Hi,

They could be woodlice except I don't think I'd ever describe their movements as "running" :) Interesting, in the wiki article it mentions that they arrived in the Americas from Europe...hmm....how can they ever really know that they weren't already here?

Here is a link that might be useful: woodlice/pill beetles

http://www.sactorose.org/rosebug/

I've got those eating up some old rotting logs, they are great recyclers in my opinion. If they don't do it the centipedes and/or ants will do it. They make great woodsy soil for me. I just use a garden fork, and make lots of holes in the ground, then put the woodsy humus type stuff these critters make on top of the "Holey" soil and water in, maybe making some extra holes once the wood-dusty soil is in place. It is the closest I can make woodsy soil or humusy soil in my yard. I know that this wood decay stuff can be roto-tilled in. but I have read on the 'Soil and mulch" forum that it's best not to mess with the "soil structure" if you can avoid it. I currently have a yard with several trees, with their own "Mulch circles" around each tree. No mulch-volcanos, of course. Most of these trees are about 15-20 feet tall. Eventually they will make a very shaded yard. Some of them, well, 3 of them are large enough that I have made "shade gardens" under them. I have 2 that have a handful of shade plants thriving under them. But, anyhow, after a longwinded post, I will say, those little Crustacean's are great at recycling good stuff for your woodland, making great humusy soil.