I've got what I believe are cluster flies in every window well and buzzing around every window in my house. Would it be best to spray or fog?
Unfortunately, you are past the time to treat your home for cluster flies. Cluster flies enter your home in the late fall, early winter, usually around late September/early October. The flies enter through cracks around windows and doors and under siding. As the weather warms up or as your heat kicks on, the flys will emerge. Most will go outside but some will be confused and end up in the house. Next year, you should treat the outside of your home earlier in the year to prevent entry. For now, you can spray the inside of the home to help kill flys that are still in the wall. If you spray baseboards, window sills, etc you will kill the flies as they come out. As far as the flies that are in the house already, I would suggest our CB PCO Fogger with Pyrethrin. It should kill any that are flying around in the room you set the bomb off in. Be sure to read all directions and vacate the property for a few hours after setting it off. Cluster Fly Control Article
Answer last updated on: 11/10/2009