I asked the caller whether he had squirrels. He told me he had plenty of them. I surmised it was probably squirrels that were digging up his yard.
Squirrels take acorns or nuts and bury them in the ground. They will then come back later and dig them up. Sometimes they forget where they put them so they dig extra holes trying to find their nuts.
We often get calls in the extension office about holes in yards. There are several things that can cause holes. The size is a clue to the source.
A Norway rat's hole is the size of a tennis ball. A chipmunk's is the size of a golf ball. A pine vole (orchard mouse) makes a hole the size of a 50-cent piece. Emerging worms, beetles, and cicada killers might leave holes as big as a pencil.
Many people say they have snake holes. Snakes might occupy holes but they don't dig them.
I always ask whether any dirt is thrown out. With stump or root holes, dirt will not be thrown out. If a mammal digs a hole, they leave all the dirt thrown out in front of a slanting hole, except chipmunks might carry the dirt elsewhere and leave little sign.
Sometimes a forgotten stump with the roots will rot away, leaving one or several mysterious holes with no discarded dirt at the entrance. People swear something is digging, but it's not. Dogs might enlarge these stump holes. Sometimes a creature might occupy these stump/root holes. They just didn't make them.
Deep burrows usually indicate the hole is someone's residence. One trick is to till and smooth the soil at the entrance. Another is to sprinkle flour around the hole. If an animal is there, it will leave tracks.
Shallow holes, especially if there are many of them, often indicate that an animal was digging for food.
If you live in more remote areas, skunks, raccoons and armadillos love to dig for grubs or earthworms. These animals pull the soil out to one side. Armadillos dig an inverted, cone-shape hole, 3-4 inches deep and 1-2 inches in diameter. They can tear up an entire yard overnight.
Most holes made around here in residential areas are made by robins, blue jays and squirrels. Blue jays put acorns on the ground and pound them in, making a conical hole about 2 inches deep.
Robins dig looking for grubs or earthworms. They can detect subterranean prey.
Animals such as rats and armadillos need to be controlled, but in almost all the other cases, you probably don't need to do anything.
Sid Mullis is the director of the University of Georgia extension service office in Richmond County. Call (706) 821-2349, or send e-mail to firstname.lastname@example.org.