At 1530 eastern time, a Cessna 172N was damaged when it collided with trees during takeoff from Simpson Airport in Philippi. The pilot and pilot-rated passenger were not injured. According to the pilot, he performed a short-field takeoff from runway 19 at Simpson. He rotated the airplane about 1,300 feet from the approach end of the 1,500-foot long turf runway. During the initial climb out, the airplane impacted the tops of 40-foot-tall trees, located about 200 feet from the departure end of the runway. The airplane descended through the trees, coming to rest inverted and suspended in a tree. The pilot stated that he was aware of the trees prior to takeoff. The weather station at Clarksburg, W. Va., 10 miles away was reporting wind from 340 degrees at six knots and a temperature of 46 degrees F. Interpolation of the takeoff distance chart in the Cessna 172N Pilots Operating Handbook revealed that at a weight of 2100 lbs, 1,000 feet pressure altitude, temperature of 10 degrees Celsius, and a tailwind component of five knots, the calculated takeoff distance required was 1,685 feet for operations on a dry, grass runway.