Thatching as Sustainable Roofing? -- Low Tech Podcast, No. 58 

It takes contacting the DNR, explaining why you want to do it, and the steps you'll take to reduce spread. For example, I harvest and cut the heads off in the original reed bed, so I'm just transporting the stalks. Also, they are stored in non-wetland locations to avoid sprouting. The difficult thing is that most stands you find now have multiple years of stalks, which is not good for thatching. You have to mow down or burn off the current mat of stalks about this time of year so next year's growth is all the same crop. After the first freeze next year, you could harvest. After that, it can be harvested each year. It is a multi-year process!

@@LowTechInstitute The fact that reviving the use of utilitarian thatching would encourage the annual mowing and harvesting of phragmites that with proper handling might reduce the its ability to spread to native wetlands. A win win.