Thursday marked an early start to fire season. A 4-acre vegetation fire, allegedly started by a Nevada County homeless man, broke out near the intersection of North Bloomfield and Rock Creek roads, outside of Nevada City. The fire was reported at 7 a.m. Thursday but had likely been burning all night, as many residents in the area reported the smell of smoke throughout the evening. “There was about a 4- to 12- inch flame length, and there was some singe up on some of the trees,” said Cal Fire Battalion Chief Sean Griffis. “It was a small backing fire largely …