Well as for this question: " Next, I'll list reasons (the ones that come to mind right now) for and against introducing invasive plants." For the ones you list, 3 is a pretty good one. If it is already here, and already in a heavily altered landscape that will never be natural, then it is alright to use. Number 6 is good, too-since humans have changed everything, these invasive plants have found a niche in the new environment we have created. Nature has a hard time existing where I live, 95% of the county is in intense agriculture, 80% is plowed field of corn and soybeans, so sometimes people's views might be different because what they see on daily basis. Now with high prices of land and commodity prices, even the naturalized species are being destroyed, leaving less room even for the more adaptable species of animals.

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.

Thanks for the info!

For those of you wanting to grow Buddleia/Buddleja, be aware that it is invasive (environmentally damaging) in this area. A large area over at Ijams Nature Center, for instance, is absolutely covered over in this stuff. Some plant catalogs (Plant Delights, for instance) say it's alright to grow invasives as long as you aren't near a natural area. This couldn't be further from the truth and is very irresponsible for them to put out to the public. Buddleia/Buddleja isn't documented to be as much of a problem as some other invasives, but if you just go look at the Mead's Quarry area over at Ijams, you'll have little doubt as to it's environmental impact. There are cultivars that are sterile, or near sterile. Supposedly, they are safe to plant. Apparently even their seedlings, if they have any, are also sterile/near-sterile. So, you should be able to plant these cultivars guilt free: Buddleia/Buddleja 'Blue Chip' Buddleia/Buddleja 'Asian Moon' Buddleia/Buddleja 'Purple Haze' Buddleia/Buddleja 'Ice Chip' (formerly 'White Icing') Buddleia/Buddleja 'Podaras #4' (aka Flutterby Grande Blueberry Cobbler) Buddleia/Buddleja 'Podaras #5' (aka Flutterby Grande Peach Cobbler) Buddleia/Buddleja 'Podaras #2' (aka Flutterby Grande Sweet Marmalade) Buddleia/Buddleja 'Podaras #3' (aka Flutterby Grande Tangerine Dream) Buddleia/Buddleja 'Podaras #1' (aka Flutterby Grande Vanilla) Buddleia/Buddleja 'Podaras #15' (aka Flutterby Petite Snow White) Buddleia/Buddleja 'Podaras #9' (aka Flutterby Pink)