RIVERHEAD - A powerful storm that swept through the region Monday flattened a corn maze located on a Riverhead farm. "It's like buying a new car and having an accident, you get frustrated," says farmer Jim Zilnicki.In the 80 years his family has owned the farm, Zilnicki says he's never seen anything like Monday's storm, which not only destroyed the maze that used to bring in some $5,000-$6,000 a year, but also some irrigation equipment.The National Weather Service believes that what may have caused the corn maze to topple was a microburst -- an inverse tornado where strong downdrafts cause damaging winds on and near the ground. Zilnicki still hopes that the sun will help his corn stalks straighten up, allowing him to salvage the maze.