Larry about said it all. If I have a big old clump that I plan to get rid of altogether, I use the Jetstream setting on my watering wand and get as much soil as possible washed off, then first try to divide by hand. Sometimes the clump is too large to get up all in one piece, so may use a shovel to first cut it into 2-3 pieces, then wash and start dividing. If they won't separate by hand, I go to a knife. If the clump is fairly small and I just want to share a fan or two, I push the shovel in near the fan I want to remove and sort of pop it off. That way the part I keep doesn't get disturbed as much. It's easy to damage a fan or two no matter how you divide, so I don't suggest it when you only have 2-4 fans.
