We are practically on solid limestone, so burying wire is not an option for me either. I also put down an apron around all my coops and runs, but am using welded wire. If a raccoon can rip through chicken wire attached to a fence, it can rip through chicken wire on the ground, even if it is staked down. Chicken wire also deteriorates & rusts after a while so becomes weaker.
If you have small predators, like weasels & mink, that can slip through the holes of welded wire, attach hardware cloth underneath it, then stake the welded wire down on top.
If you have small predators, like weasels & mink, that can slip through the holes of welded wire, attach hardware cloth underneath it, then stake the welded wire down on top.