something I'd like to know also. I live on the banks of a river and have acres of phragmites. If I thought I could use them I would try it. I am sure I'd have to cut them up quite a bit though because the leaves on them are sharp enough to cut my skin!
Rushes are not poisonous and are an aquatic type of plant (they like their feet wet). Chop the rushes up (mow and bag or run through a yard chipper shredder) and mix with leaf litter or woodshavings. Use this mix as a bedding in the coop and you will have a deep litter system. Deep litter systems are usually 8 to 12 inches deep...some deeper; others not so deep.
Thanks. I may just have to harvest some. My neighbour has a "bushwhacker" for his tractor and would be happy to cut down a stand for me. I'd have to collect them then move them to the house by hand though. Then we could use our lawn tractor to chop them. Lots of time to figure the logistic out between now and then.