Steve E from California, contacted me about setting out mason bees in an almond orchard. He asked me for feedback on his idea of constructing a housing unit for mason bees out of a plastic barrel.
” I brought the two plastic tubs into my garage and took this photo of the 2 containers side by side. You can see that the all-blue barrel is uncut, while the white one has a cut-out door of about 12″ x 16″ bordered by black tape. Within the barrel are stacked cinder blocks. You can make out a roll of cardboard tubes within one cinder block. On top of the cinder blocks is a wood bee block.
So, if these barrels are only 33 inches tall (a bit less than one meter), are they too short to be effective ? The diameters are 23″. I could put a stack of cinder blocks out with a wood pallet on top, and elevate the barrel on the pallet to gain some height. But that would make it more vulnerable to the wind, as well as more work and materials for multiple sites.
I can obtain these barrels quite easily, and they are simple to cut out. The temperature within vs. without is at least 5 degrees warmer on a sunny day. On an overcast day, at least the blocks are protected from the wind.
I can put vent holes in the top or upper edges. But these are targeting February and March activity in an almond orchard and plum orchard, and it is generally lower to mid 50′s F in those months.
Please comment on the potential efficacy of this simple housing unit.”
COMMENTS: The bees may behave/forage/fly differently in the blue and white unit. Setting them side by side would make for an interesting test. Cut a hole in the center of the top (4-6″ diam) so excessive heat can escape. Also disoriented bees can fly out through the top and re-orient to their nesting tunnel after flying through the door. Set cinder block against the sides, so to avoid any rain coming through the skylight hole and falling onto the nesting tubes. Secure from wind. Set out in an open and sunny location. Set up 3 thermometers: 2 inside at different heights and one on the outside north wall for comparison. I look forward to hearing more about this housing unit.