During the Spring and Summer time, it is hard to keep the beehive dry, due to the rain, and high bee population, which increases moisture inside the beehives. Bees start hanging out in clusters outside the hive, in order to make room and keep the inside dry for the rest of the bees and their queen. To avoid this problem, it is necessary to increase their space, by adding an extra empty box, or shims between boxes.
Fabiola Rivera 
I’m fascinated by your shims. I use similar I call an eke when treating for varroa in autumn. Do you leave them on all summer and do the bees not drawn the frame comb down into them or propolis them up? I put on extra supers for space, using my ekes would be easier!
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Hello, I only leave them on the Summer, because the temperatures in New Mexico are very high during July and August, although I am planning in leave them during the winter, to use the shims as feeders, and place sugar patties for the bees.
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