A fire Wednesday afternoon destroyed a building at the closed Summersun Nursery at 4100 E. College Way. Mount Vernon Fire Department Battalion Chief Mark Malone said the fire was reported at 3:26 p.m. and the first fire trucks arrived at 3:31 p.m. The building was not in use and had no power running to it. Firefighters from the cities of Mount Vernon and Burlington, and from Skagit County fire districts 9, 2, 4 and 3 responded to the fire. Burlington Fire Marshal Kelly Blaine is heading up the investigation to determine the cause of the fire. No injuries were reported.