I had my best luck with the core of lettuce. I hang it inside the trap past the treadle and then sprinkle some lettuce on the ground and into the trap.
I've probably caught 5 'chucks so far and 3 rabbits. More have died of lead poisoning. All my neighbors either shoot when I don't or cheer me on when I shoot.
I had one rabbit I wounded and started chasing across the yard. My neighbor was on a second story deck hollering "Git 'em Russ, git 'em".
We all laughed our ass off. He crawled under an out building and that's the last I saw of him.
As an aside, the building he crawled under is owned by a friend who has a bunch of LARGE pythons and Boas as well as quite a few venomous snakes. I believe they have had their venom removed. Rattlesnakes, a Gaboon viper and other assorted snakes I am unsure about.
Dan the Snakeman. You will be hearing his name soon as a household name. He's going Youtube.