The crash happened Saturday around 11 p.m. on Wallace Lake Rd. -- west of N. Poplar Rd in the town of Trenton.When authorities arrived on the scene, the man was found lying in a ditch with a severe head injury.
He was the only one on the motorcycle and was not wearing a helmet.
Police's investigation revealed he was ejected from the motorcycle after striking a deer.
The deer is believed to be the only contributing factor to the accident. The man's current condition is unknown.