Not sure, Jim. I was going to try and grow it, but don't have a wet marsh on my property. I found that it grows wild near by, but never was able to find it. I have purchased it dried. It appeared to be both stem and leaves chopped up. I did a little search and it appears rather safe to use with caution. I read the stems, leaves, and seed were edible. I would not eat it until verifying it is edible. For medicinal uses I have made a poultice with it and found success in treating an eye inflammation.