What creature dug this burrow?

[fuzzi]

Chipmunk was definitely one of my guesses.

Do you think a chipmunk would be active after dark? My dog doesn't normally react unless he knows that something is right there. I thought chipmunks were mostly active during the day, but I could definitely be wrong about that.

Putting flour around the burrows should help solve this mystery. I hope!

Did you figure it out, yet?

I have similar holes in my yard, but think they're from squirrels...except they're so symmetrical!

I also have moles, and small critters I think are shrews.