Went and looked at a job today at an assisted living account that I have had for 3 years now. something is digging holes the size of a quarter at a 45 degree angle and undermining the walkway. I have caught many chipmunks here over the years, but these holes just seem too be too small. Maybe im wrong. Any Ideas? The first pic is a fresh hole the second one after the holes cave in.

First pic resembles what I see from cicada killer wasps but they are usually accompanied by the wasps themselves and I've never seen their tunnels collapse.
I would lean towards some sort of small rodent like a vole. We have very few of them here so that's a surmise on my part.

Dang it David, you beat me to the cicada killers! We see that lots out here, along with tarantula hawks! Just found two last week dead after the last storm.

Would agree, rodent is likely...

Looks like Voles to me.

x2

I set it up tonight. I think you guys are right with the voles. hopefully I will see in the am.

The second picture are they chewing threw cement or block I've been deal with a lot of Norway rats eating threw block , Mortor , cement , cast iron pipe ect . Got called on one today rats went right threw block again . I'm done playing with these rats went to mostly number 11s DLS

well, ready for a laugh? The small holes were toads, i've seen toads in holes before but these were deeper than my finger. I had ten toads this morning. The caved in sections of the walkway was done by chipmunks. The small holes apparently aren't related at all! The chipmunks will be taken care of tomorrow. I was really hoping for voles.

Ten toads well atleast it was easy to count them .

A few more and you'll have enough for a cocktail.

So another twist to the story. I dont know why I was catching so many toads but they weren't the main hole diggers. Turns out those of you that said cicada killers were correct. I saw one digging a hole this morning while I was setting up for chipmunks.

Thats awesome Steve!

My father in law thought he had rodents last year and we told him about the CK and literally the next day he sees one hauling out of the hole while digging!

The insect kingdom is almost a weekly lesson out here, I've seen stuff I never knew or thought about in other states.

Justin

A squirt of delta dust in each of those holes will do the deal on cicada killers.

CK's are somethin' else. Scare the crap outta people 'cuz they're so big, but ya almost can't get 'em to attack.

don't have them here. Ive never seen one.

Think of a mockingbird that digs holes.