DYER BROOK, Maine — An electrical short circuit in a lawn tractor stored in a garage at Southern Aroostook Community School is the likely cause of a fire that closed the school to students for the day on Wednesday. The buildings and grounds crew discovered one of the school’s tractors on fire in the garage bay shortly after arriving for work at 5:30 a.m., RSU 50 Superintendent Jon Porter said Wednesday morning. The crew grabbed fire extinguishers and used a wash bay hose to prevent flames from spreading, and their quick action kept the damage from being much worse, Porter said. he inside of the work bay at Southern Aroostook Community School shows how the walls and ceiling were scorched by an early morning fire at the school.