Fire crews in Vallejo, northern California are battling yet another brush fire which is threatening residential areas.<br /><br />After weeks of drought and high temperatures emergency crews are being stretched to cope with this year’s wildfire season.<br /><br />So far this year, the California Department of Forestry and Fire Protection has responded to 4,294 wildfires which is more than last year’s average of 3,311, according to a weekly drought brief.