Does anybody know of a source for these plants? I have read that they are a medicinal plant that is somewhat valuable. I'm wanting a plant or two of my daughters butterfly garden. They are a host plant for Pipevine Swallowtails. I figured that this was a good place to ask for help with all the people that are into the root digging. In Michigan they are considered "threatened", so I don't think finding a wild plant and transfering it a good idea.

Here's a nursery that sells the plants: https://www.horizonherbs.com/product.asp?specific=1078

How strict is the law in Michigan? Do you think that you can even have some shipped to you? Check and make sure you or the shipper can't get into trouble. You can't be careful enough these days.

I'll check. I know of a few butterfly gardeners that have it cultivated for their own use and one that was going to sell it but she couldn't get the seeds that she collected to germinate.

I have some. Be more than happy to send a couple.PM me if interested.