On August 19, 1996, at 1515 central daylight time (cdt), a Cessna 180, N2814A, piloted by a private pilot, was substantially damaged when it collided with the water while maneuvering to avoid trees along the water's edge. The 14 CFR Part 91 personal flight was not operating on a flight plan. Visual meteorological conditions prevailed at the time of the accident. The pilot and passenger reported no injuries. The flight was departing Big Tamarack Lake, near Duxbury, Minnesota, at 1513 cdt. The pilot said the airplane lifted off the lake near its midpoint after extending 20 degrees of flaps. He said the airplane's stall horn was sounding as it flew about 20 feet above the water. The pilot said it was clear to him that the airplane would not clear the trees near the shoreline. The pilot said he turned the airplane to the left and reduced the power for landing. He said the airplane's left wing stalled and the airplane pitched down as it rolled left. The left wingtip, followed by the corresponding float, and fuselage collided with the water. The airplane sank shortly after coming to rest. The pilot was asked how many degrees of flaps for takeoff are recommended by the manufacturer. He said one notch, 10 degrees.