Open up your corn and find a little surprise? Organically grown corn has a pest that many farmers and consumers have learned to live with. Understanding the growing and handling of fresh-picked, organic sweet corn just may increase your appreciation of this summer treat.
Adult corn earworm moths lay eggs on the silks of young corn ears. The caterpillars hatch and crawl down the silk channel into the ear of corn and feed on the silk and the small corn kernels. In the South, the corn earworm overwinters and becomes active early in the growing season, but in the North, migratory flights bring large numbers into a region, usually invading corn later in the season.
Natural predators of the corn earworm eggs and larvae include ladybird beetles, lacewings, parasitic flies and wasps. Currently, there are few organically approved methods to eliminate corn earworm damage. To reduce the damage done by the corn earworm, organic growers have used vegetable or mineral oil and the bacterial pathogen, Bacillus thuringiensis (Bt), toxic only to caterpillars. Several drops of the oil/Bt mixture is applied directly to the tip of the young ear, where the caterpillars enter. If the caterpillars feed on the oil, they will die. Using this method, the grower has a short window in which to apply the pest control, and it is also rarely 100% effective.
Many stores have accepted the fact that organic corn will have some corn earworm damage. They simply cut off the tip of the corn as soon as it is delivered, then put it out for sale. This is the best way to store your fresh picked organic sweet corn at home too – check for caterpillars and cut off the tip of each ear before placing it into the refrigerator. It is important to take a look at the tip to make sure you have taken off enough and have not left the worm there.
Sweet corn is sweetest just after it has been picked, so you may want to use corn right away if it is possible. If you do need to store it, keep the husk on the corn until you are ready to use it – it will stay fresher.