On May 21, 1994, approximately 1630 Pacific daylight time, N50WS, a Grumman G-164B AgCat, was destroyed when it collided with trees while conducting aerial application activities about three miles south of Princeton, Idaho. The commercial pilot, who was the sole occupant, received minor injuries and was doused with Parathion. There was no flight plan for the flight, which originated at Pullman, Washington about 1558. Visual meteorological conditions prevailed and no ELT was installed in the aircraft. The pilot stated that he had made twelve previous rounds bordering the field. During a pull-up maneuver, after reaching for the flow shutoff valve, his sleeve caught the throttle and pulled it to idle. He attempted to recover power by opening the throttle, but the engine coughed and he was unable to regain power before impacting the trees. He also attempted to jettison the spray agent at the last minute, but was unsuccessful.