How are they killing them (shrubs)? Building a den under them? We've had chipmonks for years but they never cause any harm besides arguably unsightly holes in the ground here and there. Moles on the other hand, digging tunnels, I've spent evenings just sitting out drinking beer on the lawn with a shovel in hand to catch those suckers and slice them in two. Usually I thrust the shovel a few times and if it comes out bloody, I leave them there buried in the ground.
Anyway, if you don't care about being humane, those peanut-butter scented large mouse sticky traps should work, or possibly a plain old, large, spring loaded mouse trap, given the right bait.