Chert Barrens, Wildcat Glades, opposing side of shoal creek on the chert shelf.
It’s actually baffling to me how little chert is known to be removed from this site, I don’t think its clear why that is since it was considered extremely valuable for stone tool crafting. knapping chert to make specific tools was a common practice until the later section of the 1800′s by both Native Americans and European settlers. Flint stone and Chert stone have a specific conchoidal fracture path when striked and appear similar to other glass fracturing due to the high silica.
Silica is also the reason why these shelves are aggressively angular instead of unercut to rounded flush from water movement, since silica is insoluble.
As a heat insulator, chert tends to be harsh and very hot during summer, making this habitat xeric and very exposed in many parts.
While Joplin MO. sits pretty far from the Texas and OK border we see many of the same plants land locked at this location and other near by barrens due to their spread during the early Holocene’s xerothermic interval in an era post glaciation where temps became warm and climate was dry. In a sense these can be considered refugium.
Both Phemeranthus parviflorus and Phemeranthus calycinus overlap in the barrens here.
Phemeranthus parviflorus (small flowered) and Phemeranthus calycinus (large flowered) are distinguishable more readily from flower size, otherwise you have to go off of stature. P. parviflorus is less tall and much less elongate as seen in the picture. As for P. calycinus
Here is a multibranched elongate specimen photographed from https://www.illinoiswildflowers.info/prairie/plantx/lf_rockpink.htm
The mossy fern looking lad is a semi-xeric spike moss: Selaginella rupestris, ledge spike moss.
Now, I think the range maps for this are very wrong. Texas has plenty of these in their northern counties and bonap says they are not in the Ouachita and in the Wichita Mountains which is solid malarchy. I plan on looking for this lad in big barrens next time I go.
Often surrounded by a layer of waterlogged biocrust stabilized sediment and Polytrichum commune is Opuntia humifusa
Ferns are often more xeric and exposure adapted than we give them credit for. Ebony spleenwort is obviously the most common fern just about anywhere; but, the calcareous Asplenium trichomanes subsp. quadrivalens and the crack loving Myriopteris gracilis are always mind blowing to see in different habitats.
