I've heard orchard grass hay is better because it is softer. I've also heard that alfalfa hay has too much protein. This is just what I have read here, my tortoise does not eat hay and it does not make a good substrate.
Thanks for your replies. Being a bale of hay lasts me a long time, I would like to find out, which is best for hatchlings to adults. The last bale was green alfalfa, and they seemed to like it.