Excessive levels of aflatoxin are showing up in early samples of many McLennan County farmers’ corn.

It’s a bad sign, farmers said this week as harvest time arrives.

Aflatoxin, a health threat to humans and animals who eat corn containing it, shows up in corn from plants that have been stressed while growing.

To test for aflatoxin, corn farmers use test rows such as this field near Moody. Poor yields and aflatoxin seem prevalent in western McLennan County, where some farmers may have to resort to crop insurance to cover losses.
Duane A. Laverty/Waco Tribune-Herald

Stresses can include high heat. Corn samples, tested at certain grain elevators set up to run the tests, must have less than 20 parts per billion aflatoxin levels from samples of grain pulled from farmers’ loads.

Corn with higher concentrations is unsafe and must be thrown out, not sold.

The main stress this year has been higher temperatures as the corn grew. Farmers in McLennan County are generally diversified, growing mostly corn, wheat and milo.

Milo crops seem to be OK, said Robert Cervenka, president of the McLennan County Farm Bureau. Still, in terms of revenues generated, corn is king and a weak crop is bad for local businesses.

How the crop is turning out depends on what part of the county the corn grew in, said Shane McLellan, county agriculture agent with the Texas ÅgriLife Extension Service.

Some areas got better weather conditions during the growing season than others. Heavy rains in late winter interfered with planting for many farmers, causing seed to be laid down several weeks late.

High temperatures, low rainfall

The late planting meant the corn was growing in higher temperatures later in the season. Rainfall also was lower than normal in some areas during the middle of the growing season.

In an area with little or no irrigation, corn is susceptible to heat and high heat causes the development of a fungus that produces the aflatoxin in the plants.

Test rows cut in farmers’ fields are signs that they are checking the aflatoxin levels.

Poor yields and aflatoxin seem prevalent in western McLennan County, where some farmers may have to resort to crop insurance to cover losses, McLellan said.

Aflatoxin is thought to be damaging to animal and human livers, including causing cancerous tumors.

Often, poor-yielding corn can be cut down for silage to feed to cattle, but for much less than selling a corn crop.

Corn with high levels of aflatoxin can only be plowed under.

Because corn fields were planted at different times as farmers dashed to plant between rains, the crop is coming in at different times depending on location, said Bennie Hargrove, who owns Circle H Grain, an elevator in Moody.

Good corn is still in the fields in some areas of the county and there is still be a chance for a decent crop, he said.

“The verdict is still out,” he said.

Farmer Rodney Schmalriede said rain at the wrong time has continued to be a problem even now.

His milo crop was just about ready for harvest when rains came and prompted additional “sucker heads” of the seeds they harvest to form on the plants. That also means he has to wait until the new heads ripen.

“This dadgum rain has really screwed us around this year,” Schmalriede said.

bteeter@wacotrib.com

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