WHILE evaluating corn plants for young 4-H'ers earlier this summer, one of those "teachable moments" popped up unexpectedly. One cornstalk a young 4-H'er proudly presented looked OK, except for a noticeable insect hole in the lower stem, just at the right height where stalks break over in the fall. The insect was long gone, but it was time to explain secondary infections. The 4-H'ers learned that insects can form entry points for disease, just like cuts on the body make it easier for bacteria to enter. This plant, with its perfectly round insect hole, would be a sitting duck for organisms that cause stalk rot.
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