Clay for Mason Bees
What kind of clay should we provide for Mason Bees? We have recently obtained mason bee houses. On the literature it suggest providing clay for the bees. One site is willing to sell what it calls "Mason Bee Mud;" Do we get food-grade bentonite from Amazon? Kaolin? Or will pottery clay from the local art supply store do? We do have a local stream bed and I am not above digging some up for them but I do not know if this is a good idea, especially since it is a drainage stream in my town and I can't swear that there is no chemicals from my neighbor's yards flowing into it. Any suggestions would be appreciated.
Prince George's County Maryland mason bees
In general these native bees know best. Their activity is early in the season and they should be able to provide their own mud. They like damp mud for walling up their nest cells. If your soil is sandy, you may need to make a little mud pit. In dry weather, you may need to water your mud. We do not have specific research on purchasing 'bee mud'.
See the attached link http://extension.psu.edu/plants/tree-fruit/insects-mites/pollinators/solitary-bees-mason-bees