VIDEO: In firefighting circles, it’s brush fire season, the time of year when the forest floor can carry flames well beyond their intended boundaries. In some cases, these fires are the result of people burning brush or having a campfire; others are sparked by cigarettes or a spark from an engine. The state Department of Conservation and Recreation’s Fire District 7, which encompasses 32 cities and towns, including Worcester, keeps tabs on the wooded landscape from watch towers spread throughout the region. Three seasonal firefighters were deployed in recent weeks to complement two year-round state firefighters who staff the towers.