Screened Bottom Boards are used to increase ventilation and reduce mite population in a hive. Increased ventilation helps keep hives healthy and strong year around. They also help reduce mite and hive beetle population by allowing any mites or beetles that fall from the hive to pass through the screen to the ground below where they can no longer trouble your bees. The Screened Bottom Board can also be used with a sticky board. The Screened Bottom Board is made of pine with a galvanized hardware cloth screen.