Stressed Corn Crop Vulnerable to Rare Toxins;

Danger to livestock from the corn's use in feed usuallly is confined to Southern states.

Recent rains have bolstered area corn that survived the drought, but the crop still may be susceptible to dangerous toxins that have the potential to kill livestock and further limit yields expected to be among the lowest in years.

Aflatoxins are produced by mold fungi that can grow on corn and be fatal or harmful to animals that ingest them in high concentrations. Usually the toxins are found at harvest time in corn produced in southern states, but crop experts are concerned the hot, dry weather has moved the danger line farther north.

"It's going to take a really unique year if we're going to see it here, and we're having that unique year," said Joe Lauer, an agronomy professor at UW-Madison.

Lauer said farmers also need to be on the lookout at harvest time for toxins from another genus of fungi called Fusarium. Those toxins can cause milking cows to become less productive and can induce farm animal miscarriages if ingested in high enough concentrations.

"It's not a good situation. It's certainly something people should be wary of and watch for," said Lauer, who added it's too early to make any predictions because the toxins aren't produced until around harvest time, which is at least two months away.

"Even though we might have molds and the pathogens are out there, that doesn't mean the chemical will be produced or the toxins will be produced," Lauer said. "That hinges on very specific environmental conditions, which we haven't had yet."

Aflatoxins, which are produced by the Aspergillus fungi and can be recognized by yellow-green or gray-green mold on corn kernels, do well in hot and dry conditions through September and October. Fusarium fungi produce the toxins primarily when cool and wet conditions combine with wild temperature swings in the fall.

Mark Mayer, the ag agent for the Green County UW-Extension, said he saw aflatoxins in Wisconsin corn during the 1988 drought, which many have compared to this year's drought. "So the potential is there," Mayer said. "We just don't know at this point. Farmers need to be aware that it could be an issue."

So do grain purchasers such as ethanol plants, which can't use corn with aflatoxins partly because they can become concentrated in the animal feeds the plants also produce.

"I've got concern over it," said Dan Wegner, the commodities manager at United Wisconsin Grain Producers, which runs an ethanol plant in Friesland. "But I've been in the grain industry for over 20 years and I've never seen it this far north. You see it, but not at levels that are problematic. I think our evenings get cool enough where it helps" stop the toxins.

Lauer said corn with Fusarium toxins can be used for feed if blended with enough good corn. But he added farmers won't get as much money for the corn and will have to spend more for better corn for the blend.

Lauer knows farmers are stressed by the drought and doesn't want to create more bad news. "People throw up these flags all the time and get people get worried for no reason," he said. "I'm not trying to pooh-pooh this. I'm just trying to be realistic."