Give corn wet feet, sun on its tassels and cool, nighttime summer temperatures and you'll likely be talking about record yields. That's part of the reason for two consecutive years of record corn yields in North Carolina, says the state's corn specialist. But the reason goes much deeper than ideal growing conditions.
“Farmers are doing a better job of managing corn on acres best suited to growing the crop,” says Ron Heiniger, North Carolina State University Extension corn specialist.
The result is another corn yield record — made even before the ink on the last one was dry from last year. In 2001, the yield of 122 bushels per acre sets a new state record, according to Donald Buysse, ag statistician with the North Carolina Department of Agriculture and Consumer Services Ag Statistics Division. A yield of 116 bushels per acre set the previous mark in 2000.
The records come at a time when corn acreage in North Carolina is declining. On average, corn yields in North Carolina have been in the upper 80-bushels-per-acre range.
“We had good climate, sure, but the record is also tied to two other factors,” Heiniger says. “Farmers are getting those riskier acres into cotton or soybean production and moving corn to the more productive areas of the farm.”
In addition, farmers are applying nitrogen earlier in the season and selecting hybrids for heat tolerance, Heiniger says. “When growers do a good job of selecting hybrids and targeting them on their better soils, we can raise good corn in this state.
“There are a number of things that came together to make those high yields possible,” Heiniger says.
Heat and moisture stress generally hold back yields in North Carolina. “The saying, ‘You're two weeks away from a drought in North Carolina is really true,” Heiniger says.
Last year, producers were hardly two weeks away from the next rain during the critical pollination period for corn.
Dry weather in late April and May when the crop was at the four- and five-leaf stage let the corn establish deep roots. Consistent rains — even a little above average — from mid-May through early July provided excellent growing conditions through the critical silking stage.
Temperatures were in the 90s during the day, and between 55 degrees Fahrenheit to 85 degrees Fahrenheit at night. “The best corn is grown when it has wet feet and its head is in the sun,” Heiniger says. “That's what we had this year: Plenty of moisture and sunshine during the day and cool nights.”
In order to manufacture starch and put on large kernels, corn has to respire or breathe at night, hence the importance of summer nighttime temperatures lower than 85 degrees F. “Oftentimes, we don't get nighttime temperatures into the low 80s in the middle of the summer, especially on the North Carolina coast,” Heiniger says. “High yields in the U.S. generally come from the Great Plains, where they can irrigate and where nighttime temperatures are cool. That's what happened here in North Carolina this year.”
Some of the biggest corn yields in North Carolina came from the Piedmont region, a fact Heiniger attributes to the higher elevations and cooler nights. Generally, the higher yields occur on the coast, where the productive soils are more conducive to growing corn.
“There are some good lessons to be learned from the successes over the last two years,” Heiniger says. “To make a profit growing corn, producers must plant corn on their best land and select management practices best suited to the soils and the environment on their farm. These records represent the impact of the grower making the right decisions.”