The private certificated pilot was departing from a remote area that was about 900 feet long on a Title 14, CFR Part 91, local area personal flight. The pilot reported that he previously had trouble with the airplane's charging system. When he attempted to start the airplane for takeoff, the battery was dead. He placed the magneto switch on the left magneto to facilitate starting, and hand-propped the engine. He then began the takeoff roll, which was longer than he expected. In order to miss trees at the end of the departure area, the pilot applied left rudder to maneuver past the trees, but the right horizontal stabilizer and right elevator collided with high brush. The airplane became airborne, and the pilot continued to his destination, about 8 miles away. Upon landing, the pilot discovered substantial damage to the stabilizer and elevator. The pilot reported that he also discovered that the magneto switch was still on the left magneto position, and that he did not select the "both" magneto position prior to the takeoff, thereby reducing available engine power.