>>told me that some important factors to consider are not restricting 
air flow (use screened bottom boards) and allow ample entrance 
openings under the trap (large side rails on bottom board) so the 
bees can come and go without jamming up at the entrance.

I am not sure if I followed.  Wouldn't the bees by-pass the pollen 
trap and use the openings under the trap?

Waldemar

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