On September 16, 2005, about 1900 Alaska daylight time, a wheel-equipped Cessna 172 airplane, N124SM, sustained substantial damage when it collided with trees during the landing roll at a private airstrip, about 6 miles northwest of Anchorage, Alaska. The airplane was being operated as a visual flight rules (VFR) local area personal flight under Title 14, CFR Part 91, when the accident occurred. The airplane was operated by the pilot. The commercial certificated pilot, and the sole passenger, were not injured. Visual meteorological conditions prevailed in light rain. The flight originated at Merrill Field, Anchorage, about 1854, and no flight plan was filed, nor was one required. During a telephone conversation with the National Transportation Safety Board (NTSB) investigator-in-charge (IIC), on September 19, the pilot reported that he was landing toward the south on his grass-covered runway, which is about 1,700 feet long, and about 70 feet wide. He said his landing approach was high, that he landed long on wet grass, and skidded off the right side of the runway. The nose landing gear dug into the ground, and the airplane nosed over in an area of trees. It received damage to the propeller, left wing, and the right elevator.