This attractive bee box is one of several that have been erected around the FWG, as part of a project by some bee researchers at the farm. They are looking for Osmia species, in particular they are hoping to see if a non-native Osmia is found (it has been found in upper New York State, so far). But they are also interested in other bees that would nest in such structures such as Megachilids. When I put up a bee box at the FWG a few years ago, Megachilids found it almost immediately.