Personally, I think it would be best to start as more inclusive so we have more activity. We used to have a Georgia Forum but it disappeared due to inactivity. The Tennessee Forum only has one thread that has had any posts since July 2015 and half of the posts in that thread are from Ken aka "drdawg", who lives in Mississippi. To me, that indicates that the more areas in the southeast that we include, the better chance that we have of thriving. Also, I'm guessing that Dave only likes to add forums when he thinks that there is a good chance of regular activity. A bigger pool of people would increase the odds of that activity.
Actually, some of my favorite gardening advice comes from people as far west as East Texas since the climate is still similar enough for the advice to be very helpful here. I love all of the Greg Grant plant introductions that I've tried so far.
I'd also enjoy hearing from people across the world who live in a similar climate such as parts of Argentina, southeastern China, parts of Japan, etc. After all, it is due to the similarity of climate that some of the Southeast's (USA) best performing garden plants come from these areas.
@Dave , do you have any thoughts on this proposal?
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Barb, my grandparents had Mountain Laurels (Kalmia) growing just like that in their woods. They were farther north than you, though. There was a horseshoe bend in the creek with at least a 50 foot straight drop from the backyard to the creek. The Mountain Laurels grew right on the edges, leaning out from the cliff and into the sun. They were gorgeous! It was frustrating not being able to view the flowers up close but it would have been way to easy to fall off the cliff into the creek and rocks below.
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A Magnolia would be a lovely microbadge (although the mosquito suggestion was funnier!
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A fat mosquito would fit for most of the Southeastern Gardening area. 
A much better suggestion. I'd vote for the southern Magnolia. 
