Big thing is there are SO freaking many! A shovel turned shallow anywhere in the woods or lawn will have a dozen of the dang things squirming every which way. And they run quickly.
If birds got into them, a four foot square would be a pound of worms I'm guessing.
I take them out of the compost (hand picked! ;-) in gallon buckets. Drowned in soapy water.
I'm looking for a magic bullet, but as they are all around for miles, I have no assumption that my local activities will have any useful results. They all die in winter, only to hatch out from "cocoons" in spring to start all over. Maybe if we get a dry year, they will not prosper so.
The castings do make nice dark soil, but not sure how it analyzes. It makes pulling weeds a breeze! Loose and crumbly. Plays all heck with mulching though.