It is possible to find high-oil corn (HOC) varieties that kick out premium-earning oil levels without taking a hit on yields. But it takes some digging. And performance may not be consistent.
Since 1997, Ohio State University (OSU) has tested varieties in the Top Cross (TC Blend) grain production system with both high levels of kernel oil and yield potential similar to normal corn hybrids. The Top Cross system is licensed by DuPont Specialty Grains.
In 2000, OSU researchers compared six TC Blend varieties with the conventional counterparts of two of the TC Blend entries. They conducted the testing at South Charleston and Hoytville.
“At South Charleston, most of the TC Blends produced yields that were equal to or not significantly different from the highest-yielding check hybrids,” reports Peter Thomison, OSU agronomist. “Yields ranged from 147 to 156 bu/acre.”
It was a different yield story at Hoytville, however. Those same TC Blends averaged 13 bu/acre less than the two check hybrids.
“We have seen these types of yield differences, by location, in the past and don't have an entirely satisfactory explanation yet,” says Thomison. “There could be several factors at work and we are trying to sort them out.”
There were significant differences in grain oil content among the six TC Blends at each location, Thomison notes. They ranged from 6.4% to 8.1% at South Charleston and 6.4% to 7.5% at Hoytville.
Conventional hybrids averaged 4.3% oil at South Charleston and 3.8% at Hoytville.
Farmer and crop consultant John Kapraun, Rochelle, IL, also has seen a wide range in performance among HOC varieties. Kapraun, who grows HOC, says most HOC varieties have yielded about 3-4 bu/acre less than conventional corn on his farm, although a few have yielded more.
“In my experience, there have been only a limited number of high-oil varieties that have both relatively high yield and high oil content,” Kapraun notes. “That means farmers need to be very selective in what they grow.”
Kapraun has an annual test plot on which he screens high-oil varieties. In 2000, his highest-yielding HOC was Pfister 2680-19. It produced 183 bu/acre and averaged 7.9% oil.
But the incentive for HOC has been going downhill, he says.
“When we began growing high-oil corn in 1996, the premiums were good,” Kapraun reports. “We started out getting a full 30¢/bu premium for 7.5% oil. Then the buyers raised the minimum oil content to 8%. Next, they dropped the premium to 25¢. Now it's down to 22¢ for 8% oil.
“Currently, assuming we get decent yields, we can make about $10/acre more net profit with high-oil corn than with conventional corn. However, if the premium drops another 5¢, I will quit raising high-oil,” he says. “It won't be worth it at that point due to the extra work of finding varieties that have a combination of yield, oil content and test weight.”