According to the sport pilot, while turning from the left base to the final leg of the approach for runway 2, with engine power reduced to "near" idle, a gust of wind came from the right and the airplane lost altitude. He attempted to recover the altitude loss by rolling the airplane to a wing level attitude and adding full power; however, the airplane impacted the top of a tree. The airplane subsequently impacted the ground in a nose-down attitude. A postaccident examination by a Federal Aviation Administration inspector revealed that the wings, fuselage, and tail section were substantially damaged. The pilot reported no pre-impact mechanical malfunctions or abnormalities that would have precluded normal operation. Around the time of the accident, the wind at the airport was from 020 degrees at 12 knots with gust to 19 knots.