On August 12, 2004, about 1000 central daylight time, an Air Tractor, AT-301, N2353W, operated by a commercial pilot, sustained substantial damage on impact with a tree and terrain during initial climb from a private airport near Cambridge, Kansas. The aerial application flight was operating under 14 CFR Part 137. Visual meteorological conditions prevailed at the time of the accident. No flight plan was on file. The pilot reported minor injuries. The local flight was originating at the time of the accident. The pilot's accident report stated: When I first powered up the engine, I thought it seemed a bit rough running, but soon it straightened up. I looked down, at the manifold pressure to see if the blower was producing, and it was at 36 inches, which was normal for this aircraft. At this point, I concluded that the engine was okay and seemed to be producing adequate power. The takeoff roll was as I had expected, with rotation and liftoff at about the point it should have been. Then, the AT 301 seemed to settle back to the runway, with the tail wheel hitting first, which put the main gear back on the runway. With this bounce the AT 301 went back into the air, and I thought I was going to carry the load on out. There was no time left at this point to shut down, and I thought it was going to fly. Just after crossing the end of the runway, the plane lost altitude with the left wing catching a tree, which tore off the left aileron and immediately put me on the ground, hitting with the left wing and engine first. The impact spun the aircraft around counterclockwise. The tail hit and the engine came off, which passed through the left wing, severing about 5 - 6 feet off. The plane skidded backwards about 50 feet to a stop, crumpling the tail section. I received minor injuries, and was fully aware during the entire flight. A Federal Aviation Administration Inspector performed an on-scene examination of the wreckage. No pre-impact anomalies were detected during that examination. The pilot's safety recommendation stated: If I had an engine analyzer which could have told of a cylinder that was not up to standard - there would not have been any take off attempted. From now on any ag aircraft I fly I will have my left hand resting on the dump on take off.