Saltcedar, that's it! I did some web surfing and you're absolutely right. We're within walking distance from Ga marshland, so, Baccharis halimifolia, (Groundsel, Sea Myrtle, Consumption Weed) makes perfect sense for our area. I think that this shrub may get too big for the waterfall to handle but I'm going to leave it there until it blooms in late summer or early fall. Now I have names for both plants on the waterfall. Thank you soooooo...much, Bboy and Saltcedar. Love this forum!

Out here there's an upland species, Baccharis pilularis (coyote brush), Wildflowergma, that looks similar to your B. halimifolia. However, Baccharis salicifolia (mule fat) is usually found in wetlands. (I was on a marsh restoration job once where the person in charge of getting materials ordered the upland species by mistake THREE times...sigh). B. salicifolia does look very different from both, except for similarities in flowers and being dioecious.

Hmm, so I guess it was down to Baccharis neglecta, salicifolia, salicina, or halimifolia. But, the leaves of Baccharis salicina look too wide. Baccharis pilularis (top), salicina (middle), salicifolia (bottom) So, this led most likely to Baccharis salicifolia. Just refreshing this debate because I found another similar specimen today with very narrow leaves (almost like Rosemary):

seedmoney - thank you SO much for the seeds, just got them in today. I wish you were here when I shouted "YES!" at the dinner table. My husband raised his eyebrow at me. The extras are wonderful. I will be sure to send you pictures.