The pilot was departing from a remote mountain lake in an amphibious float-equipped airplane. Prior to departure he observed the wind out of the east, and began his takeoff run in an easterly direction. He stated that the airplane was slow to accelerate and unstable once on the step. He closed the throttle and aborted the takeoff, the airplane immediately yawed to the right, he applied left rudder and deployed the water rudders in an effort to correct for the yaw, but the right wing impacted a tree and swung the airplane into the shoreline. The airplane sustained substantial damage to the right wing and right lift strut. The pilot stated that there were no preaccident mechanical anomalies with the airplane that would have precluded normal operation. While awaiting rescue, the pilot noted that the wind reversed direction about the center of the lake, and he may have encountered a tailwind during the takeoff run. In the recommendation section of the NTSB Accident/Incident Reporting Form 6120.1, the pilot stated that the accident may have been avoided if he had made the decision to abort the takeoff sooner.