Photo? FAIK only 1" chicken wire or hardware cloth will keep out chipmunks.

Dave

Probably one if the hardest critters to keep out; they can climb through or over most fencing, and can dig under anything small enough to keep them out. IMO, easier to just trap them.

Yes, I think the only fence that works against chipmunks is one with traps spaced around it.

I like Susan’s 3rd option best, but will add that an outside cat helps. Just keep him a little hungry. :-) I commonly find a beheaded chipmunk or squirrel on our front doorstep in the early morning. He doesn’t eat them, just kills them and leaves them, providing me some compost material. Garden protector!

Google chipper dipper. When I get a chipmunk problem, I set the trap over and over until I get no chipmunks. I will typically get 3-4 in the first few hours. They still come back every year, so don't worry that you are killing off the population. I don't want chipmunks nibling on my vegetables. They are a rodent, and they are a pest to both vegetables, and digging holes under porch/house foundations. Think cute rat. I use old grilling tongs to throw them into the woods. My local foxes never let them go to waste.

"Common chipmunk diseases include leptospirorsis, salmonella, Hantavius, Rocky Mountain spotted fever, encephalitis, rabies, and the plague. Some of these are spread directly through contact with the pests, their feces, or their urine, while others are transmitted indirectly via ticks and fleas."

so double up the fencing won't work at all?

3rd the traps and outdoor cats, even feeding feral cats if you have some.

Put the traps under a bucket or in a jar or can so innocent passers-by don't get a foot caught. It also insures the bait is approached from the business end.

There is also this that drove them out of my garden and farther into the woods line. Solar Mole and Gopher Chaser

This is a time when you need a 3 pronged approach.

Xx...double fencing works for deer because they have poor depth perception. Other animals will climb over, under, and through the fencing.

I would use 1/2" hardware cloth all over the sides and along the outside perimeter (buried flat), but still.......those guys can tunnel under very long distances.

P.S.....that's a very nice fenced area. What are you growing in it? I've always wanted to make a fruit cage like that, but with a top on it, to keep birds out.