A simple trap is a Dungeoneering item used to catch ferrets in one of the puzzle rooms.
To make this, left-click "Make-trap" on Dry logs which are cut from the wall inside the puzzle room itself. You will need the required fletching level to do so, which varies based on your team.
You can only make this trap out of Dry logs. All other log traps are used to catch Bovimastyx.
Strangely, this trap has a destroy option rather than drop. It can, however, still be traded to teammates.