Am using black plastic for mulch, and when I look underneath there are a dozen or so centipedes. Also a lot of tiny gnat-like creatures. Read somewhere that centipedes feed on the roots of tomato plants, but some feed on small flies. Do I have 2 pests, 1 pest and 1 predator, or nothing to worry about at present? The plants are healthy, other than a few old flea beetle holes(I won that battle). While trying to not answer my own question about not worrying as the plants seem fine, I'm just wondering if I need a pre-emptive strike against the 'pedes in order to prevent problems later. Anybody here had a problem with them in the past/present?