I think this is Lotebush, as opposed to Condalia viridis which was also in this tangle of brush. I had inadvertently included the image of the drupe (2nd image here) with a different shrub which was ID by @joshua_tx as the latter species. Hope I got this right!
Dolan Falls Preserve is owned by The Nature Conservancy and is not open to the public. Access is through special permission only. The preserve is adjacent to Devil's River State Natural Area, which is open to the public on a restricted schedule.
A lone cluster out in the middle of a meadow with lots of tall grass and weeds. I didn't feel like wading through the tall grass and weeds for a closer shot, since I was wearing shorts with no boots and this is rattlesnake and cottonmouth country. However, I have seen others of this species in the area, including the next observation seen only a few hundred feet away.