I remember reading somewhere that you can introduce a lot of bad (bugs, microbes, etc) into your bin using leaves from your yard.

KimC has an excellent point, a lot of the vermicomposting info targets indoor bins - although I'd say most of those 'bad' bugs, microbes, etc would only really be nuisances (in a house context).

I'd also add: for many the issue with leaves would be having a constant, year-round supply - whereas the usual cycle is having a _lot_ in fall, and then limited amounts after. Cardboard and paper works for most people year-round, in whatever amounts are needed; leaves might tend to get added in enormous quantities at once.

Finally, 'leaves' can be very different - freshly fallen (still relatively green), fully dried out or quite wet, mulched or not, partially decomposed or not, etc. So giving advice about how to use leaves in a bin a bit more uncertain than with cardboard.

That said, I fully agree that leaves are great and worms do well in them. But my 'bins' are really just large outdoor compost bins where the worms are in charge, and they thrive on neglect (good thing).

Well stated, thanks for your responses, very eloquent! Maybe others will chime in with more examples and ideas.

All are on target. Shredded cardboard and newspaper are recommended so often because of their availability and landfill relief. People who don't have access to leaves (those in large cities) can easily get CB & NP. Leaves (specifically leaf mold) are very good for worms. Nature's food menu.

IMO it's best to have a good variety for your worms. I use shredded CB & NP along with leaf mold, well aged grass clippings, horse manure and spent coffee grounds as my carbons and various veggie and mellon scraps for my nitrogen. Do worms have to have the variety? No. But variety makes for great quality vermicompost. And my worms go to town on their decomposing buffet.