My daughter lives in Kansas City and is plagued with squirrels and chipmunks. She's finally observed chipmunks eatting her newly potted plants. They've tried cages and a wide variety of things with little success. What works best to stop these little guys?

She might try Rat Magic. Not as deadly as it sounds. It's a blend of different oils that some of the rodents aren't fond of. I'm using it around some transplants myself and it does seem to keep my chipmunks from digging up new plants.
.bonide.com/products/garden-naturals/view/863/rat-magic-rodent-repellent

Thank you Cindy! I'll send her this information to check out. She has a very active shady backyard with birds, squirrels, and chipmunks but her plants always suffer because of them.

A CAT, a big, twenty pounds or more, lazy CAT .
All he or she has to do is just sit out there bathe in the sunshine.
The squirrels will sit in the tree going, chat, chat, chat, chat, the chipmunks will avoid that area and even the birds will watch from afar.
Now he/she has to be a cat that will hunt down, one critter each spring, just so it knows it can still do it, and show the critters he is not as much of a putz as he seems.

Rp is right! I have a feral cat here that I do feed just enough to keep him in form to hunt chipmunks. He doesn't bother birds but small rodents on the ground are fair game. He maybe catches a couple a season but maybe scares away enough to help.

Marta, I use hot pepper, as I was taught by my grandfather, and it has worked for me in the past, and it's working for me now in a more rural setting (but squirrels know their way around an urban landscape too!) I sprinkle it around my plants, dampen it so it doesn't blow away, and there you are! Doesn't hurt the birds. Right now, after establishing parameters, I have a chipmunk and five squirrels sharing my backyard with two squirrel-proof bird feeders and two birdbaths and plants in the ground and on two deck levels, and I haven't had a problem with them. Did have one with a raccoon who thought the suet on the shepherd's crook was for him, but I took a rag, scooped out a big glob of Vaseline, mixed cayenne in it, and smeared it on the shepherd's crook and peace now reigns again

Thank you all! There are feral cats in her area (urban) but they don't stay at her corner lot. She does have a resident Cooper's Hawk or Sharp Shinned Hawk. Her miniature Schnauzer chases all of the critters to no avail. He is the deterrent to having a cat. I'll tell her to try cayenne pepper also mixed in Vaseline as needed.

@Garden10
     What kind of hot pepper do you use? The culinary hot pepper flakes or ground up chilis?
     Chipmunks are really a problem in my yard as well as the garden. I tried stopping up all the chipmunk holes but they dig new ones. I bought a commercial repellent but on reading the fine print in the manual it said not to use it near vegetables. So I poured some in the yard holes. I still see the pesky critters. In fact one hopped up the stairs to our porch yesterday.