I've been using some dried grass clippings that I gathered and bagged in the summer heat, just to try something a little different.
Line the bed with grass, pack grass all around the trap, and cover with grass. I toss a handful down the dirthole to make it look as if a nest was dug out and spread some around outside the pattern as well. It has a pleasant dried grass odor that I'm sure holds some attraction on its own.
And yes, you can use my nail method to bed rock solid even in a handful of dried grass, LOL