The pilot was making a clean-up pass at the south end of a field during an aerial application flight when the accident occurred. A 30-foot tall power line ran north and south through the middle of the field. The pilot stated he was paying attention to the trees along the south end of the field during the pass when he realized that he was approaching the wires. He was unable to climb over the wires so he decided to fly under them. In doing so, the airplane contacted the corn which was 7 feet high and the airplane was pulled down into the field. Substantial damage resulted to the lower wings and the main landing gear mounting truss.