The pilot landed the ski-equipped airplane on the snow-covered frozen lake earlier in the day. After several hours of ice fishing, he taxied the airplane to the east side of the lake for departure. The lake's longest axis (east/west) was approximately 2,000 feet long. The pilot reported that the lake's orientation, terrain gradient, shoreline trees, and prevailing winds favored a departure to the west. During the takeoff run, the airplane accelerated slower than normal due to a slush layer that had formed since the previous landing. The pilot reported that the tail became airborne about halfway across the lake, but he aborted the takeoff when the airplane had not attained flying airspeed after crossing 3/4 of the lake. The airplane was unable to stop before running aground and impacting several trees, substantially damaging the fuselage and both wings.