Units from Solomons and St. Leonard were alerted to a single vehicle MVA. While en-route units were advised of single occupant and a pickup truck head-on into a tree with a subject being pulled out by bystanders. Crews arrived on scene to find the reported conditions. Chief 3 held command with company 3 units only. Ambulance 37 ground transported to Baltimore Shock Trauma due to helicopters being down to weather conditions. Units cleared in approximately 35 minutes.