A large brush fire in Dedham sent a thick plume of black smoke over the Boston area Thursday evening. Deputy Fire Chief Donald Beltis said the blaze was in the Fowl Meadow. He said there were no injuries, but he did not know exactly how many acres had burned. An initial call for the fire came in at 5:50 p.m., Beltis said, and crews had it under control by around 9 p.m. He said firefighters did not have to help residents evacuate or douse the flames with water because the blaze burned itself out.