The two commercial pilots reported that the purpose of the flight was to identify suitable emergency landing sites in the area. A small private airport was located, and they decided to make a landing. The right seat pilot took control and made a low pass over the runway and discovered piles of gravel blocking half the width of the runway. He decided to attempt a short field landing. While maneuvering for landing, the airplane was in a left bank turn when the wing collided with a tree. The pilot applied rudder control and thought about going around but decided against it due to trees blocking the runway. The airplane was put into a left wing down slip as he tried to keep the airplane as level as possible. The airplane touched down on the right-side landing gear and the right wing dug into the dirt. The airplane subsequently came to rest inverted. During the accident sequence the airplane sustained substantial damage to the fuselage, empennage and wing. The pilot reported that there were no preaccident mechanical failures or malfunctions with the airplane or engine that would have precluded normal operation. Neither pilot submitted the National Transportation Safety Board Pilot/Operator Aircraft Accident/Incident Form 6120.1.