Leaf cutter bee infestation

I have leaf cutter bees that nested in the styrofoam around my house. We covered up the nests and built a deck but the bees are persistent and want back in their nests. I was wondering what I can do to get rid of them so they start making nests in my new deck! Bracken.

Leaf cutter bee infestation: Leaf cutter bees are not known to cause serious damage to sound wood; if ready-made cavities are not available, they prefer to make tunnels in soft materials such as the pith of plant stems or rotten, punky wood. And in your case, Styrofoam. Styrofoam blocks sometimes are used in making commercial nests for leaf-cutter bees. Just be certain that it is indeed leaf-cutter and not carpenter bees that you have. If at all uncertain, submit photographs for identification. I have seen formulations containing bifenthrin (a synthetic pyrethroid) recommended as a repellent for leaf-cutting bees, but bifenthrin currently is not registered in Canada.