Your itty bitty snails are probably itty bitty babies. They can do a lot of damage to plants and evidently mom thought you had just the right environment for them to live in and they are thriving, just like she wanted them to.

I would suggest you buy some "Escar-Go" or "Sluggo" which are non-toxic organic snail baits (iron phosphate based broadcast spread at 1# per 1,000 sq.ft. with two or three applications needed).

Even a small amount of the normal toxic snail baits would make your dog very sick should he/she be curious enough to taste it, but the organic baits would not and are not appealing to dogs anyway.

If you are a new gardener, my humble opinion is that although there are lots of easily obtainable chemicals for deterring critters, there are many organic and non-toxic products that are so much better for the environment and ultimately you. There are also a lot of home remedies that are just as effective at very little cost, an example of which is to use straight vinegar sprayed on weeds in the cracks between bricks, and a mixture of 1 T. baking soda in a gallon of water to spray on black spot and mildew, or sprinkling baking powder on curcubits (cabbage, broccoli, cauliflower, etc.) to deter cuke beetles, sprinkling cinnamon at your doorways to deter ants from entering. The list goes on... The info is out there, it just isn't publicized because there is no profit in organic controls you can make up yourselves at home.

Nancy