degree warmer than normal, but the average low during that period was 2 degrees warmer than normal, according to State Climatologist Harry Hillaker. The summer’s hottest weather occurred in June, when Cedar Rapids recorded five days with high temperatures in the 90s and Iowa City recorded nine.
Grant Kimberley, director of market development for the Iowa Soybean Association, said it remains to be seen if this season’s corn crop breaks records.
“There is no doubt it is good. It will take combines with yield monitors to figure out if it is record good,” said Kimberley, whose crops near Ankeny suffered from a lengthy dry spell in June.
Northey said he, too, is withholding judgment on the crop until harvest.
Despite southern Iowa’s hot, dry June, Iowa Corn Growers Association President-elect Kurt Hora, who farms 1,700 acres north of Washington, said he thinks “we still have the potential to have our best crop ever.”
Hora credits advances in seed corn genetics with helping his corn weather the heat and drought stress that rolled its leaves in June. “Rain arrived before pollination, and the corn really bounced back,” he said.
Roger Lansky, who grows corn on 2,900 acres near New Hampton, said he anticipates his best crop ever.
Besides timely rains and seed corn advances, Lansky credits farmers themselves with eliminating many weak spots in their fields.
With the advent of combine yield monitors, farmers have been able to pinpoint portions of fields with consistently low yields, he said.
In the case of wet spots, they are installing tile drainage to make them more productive, and they are employing cover crops and other methods to increase organic matter and improve the fertility and water storage of light soils that tend to dry out quickly, he said.
Northey said uniformity is a hallmark of the 2016 corn crop. In many parts of the state, he said, rainfall was sufficient to adequately water the light sandy soil but not so heavy it drowned out the darker, heavier soil.
“There are very few zeros out there,” he said.