My two backyard hives have SHB. I use traps but the problem persists, although minor. So I am thinking that perhaps I can augment the traps by using Diatomaceous Earth around the hive, but use slightly different approach than simply sprinkling it around. I am thinking of pulling up all the grass in two 4 foot circles and adding a 1/2 inch layer of the Diatomaceous Earth to each, and then covering each with 3 inches or so of mulch. Then put a hive in the center of each circle.

Are the circles wide enough?
Would this be effective or are there risks here I am not considering?

Thank you.