Fleas may have gotten into my yarn collection. How can I de-flea my yarn without resorting to harsh chemicals?

Put all of your yarn in a plastic tub and sprinkle liberally with Borax Laundry Booster, it repels fleas.The fleas throughout the rest of he house will have to be dealt with too, or your problem wont go away. Use the Borax on the floors and run the sweeper a couple times a day. It takes a while, but you'll get rid of them eventually.