I have a bunch of last year's bamboo stakes that would be perfect for this project. Looks like I have a week-end project that isn't conditional to dry weather.
Wow. Great job. We have so many mud dabber wasps around here. I think they would take over the bee house. We find their mud houses in the holes in the wooden handles of our garden tools. They are great to have around as they get rid of many bad bugs.
If you mean mud daubers, I don't think they use man made stuff and 5/16 inch holes would be too small for them I think. Try making one.