N5826V

After being towed to altitude, the pilot of the glider began soaring above a mountain peak. After making several circular passes over the peak the glider began to descend, and the pilot initiated a turn to an adjacent ridge. As he passed over the ridge, he felt the glider sink and he initiated a descending right turn. During the turn, the pilot felt the glider "jolt" and yaw to the left. He verified that the flight controls functioned correctly, and initiated an uneventful straight-in approach and landing at the departure airport. Postaccident inspection revealed damage consistent with an in-flight collision with a tree. The glider sustained substantial damage to the left wing spar and aileron during the collision.