Sounds like a really cool title for a children's book. I'd say you have VOLES, my dear. When you water or it rains, they will tunnel through the soft earth, munching on your plant's roots. Moles and gophers and shrews (and snakes of all kinds), use their nifty tunnels to get around your yard subteranean - like a handy-dandy animal subways. Crickets use them, earthworms, and slugs, too, and lots of other critters. Some good for your garden and some that don't seem to be so good. I've lost tuberose salvias and my favorite tea roses; tulips and petunias, even cactus roots. If its edible, they will eat it! I've tried various things, like tarpaper collars around my roses and concrete or rock barriers, even strips of sheet metal buried around them. The tarpaper worked pretty good until it disentigrated, but eventually, mice burrowed through it and then it rotted to dirt. Flooding does no good, as those tunnels are hundreds of feet long. Those holes will never fill completely up. I've tried it. :) If you have a serious vole (or other rodent) problem, like I do, your yard may be completely undermined with tunnels that links with your neighbor's, and their neighbor's, and so on...hence you may find a flower in your yard (or weed) that you didn't plant or never saw before. Birds can bring carry them in or deposit them in your garden, via their poop, that's true, but so can rodents. Rodents carry seeds back and forth through those tunnels to and from your place. Keeping things in balance with Nature is what works best for me. If we can stop fighting all the elements of nature and work with it, we will get better results and enjoy gardening even more. I sink bottomless buckets in the ground for barriers for my big lilies, around berry bushes and roses, and even some of my garden plants, like my tomatoes, and that works really great. For shallow rooted plants that send out roots horizontally, these don't work so well. Planting daffodils, irises, liriope (Monkey grass), garlic, zinnias and stinky marigolds around the borders of my flower beds and/or around blueberry bushes, roses and strawberry beds, even apple trees, is about the only things I've done that works relatively well for an indefinite period of time, without killing the beneficial micro-organisms in the soil and harming animals like shrews and earthworms and preditory insects and snakes. Garlic really does a great job warding off rodents from my roses and they both mutually benefit from one another. Daffodils, irises, and liriope are poisonous so rodents just don't dig 'em. I think we gardeners and farmers will always have our challenges, but isn't that what makes our successes so awesome! ~ SweetAnnie4u

Congrtulations on your cat! A good mouser is worth their weight in gold. Some are not good, though: I think they need to learn the skill from their mothers. You got lucky to find one that knew what to do. My present cat will chase them but plays with them so long that half get away. My previous cat would clobber them once, administer the coup de gras and eat them on the spot. No letting them get away.

"Should I try to get some "Great stuff" to spray into the wall adjoining the garage? (This sems to be the entry point)?" If you do try Great Stuff, I'd recommend doing so only after you first eliminate them all first (where there's smoke...) otherwise you might close it/them in and have a worse problem. Pesky little things mice are. Especially this time of year in the northern hemisphere.

I have your answer. I have seen it all and every mouse trap gimic made. This is what works fool proof. You need a old fashioned wooden based mouse trap with the spring loaded bar. You need the trap also that has the small brass or steel catch that curls upward in the front of the catch plate. Now take a piece of Nacho Cheese Dorito chip and break off a piece the size of a nickle and wedge it under the curl of the catch plate keeping as much intact as possable and not hampering the trip of the trap so the mouse needs to tug on the chip to get it loose. The point then is to feed them where you want them to go. They cannot resist the smell of the chip. I recently fired up my trap again and cought 5 mice in 2 days. I have 1 trap the has 16 kills marked on it and another that has 7. Be sure to check about every 3 hours and rebait as needed.