You can propagate those to an incredible extent. Here's how I do it. Dig them up. Spray all the dirt off or as much as possible. then cut them into 3-4 inch diameter groups. Get some good shrub potting nursery mix, some 1 gallon pots and plant them up. You can use the ones you need and sell the rest. I do this with overgrown daylilies as well.
" I see it all the time, new guys come in guns a blazing then they go out liquidating" DKOESTER