Thursday, December 19, 2013

Rock and Shoals Ramble December 17 2013



This Ramble Report was written by Don Hunter. Don's photo album of the ramble is here. The photos included in this post are all Don's.

On Tuesday, December 17, 2013, twenty-one eager and kindred souls gathered at the Barnett Shoals Elementary School, on Barnett Shoals Road, for a ramble through the Rock and Shoals Natural Area, organized by Ramblers Joan and Sandra.  It was probably still in the 30’s as we all arrived and mingled a bit at the school, enjoying hot coffee, chocolate banana bread, cranberry bread, both still warm from the oven, and mixed fruit, all kindly provided by Joan and Sandra.  


The group assembled at the end of Rock & Shoals Dr.
 At the appointed time, we carpooled over to the parking area at the end of Rock and Shoals Drive, where Hugh led us through the woods and out into the beautiful outcrop area.  It was, for many of us, the first time to see this and we were all in awe at the beauty we saw upon entering the first clearing.  Hugh pointed out, as we moved along the trail, that much of the area around the outcrops was originally terraced for cotton farming.  We also learned that the area was once used as a local dump site for discarded household items.  There is still evidence, to this day, of the dumping, in the form of rusted car doors, pieces of glass and other discarded items, but an organized clean-up effort has restored most of the site to its original glory.

As we entered the outcrop area, we saw that needle grass, along with Little Bluestem (Schizachyrium scoparium), were the main grasses found in the clearings, dominated by the relatively short but robust Eastern Red Cedar (Juniperus virginiana) trees, with a smattering of deciduous trees, such as small oaks and Sweetgum (Liquidambar styraciflua).  The exposed rocks in the
Gneissly folded "granite"
outcrops are often described as “granitic”, similar in composition to Stone Mountain and other large plutonic outcrops, such as Panola and Arabia Mountains, found east of Atlanta.  These, and the rocks of the Rock and Shoals Natural Area, are not actually granite but are comprised of a metamorphic rock called migmatitic gneiss or migmatite. Migmatites were metamorphosed at higher temperatures than gneiss but not sufficiently melted to become granite.  You will see, if you look carefully as you walk across many of the bare rock areas, relic textures such as folds, just as we saw earlier in the fall in the rock outcrops along the banks of Copperhead Creek at the Botanical Garden.  

 The outcrops are rock islands in a sea of sometimes broad expanses of grass and lush beds of a variety of mosses and small shrubs. Near the first outcrops after exiting the forest, one can find, in early spring, in the grass among a few of the nearby Eastern Red Cedars, Ten-petal Thimbleweed (Anemone berlandieri), a rare plant found only at the Rock and Shoals Natural Area and at a few locations in Arkansas.  The blooms are generally present for a week or less so you have to be lucky to catch this one blooming.
 
Resurrection Moss with frost removed
As we made our way down the trail, we stopped and observed the first of many lichens, the Peppered Rock-shield lichen (Xanthoparmelia conspersa), as well as Resurrection Moss (Grimmia laevigata).  The Resurrection Moss, as found, was a dusky, gray green color, but is black when completely dried out.  The color we saw was due to lingering frost from last nights low temperatures. Joan dribbled some water over a frosted patch and we saw just how rapidly the true color could reappear. 

Sandwort & frosty grass blades
Nearby, as we continued on, we saw the first of the very abundant Sandwort (Minuartia uniflora), popping up in the damp to wet shallow depressions in the rock.  Sandwort and Elf Orpine (Diamorpha smallii) both occupy the shallow depressions and are annually subjected to very harsh conditions, ranging from the sub-freezing cold of winter and summer temperatures which can range above 100 degrees F.  They form rosettes in the wintertime and in March, when daily temperatures are more or less consistently warmer, the shallow depressions become veritable gardens, which, by mid-April are spectacular in their beauty.  Even though we saw the Sandwort beginning to emerge during the ramble, it was still a bit early to see first evidence of the Elf Orpine.

Bird's Nest Mushroom
As we made our way across the outcrop, Hugh took us off-trail over to an Eastern Red Cedar to see a sight we would have surely missed without his help.  Here we saw the spectacular and miniscule White-egg Bird’s Nest mushroom (Crucibulum laeve) The "nest" is only a little over 1/4 inch in diameter and serves as a "splash cup" to disperse the "eggs," which contain spores. The fruiting use the kinetic energy of falling drops of rain to knock the "eggs" out of the "nest."  The "eggs" inside the bird's nests (technically known as peridioles) have hard waxy shells containing spores, and tend to stick to whatever nearby herbage they land on, thus increasing the odds of being consumed and dispersed by herbivorous animals.  (Wikipedia) 
 
Granite Thorn Lichen

Dixie Reindeer Lichen
Juniper Haircap moss
As we made our way back out on to the trail, we encountered a large patch of Granite Thorn lichen (Cladonia caroliniana) and Dixie Reindeer lichen (Cladonia subtenuis), and not far beyond,
some Juniper Haircap moss (Polytrichum juniperinum), bedazzled with icy crystals. 

Resurrection Ferns
As we arrived at the western extent of the outcrops, we spent considerable time looking for Elf Orpine in the shallow depressions near and along the seeps but failed to see any. As we worked our way past an Eastern Red Cedar, Hugh pointed out a nice cluster of Resurrection Ferns (Pleopeltis polypodioides), high in the tree.  With the fairly recent rains we have had, it was looking nice in it’s “resurrected” state. 
 

Jester lichen
We also visited, for a while, a large patch of Jester lichen (Cladonia leporina), with it’s nice, bulbous red caps.  The Jester lichen, though similar in appearance, differs from its cousin, the British Soldier lichen, being more recumbent than the stiff, upright British Soldier.   




Just beyond and growing, appropriately enough, in the shadow of a large rock was a Hairy Lip-fern (Cheilanthes lanosa), which
Hairy Lip fern
loves shade, and Hairy Spiderwort (Tradescantia hirsuticaulis).  Rosemary was curious about the name for the Hairy Lip-fern.  According to Hugh, the Latin derivation of the name is Cheilanthes = lip and  flower and lanosa = woolly, which doesn’t fully  answer the question regarding the hairy lip.  It turns out that the sori, the reproductive bodies, are located on the margin (lip) of the pinnae (leaves) for all of ferns in this genus, hence the name "lip fern."  There are hairs all over the fern, which is why it is called hairy or woolly.

Hugh also pointed out two locations where blasting had occurred in an effort to determine if quarrying was practically and economically feasible.  Fortunately, for us, the results were apparently not encouraging for those wishing to pursue this venture.
 
Reindeer lichen (Cladonia rangiferina), and more Granite Thorn lichen were seen, as well as the puffy Olive lichen (Cladonia strepsilis) as we made our way back across the outcrop. The Reindeer lichen is distinguished, in part, from the Dixie Reindeer lichen, being much whiter (lighter) in appearance.  In this area, Hugh pointed out that another rare plant, the Granite Stonecrop (Sedum pusillum) could be found here, though it is too early to see it, as it will be blooming in the spring.

We walked past a large clump of dead Yellow Eyed Grass (Xyris sp.), with the stems and roundish, knobby seed heads.  They, as well as the rare Dwarf Hatpin (Eriocaulon koernickianum) disappeared, for a while after the last severe drought, but have reappeared.  More Yellow Eyed Grass was seen, a little further on, along with dried Confederate Daisies (Helianthus porter) and an unidentified coarse bladed grass.

Looking for Pixies
We had the good fortune, before we exited the
Found some!
outcrops, to see a large group of Pixie Cup lichens (Cladonia sp.) growing in the midst of a large patch of moss. After viewing the Pixie Cups, we worked our way back across the outcrops and back to the cars, where we loaded up and headed back to the school to continue socializing, enjoying the cake (totally consumed), fruit, coffee and conversation.

Summary of species observed on the Ramble:
Needle grass (Piptochatium avenaceum)
Little Bluestem (Schizachyrium scoparium)
Eastern Red Cedar (Juniperus virginiana)
Sweetgum (Liquidambar styraciflua)
Tenpetal Thimbleweed  (Anemone berlandieri)
Peppered Rock-shield lichen (Xanthoparmelia conspersa)
Resurrection Moss (Grimmia laevigata)
Sandwort (Minuartia uniflora)
White-egg Bird’s Nest mushroom (Crucibulum laeve)
Granite Thorn lichen (Cladonia caroliniana)
Dixie Reindeer lichen (Cladonia subtenuis)
Juniper Haircap moss (Polytrichum juniperinum)
Resurrection Fern (Pleopeltis polypodioides)
Jester lichen (Cladonia leporina)
Hairy Lip-fern (Cheilanthes lanosa)
Hairy Spiderwort (Tradescantia hirsuticaulis)
Reindeer lichen (Cladonia rangiferina)
Olive lichen (Cladonia strepsilis)
Yellow Eyed Grass (Xyris sp.)
Pixie Cup lichens (Cladonia sp.)
Prickly Pear Cactus (Opuntia humifusa.)


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