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CMPM offers advice for farmers dealing with mycotoxins

EAST LANSING, MI -- As harvest continues, the Corn Marketing Program of Michigan (CMPM) has received some reports of farmers encountering vomitoxin in their corn crop. To assist, CMPM has compiled some expert viewpoints for farmers dealing with this issue, from coping in the field, to insurance concerns, to marketing your corn.

Dealing with Infested Fields and Contaminated Grain in 2016 and Beyond - Martin Chilvers, Field Crops Pathologist, Michigan State University

• Mycotoxins such as deoxynivalenol (DON, sometimes called vomitoxin) are produced by fungi which require moisture for growth. Fields with ear mold disease should be harvested as soon as possible and dried quickly to minimize mycotoxin accumulation.

• To determine if the field is infested with ear mold visit five points throughout the field and pull the husks all the way back on 20 ears, for 100 ears per field. Examine the entire ear for ear rot and use a guide to aid in diagnosis. If unable to identify the ear mold, a sample including the entire ear can be sent to the MSU diagnostic clinic (

• Gibberella ear rot and Fusarium ear rot appear to be the primary ear rots of concern in Michigan, though others can and do occur. Insects can also play a role, including western bean cutworm which can result in wounds for potential fungal infection.

• Fields with a history of ear rot disease should be planted with hybrids that are less susceptible. Corn should be grown under conditions that promote healthy plants and minimize insect damage. Fungicides such as Proline are labelled for suppression of ear mold, but application timing is critical.

• Fields that are identified to have ear mold should be harvested early and the grain should be segregated. During harvest, combine adjustments can be made to discard lightweight diseased kernels and fines. Grain moisture should be lowered as quickly as possible to less than 15 percent.

• For long term grain storage, moisture should be brought down below 13 percent and grain cooled to 30°F. Grain should be tested for mycotoxins when fields with ear rot problems are detected.

• Coring the grain bin can improve storage airflow and remove fines. These fines may contain a higher amount of DON, thus not being representative of the entire bin.

• Corn disease management guides are freely available for download as part of the Crop Protection Network at

Managing Crop Insurance when Vomitoxins are Present – Todd Davis, Spartan Insurance Agency

If a grower suspects that he/she may have an issue and have crop insurance, they should contact their agent immediately and have a harvest loss setup. The adjustor will contact the grower and discuss sampling options. The samples must be evaluated by a Federal Grain Grader. If delivering grain directly to a disinterested third party, samples obtained by the buyer can be used by the adjustor.

If the grain is stored in on-farm storage, additional damage that occurs in storage is not covered by the Multi-Peril Crop Policy. Therefore, it is important that if a grower has on-farm storage that the samples be taken immediately by the adjustor. Samples taken by the grower are not acceptable.

Options from that point will be different for each grower. Every car accident is different and so is every crop insurance claim. Multiple factors may determine if a claim is paid, including type of coverage, coverage level, aph, yield and vomitoxin levels.

The number one best step for a grower is to notify their agent as soon as there is a suspected issue and have continued communication with their adjustor so that the claim can be handled appropriately.

Marketing Your Corn When Mycotoxins are Detected in the Market – Gabe Corey, Plant Manager, Carbon Green BioEnergy

There are a lot of factors that go into marketing corn. It’s important for farmers to remember that just because mycotoxins have been detected, it doesn’t mean that your corn can’t be marketed. Here are some factors to keep in mind:

• There have been reports of mycotoxins in corn all over the eastern corn belt, from Iowa to Michigan. There’s a lot of variability, with growers reporting everything from below 1 ppm up to 15 ppm.

• We can’t always predict what the market will look like. Yes, there are mycotoxins in the market. However, the market still has to use corn. That could mean that there will be maximum levels allowed or that corn will be discounted for certain end-users.

• Make sure you know what you have. That means getting representative samples of your grain so that you have a clear picture of the levels you’re dealing with.

• Talk to multiple end-users and elevators so that you understand what your options are. Don’t assume that just because one marketer won’t take your corn that you’re out of luck.

The market is always changing and it can be challenging to adapt to mycotoxin issues, but if you do your homework it’s still possible to successfully market your corn.