You can wash wool. I have made things with it before. I do suggest that if you want to machine wash the final product, that you pre-wash before you make your project. You will find that the wool will felt together causing some thickening, shrinkage, and distortion to the original piece of fabric. It does make for some snuggly warm quilts though. I have even used whole, old wool blankets for batting once they were machine washed.