The pilot reported that while decelerating during the landing roll on a grass runway the nose gear began to skid. The pilot further reported that the nose gear impacted an ant hill, which resulted in a nose over and substantial damage to the fuselage and empennage

The pilot reported there were no preimpact mechanical failures or malfunctions with the airframe or engine that would have precluded normal operation.

After the accident, the pilot reported that the tolerance between the nose wheel tire and fairing was estimated to be 1/4". The pilot further reported that there was debris build up in the back of the nose gear fairing and that during a postaccident check the nose gear was not able to rotate as freely as the main landing gears.