Holes in the backyard

For a few weeks now, I've been noticing small holes show up in our front yard. They are the kind that could do some serious damage to the foot/ankle area if you stepped on one and didn't know they were there. I originally thought there were put there by our fearless, insect stalking, toad eating dog. Turns out, I was wrong. They are from Armadillos. I wonder if there is a way to Armadillo proof you yard?

Mood: Resigned
Background Noise: Lunchtime natter