I use a similiar set-up, I have an old hay ring for cattle, I tied hog wire around it and used a one way trap door. I use t-posts to hold it down and they haven't dug out yet. It only works for a short time though, they seem to figure out it is a trap after a while. If you take the door off and continue to bait it for a few weeks they will start to come back in.


Chris "The lil piggy buster"
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"Tragedy is when I cut my finger. Comedy is when you walk into an open sewer and die."
- Mel Brooks