Mahopac Volunteer Fire Department is reminding residents that the New York State annual burn ban is  in effect through May 14th. Open burning is the single greatest cause of wildfires in New York State. Since the spring burn ban was implemented in 2009, the number of wildfires has decreased by more than 40-percent.  In the past few weeks the Carmel Fire Department has responded to numerous fires caused by open burning during the ban, the latest was Thursday and involved a shed fire caused by an open burn.  They were able to limit the damage and contain the fire before it became larger.