On August 7, approximately 1100 mountain daylight time, a Piper PA-28-140, N4372J, registered to and operated by the pilot, was substantially damaged during takeoff from a grass airstrip near Glenwood, New Mexico. Visual meteorological conditions prevailed at the time of the accident. The personal flight was being conducted under the provisions of Title 14 Code of Federal Regulations (CFR) Part 91 without a flight plan. The pilot, the sole occupant on board, was not injured. The cross-country flight originated at Negrito, New Mexico, and was destined for Beaverhead Airstrip near Glenwood. The pilot said he was doing some back country flying and landed to the northeast at what he thought was Beaverhead Airstrip. It was actually Shepley Ranch Airstrip, elevation 7,400 feet mean sea level. The field was not maintained and there was tall grass along the runway. The pilot turned around and took off to the southwest. The airplane failed to gain altitude and collided with a fence and impacted terrain. The pilot said the temperature was 26 degrees Celsius (79 degrees Fahrenheit). Flight control continuity was confirmed and no anomalies were found with the airplane.