I am on a southern slope in Johnson City TN and no solution so far. Liriope (lilyturf) is good where I don't have a lot of traffic, cut it in very early spring and that's all, and it it virtually indestructible. But not a native and looks boring. A portion of my slope is held together by this crawling red cedar variety, it is nice but took a while to get established.

You are seriously limiting your choices if you insist on natives. If you can drop that stipulation, there are dozens of good selections. As long as the ones you choose are not invasive in your area, I see no reason not to expand your palette. (Just my two cents worth.)
BTW, I hail from Kingsport, Tn., so am somewhat familiar with your climate.

Good ones I have grown here in Mississippi:
purple muhly grass (muhlenbergia): This is my favorite for beauty, easy care, long season of interest, and ease of maintenance). When it blooms in the fall it will stop traffic, literally.

Miscanthus varieties: Gracillimus, Morning Light, Rigoletto, and Adagio are all beautiful and low maintenance. They get pretty big. Their one fault is their need for division every few years. Since their root balls are massive, division is an extremely strenuous task. Still, they are unsurpassed for beauty, IMO. They can be expensive, but if you buy just one pot and divide it into equal parts, even small parts, they grow so quickly that you'll have all you want in very short order.

Mexican Feather Grass: a truly lovely graceful small grass. It doesn't love my humidity or my irrigation system, but I would imagine it would do fine where you are if it is winter hardy.

Calamagrostis is also a lovely grass. I have Overdam, which is a variegated one. In my climate it needs some shade, but I bet it would love your area.

Panicum vigatum (switchgrass) is about 4 feet - the cultivar 'Shenandoah' is supposed to get 3-4 feet.

I really like Schizachyrium scoparium (little bluestem), the cultivar 'Prairie Blues' is listed as 3-4 feet.

Miscanthus has been exhibiting invasive tendencies in SOME areas - I would research that carefully for your area. Liriope is not native and is not a grass either.

You might also consider some of the native Carex species.

There are a lot of options, actually. Not very limiting at all. But to help, I think we need a little more information about your site. I know its a south slope, but does it get full sun? High shade? How is the soil? Is it very dry, moist, or does it have water from seeps? Are there other plants there now that can help give an idea of what the habitat is like?

One of my favorite grasses for moist slopes is river oats (Chasmanthiunm latifolium, aka Uniola latifolia) If your site will support that species, it might fit the bill.

Great answers you guys, thank you so much!

It does get full sun. No water, very dry in the summer. Soil is very rocky. I would say fair fertility while my dad thinks its very poor.

My father was able to eradicate the kudzu that was growing there but there are always a few sprouts that pop up. He had crown vetch mostly established but it died out recently. Any guesses why? We were thinking some of the recent droughts.

Currently there are some blackberry patches growing and surprisingly good areas of cool season grass, looks like fescue and rye.

There is the ability to irrigate to get stuff started but would like to find some things that could spread on their own with no irrigation or maintenance. Like the creeping red cedar and grass suggestions. I wouldnt mind doing a variety of things but I think dad is looking for a perfect maintenance free species..

Here's a few that I think might fit the bill nicely and are native to TN:
splitbeard bluestem (Andropogon ternarius)
purple lovegrass (Eragrostis spectabilis)
Indian grass (Sorghastrum nutans) - this one has nice deep roots
little bluestem (Schizachyrium scoparium)
switchgrass (Panicum virgatum) - popular in recent years, so easily available commercially
bottlebrush grass (Elymus hystrix)
broomsedge (Andropogon virginicus) - some people really like it, others prefer grasses with fluffier seed heads.

I think that all should do relatively well given your conditions. Might want to try a few of them and see which do best. You can plant little swaths of each species for a nice effect, too.

Thanks nativeplanter, some new ones to me. Can you recommend a good source, nursery or mail order?

The best thing is to find material that is local to your area. It will be the most likely to be genetically adapted to your conditions at the site (as opposed to, say, a nursery in MN when you are planting in TN).

A quick search of the Lady Bird Johnson wildflower center yielded these results in TN:

http://www.wildflower.org/suppliers/geo_search.php?passstr=-86.5804473,35.5174913,0#map

You can also do a search for NC, VA, GA, with a preference for nurseries that are closer to TN if possible. You should be able to find a number in the blue ridge / piedmont areas.

Note that the website does not address whether the source is a good company to do business with. I would check GW for that. In addition, some will be wholesale - not sure if you have access to those.

If you have a green thumb, then I might suggest starting some from seed - you still have some time to set containers outside for this spring, especially if the seed is wild collected or has been pre-chilled. You can get a lot more plants for less $ this way. Otherwise, ask the companies if they sell plugs. If all else fails, and you wind up buying retail nursery gallon-size containers, these can often be divided into plug-size clumps using a sharp serrated knife.

Here is a link that might be useful: TN native plant suppliers

Most of the grasses suggested will get quite tall...I don't think that's what you want? A lawn maintenance man once told me that there were no grasslands in this part of the country...we live in the woods, not on the prairie. He thought folks were nuts for having lawns, even though that's how he made a living. Festucas are the only short grasses that I can suggest...mondo and liriope are ubiquitous and not native, but are SO useful.

I think nativeplanter hit the nail on the head.

I highly recommend either little bluestem or broomsedge. I currently do exactly what you are looking to do in an old field about 2 acres in size, with broomsedge. I love the way the orange grass looks through the fall and winter, and love the way it sounds when the wind blows through it.

SpringtimeHomes,
Have you found any seeds yet? I have some native grass seeds I can share to get you started.