Answer: If you are insistent on growing grass, perhaps you should consider using one of the tall turf type fescues. These are tough grasses that need little coddling and will usually thrive in poor soil. It will take some work to get it to take hold on a hillside, but it can be done. I would contact your cooperative extention office (ph no. 417-345-7551) for suggestions on the varieties that are best for your area.
Otherwise, would you consider using a groundcover other than grass? There are many great plants out there that will hold the soil in place and give you an attractive planting that doesn't need mowing. Some suggestions: bugleweed (Ajuga sp.), wintercreeper (Euonymus fortunei 'Colorata'), landscape roses, fragrant sumac (Rhus aromatica), Thyme (thymus serpyllum), Boston ivy (Parthenocissus tricuspidata).
Q&A Library Searching Tips