Suz;
You have real problem. I would go to a local nursery nd talk to them about it. I suspect they will suggest some kind of really tough grass such as fescue 31. You have a lot of hard work ahead of you either with a tractor or a roto tiller. Since it is a hill, I would not dig very deep or the whole thing will wash down. I would think that something like Fescue 31 ( I think thats right) would do the job.

I would rake it down sow the seed and straw it and then keep it wet until the grass comes up.

I don't envy you.

John

What about taking all those rocks, building a raised bed and filling it with good dirt? You could either plant flowers or just have grassy terraces?

Janet

Hey Suz...If you don't want to do it with grass, Lily of the Valley would sure take care of the problem, very fragrant and spreds quickly. I have it around my pond for erosion. I could even send you some starts. Daylilies, I even have a succulent, can't remember the name of it, it is in the sedum family blooms with littly yellow stars in spring. It grows everywhere, can be invasive but easy to pull out. I could send starts of that also. Just let me know if you would like some. Martha in Louisville, KY