On April 6, 2005, about 1400 Pacific daylight time, a homebuilt Park Kitfox IV, N70265, registered to and flown by the pilot as a 14 CFR Part 91 personal flight, experienced a partial power loss shortly after takeoff from Beagle Sky Ranch, Eagle Point, Oregon. An emergency, off airport, landing was made to a field south of the airstrip. During the landing roll, the aircraft collided with terrain and the nose wheel collapsed. Visual meteorological conditions prevailed at the time and no flight plan was filed. The aircraft was substantially damaged and the private pilot, the sole occupant, received minor injuries. During a telephone interview, the pilot reported that he took off to the south. Shortly after take off, about 150 feet above ground level, the engine lost partial power. The airplane was unable to maintain altitude, and the pilot initiated an off airport emergency landing to an open field. During the landing roll, the nose gear collapsed when the pilot tried to maneuver away from obstructions. The pilot further reported that this was the first flight after the airplane had been setting for about three months with the fuel tanks only partially full. The pilot stated that he had accumulated about ten hours of flight time since he purchased this aircraft. During an inspection of the airframe and engine by a Federal Aviation Administration Inspector from the Hillsboro, Oregon, Flight Standards District Office, no evidence of a mechanical failure or malfunction was found.