A friend and I went spade ready to add to and turn a new this year compost bin made of 2x4's. A foot down we ran into an ugly mess of grub worms, slugs, and centipedes along with some very beatiful nightcrawlers and red worms. The compost was very wet at that level which seemed odd as the top was barely moist. We (UGH) handpicked all of the grubs and slugs we could find and mixed in shredded paper and a bag of purchased topsoil hoping to soak up some of the moisture. The kids had a great time with salting the slugs and grubs. According to my googling search, the grub worms are from Japanese beetles - have never seen one out here, thought they were an Eastern rose bush problem. Where did they come from and what can I do to prevent a new batch from showing up at the next turnings? I have cukes planted on one side of the bin, the other three sides are part of a raised bed - should I dig everything up now, haul it to the dumpster and start over?