Watch for ear molds in 2011
Fusarium ear mold. Fusarium ear mold is caused by the fungus Fusarium verticillioides and other Fusarium species. The fungus survives on crop residue, and infection occurs primarily through silks and insect damage. While symptoms can appear under a wide range of conditions, they are most severe when weather is hot and dry.
A corn ear infected with Fusarium ear mold. Symptoms include a distinct "starburst" pattern of streaks radiating from the tops of kernels and close to the ear tips. Signs of the fungus include cottony fungal growth that ranges from white to pink.
Some Fusarium species produce mycotoxins called fumonisins, which can be toxic or even fatal to livestock.
Disease control includes planting disease-tolerant hybrids, rotating crops, managing residue, and controlling insects through Bt traits.
I have ear mold--what can I do? Unfortunately, once mycotoxins are present in grain, they are not broken down by the drying process, but there are several actions you can take to stop their production. Start with clean grain bins, and store contaminated grain separately. Set your combine to kick out light kernels, and clean grain before storage. If you anticipate large-scale infection, harvest at higher moisture levels (25%), and dry at high temperatures--to 18% moisture for short-term storage and 15% for long-term storage--as soon as possible to stop fungal growth and the potential for additional mycotoxin production. If you suspect Aspergillus ear mold, dry grain to 14%. After drying, cool grain to 30°F as soon as possible to retard fungal growth.
Test your grain to get an accurate measurement of the mycotoxin concentration. This will help in determining how the grain can be used. Contact the Illinois Department of Agriculture's Centralia Animal Disease Laboratory for mycotoxin testing.