The pilot of the tailwheel equipped airplane reported that during takeoff from a tidal flat, a strong quartering tailwind gust "hit the tail" and he corrected with rudder. The pilot further reported that as soon as the airplane became airborne another strong quartering tailwind gust pushed the airplane inline to impact a driftwood tree that was lying on the tidal flat. The airplane proceeded to strike and bounce off of the driftwood tree and then descended toward a water channel. The pilot reported that he "did not know exactly what happened", other than the airplane touched down on the other side of the water channel and the main landing gear collapsed. Subsequently, the left wingtip hit the ground and the airplane slid to a stop backwards. The pilot reported that there were no pre impact mechanical failures or malfunctions with the airframe or engine that would have precluded normal operation.