Ok.. So I've seen pollen traps for TBHs before, it's really a no brainer... But what if you want to set up a propolis trap and collect some? I'm trying to figure out a logical way to do so without being stupid about it.
I've seen some TBH bars which seem to have a 1/4" spacer that goes to the side of them? Not real sure why, but got to wondering if I couldn't just do something similar and pull spacers as needed to place a propolis trap.
What are your thoughts?