Answer: What you describe sounds very intriguing, but nothing that I can identify without seeing and examining under a microscope. Since you're finding them in wet or damp places, I suspect they are Springtails. You might do a websearch to see if you can find a photo to compare with what you're finding in your garden and home.
My suggestion is that you collect some of the material in question, place it in a sealable plastic bag, and take it to your local Cooperative Extension office. Helpful folks there will be able to figure out what you're dealing with and make suggestions as to what to do. Contact University of California Cooperative Extension, 5555 Overland Ave., San Diego, CA 92123. (858) 694-2845
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