I've read a lot about top entrances and know what Micheal Bush says about them. I recently built four new TBHs and drilled holes in the lower sides to match my first hive. But, I've left one with no entrance. My hives have sloped roofs which leaves a space between the roof and the bars.
Another man in Tennessee recently told me of a friend who had recently lost a large percentage of his 40 TBHs to SMBs, since the beetles could get on top of the bars and the bees couldn't get up there to run them out. My bees can get up there from under the end of the roof, but I've rarely seen any up there. For that matter, while I did see SMBs in my hive, I never saw any above the bars.
I know that Mr. Bush uses flat covers with small spacers to hold them up and let the bees in to the top entrance slot. Does the open space between the top of the bars and the inside of the roof make any difference when using a top entrance? Or is the small space/ flat cover required for a top entrance?
Re: Top Entrance
SMB = small hive beetle. I can't spell. I meant SHB.