On March 18, 1998 at 1800 hours Pacific standard time, an Ayers S2R, N32064, struck power lines while maneuvering underneath them, and made an emergency landing in an open field near Willows, California. The aircraft, operated by Willows Flying Service under 14 CFR Part 137 as an agricultural crop dusting operation, sustained substantial damage. The commercial rated pilot, the sole occupant, was not injured. Visual meteorological conditions existed and no flight plan was filed. The flight originated from a private airstrip. The pilot reported that he was taking a load out to an alfalfa field for spraying, and did not maintain clearance with wires that he was attempting to maneuver the aircraft under. The rudder was torn off after the aircraft struck power lines. The aircraft entered a continuous right turn after the loss of the rudder. The pilot then flew over a large open field, reduced power, and landed without further incident. A Federal Aviation Administration inspector from the Sacramento, California, Flight Standards District Office examined the aircraft on-scene. No other anomalies were noted with the aircraft.