On August 12, 2008, at 1730 central daylight time, an Air Tractor AT-401, N45029, collided with the terrain during an off airport forced landing in Ida Grove, Iowa. The commercial pilot was not injured. The airplane received substantial damage to both wings and the aft fuselage. The aerial application flight was operating under Title 14 Code of Federal Regulations Part 137. Visual meteorological conditions prevailed and no flight plan was filed. The flight departed the Ida Grove Municipal Airport (IDG), Ida Grove, Iowa, just prior to the accident. The pilot stated that the engine was producing 36 inches of manifold pressure and 2,250 rpm during the initial takeoff. Shortly after takeoff, he noticed the airplane was not climbing and the manifold pressure dropped to 28 inches or less. The pilot landed the airplane in a soybean field and after a ground roll of about 100 feet, the airplane contacted an embankment. The airplane twisted to the right and became airborne for a distance of approximately 100 feet prior to contacting the terrain and sliding to a stop. Post accident inspection of the airplane revealed the turbocharger blower had failed.