This week's report is written by Don Hunter. The photos are
selected from Don's
facebook album.
Most people awoke on this morning to the sound of light
rain, enough rain to make the gutters sing, but still, twenty-one brave souls
ventured out and gathered at the arbor and were rewarded with a clearing sky
and comfortable temperatures by the time Hugh called for readings. Hugh,
once again, through either magical incantations or sheer mind over matter, had managed to defeat the weatherman!
We had two readings today, the first provided by Ed Wilde, who read from
William Bartram’s “Bartram’s Travels”, which describe his travels in the
American South and encounters with American Indians between 1773 and 1777. (The book's full title is “Travels through North and South Carolina, Georgia, East and West
Florida, the Cherokee Country, the Extensive Territories of the Muscogulges or
Creek Confederacy, and the Country of the Chactaws. Containing an Account of
the Soil and Natural Productions of Those Regions; Together with Observations
on the Manners of the Indians.”)
“Leaving
the pleasant town of Wrightsborough, we continued eight or nine miles through a
fertile plain and high forest, to the north branch of the Little River, being
the largest of the two, crossing which, we entered an extensive fertile plain,
bordering on the river, and shaded by trees of vast growth, which at once spoke
of its fertility. Continuing some time
through these shady groves, the scene opens, and discloses to view the most
magnificent forest I had ever seen. We
rise gradually a sloping bank of twenty or thirty feet in elevation, and
immediately entered this sublime forest; the ground is a perfectly level green
plain, thinly planted by nature with the most stately forest trees, such as the
gigantic black oak (Q. tinctoria), Liriodendron, Juglans nigra, Platanus,
Juglans exalta, Fagus sylvatica, Ulmus sylvatica, Liquid-amber styraciflua,
whose mighty trunks, seemingly of an equal height, appeared like superb
columns…”
(Ed’s note: I assume “thinly
planted by nature” and “level green plain” meant grass grew between the
trees. For those not up to Latin names
for trees, the forest consisted of black oak, tulip, black walnut, sycamore,
shell bark hickory, beech, elm and sweetgum.)
“…To
keep within the bounds of truth and reality, in describing the magnitude and
grandeur of these trees, would, I fear, fail of credibility; yet, I think I can
assert, that many of the black oaks measured, eight, nine, ten and eleven feet
in diameter five feet above the ground, as we measured several that were above
thirty feet girth, and from whence they ascend perfectly straight, with a
gradual taper, forty or fifty feet to the limbs; but, below five or six feet,
these trunks would measure a third more in circumference, on account of the
projecting jambs, or supports, which are, more or less, according to the number
of horizontal roots, that they arise from; the Tulip tree, Liquidamber, and
Beech, were equally stately.”
Ed also provided the following facts regarding the Black Oak
(Q. velutina):
·
The state record Black Oak is on the property of
Our Lady of Perpetual Help, in the shadows of the old Fulton County Stadium, in
Atlanta, Geogia. It is 7.5 feet in
diameter, 105 feet tall and has a crown spread of 135 feet.
·
The U.S. champion Black Oak is 9.5 feet in diameter,
is 78 feet tall and has a 89 foot spread.
The second reading was provided by Don Hunter. Don read a poem of his own writing, “Ode to the Common Crepe Myrtle”.
Gift of Michaux, brought to us from a place
far in the East,
Your beauty, ere it be Summer or Fall, is
something upon which the eyes can feast.
Your trunks, there may be many, grow both
sinewy and smooth, reaching up in graceful lines that bring happiness to my
heart.
It is a joy to touch you, to feel your cool
bark and to marvel at its feel beneath my hands, it’s mottled patterns doth
truly be nature’s art.
In Summer, your flowers are grand, in shades
of purple, red and pink and, oh yes, even white!
Your crenulated flowers glow so brightly as
to make one think that for just a moment they could burst, yes they might.
And when Summer finally draws to a close, and
your flowers are shed,
You, chameleon like, turn your leaves from
green to yellow and orange and red.
Yes, come Fall, your leaves all aglow, as
brilliant and resplendent as any could be,
You are as beautiful a sight as one could
see.
So go on and shine and glow as bright as you
can ‘til Fall’s great blustery winds strip you bare,
Your graceful trunks and limbs alone holding
sentinel ‘til Winter ends and Spring is again in the air.
After the readings, we left the
arbor, walking past the Visitor Center and up to the Upper Parking Lot, where
we walked the Orange Trail. We briefly wandered
off the Orange Trail, with a detour up Copperhead Creek, to view the folding in
several rock outcrops (described by Dr. Gilles Allard in the Purple/Orange
Trail booklet). We returned to the
Orange Trail, where we walked to the foot bridge and crossed the stream,
heading back up to the Flower Gardens and the Visitor Center. The main emphasis again today was identifying
the forest communities, based on the observed flora and other characteristics
and criteria.
 | |
| Sourwood |
Heading past the Visitor Center
fountain, Hugh pointed out the Oak Leafed Hydrangea (Hydrangea quercifolia),
which is beginning to turn red. As we
continued on, we came upon a large Sourwood (Oxydendrum arboreum) below the Upper Parking Lot, as well as many
of them around the lots.
As we moved into the forest, at
the head of the Orange Trail, we were reminded that we would be looking at the
forest communities on our walk today.
The upper section of the Orange Trail is a Successional Forest. The first trees to establish are the Short
Leaf and Loblolly pines. We see many of
the Short Leaf pines in the canopy, as well as several dead and fallen pines on
the forest floor. The presence of many
fallen pines indicates that the succession is changing over to oaks, entering
the climax forest stage. In the developing forest, pines are generally followed by Sumac and
Tulip trees, in the order of succession.
The tulip trees remain in the canopy, even as it becomes more oak
populated. As we made our way down the
trail, we were on an east facing slope and noticed many large American Beech
trees (Fagus grandifolia), indicating
a mesic setting.
 | ||
| Hugh points out pitch pits in bark of Shortleaf Pine |
We made a brief stop at a Short
Leaf Pine (Pinus echinata) to point
out the distinctive, glands of the bark plates, which appear as small
pits. The needles of the Short Leaf Pine
are present as two needles to the bundle at the tips of the limbs. Also, with respect to the pine cones, the
Loblolly cones have “prickles”, whereas, the Short Leaf cones do not. At this location, we also saw a Sparkleberry
tree (Vaccinium arboretum), growing
in the middle of the trail, with it’s smooth bark and green foliage in the top
of the tree.
A little further down the trail,
someone pointed out a cluster of Oyster Mushrooms (Pleurotus ostreatus) and a cluster of what appeared to be small
Oyster Mushrooms growing in a cranny near the base of a large tree. While viewing the mushrooms, we discovered
that there was an active yellow jacket nest in the ground, no more than two or
three feet from the base of a tree. We
survived with no one getting stung! Also here was a small patch of the emerging
leaves of Tipularia discolor, or the
Crane Fly Orchid.
Next, we came upon another rangy
Sourwood tree and a High Bush Blueberry (Vaccinium
corymbosum) with it’s distinctive bright green colored new growth limbs and
twigs.
After moving through the gate we
stopped at a Black Cherry tree (Prunus serotina), with Emily’s “burnt potato chip” bark but,
upon closer examination, the typical horizontal lines associated with Black
Cherry bark were still visible on the bark plates. This tree is also associated with the
successional forest and usually comes along with the tulip poplar and sweet
gum. Also of note at this location was
that the moss on this tree was, as the old adage says, on the north side of the
tree.
 | |
| Headward erosion |
Not far down the trail, is the
beginning of the stream bed. The head of
the stream bed is advancing up the ridge, as headward erosion is
occurring. The soil forming the banks of
the deep ditch are more or less sloughing off, generally during significant
rain events, the material being carried downstream to the river.
Just past a small Water Oak (Quercus nigra), a small sedge was found
growing along the edge of the trail. We
were reminded that “sedges have edges” when trying to determine if a suspect
plant is a grass or a sedge. Below the
sedge we saw a Climbing Hydrangea (Decumaria
barbara) on a Red Oak tree (Quercus
rubra) and a Lance Leafed Smilax AKA Lance Leaved Greenbrier (Smilax smallii) on a Hop Hornbeam tree
(Ostrya
virginiana).
At the informational sign at this
location, we are reminded that this is a successional forest, though it is far
along in the process of succession, with many of the larger trees growing up
into the canopy. Along the trail we saw
Wood Oats (Chasmanthium sessiliflorum), a smaller cousin to the River Oats (Avis’ Fish on a pole!),
with it’s very small flowers and seeds all along the stem.
 | |
| Southern Grape Fern with fertile frond |
Next we had a lesson on
distinguishing between the Southern Grape Fern and Rattlesnake Fern, both found
in relative abundance along the trails at the Bot Gardens. Both have similar looking fertile fronds but the
Southern Grape Fern (Botrychium
biternatum) which we saw at this location, has a fertile frond that grows
from the ground, along with the other fronds, whereas the fertile frond of the
Rattlesnake Fern, as well as the other fronds, grow from a stem above the
ground. The leaves comprising the fronds
of the Rattlesnake Fern are also somewhat finer than those of the Southern
Grape Fern. Both ferns are fertile
during an overlapping period in the late Summer so they can be mistaken, if not
careful.
To our right, as we walked down
the trail, a spring could be seen breaking out onto the surface and quickly
joining the, at this point, drier main stream bed, providing a significant
amount of the total flow. This is an
obvious phenomenon but many times, streams such as the one along the Orange
Trail seem to magically get larger, with respect to the amount of flow present,
without contributions such as the spring.
This is not magic, of course, but science. In hydrologic terms, streams such as this,
flowing over generally unconsolidated material, are classified as either
“gaining” or “losing” streams. Where
the water table is deep, surface water being conveyed by the stream will
gradually leave the stream by migrating downward into the bed of the stream and
seeking the water table found below at depth.
But where the water table is shallow, as is frequently the case as you
lose elevation along a smaller stream as it nears a larger stream (our case),
the bed of the stream will intersect the water table. When this happens, the water table actually
contributes to stream flow, by welling upward into and through the bed of the
stream.
 | |
| Sycamore fruits ("seed balls") |
We saw a Crossvine (Bignonia capreolata) on a Hop Hornbeam
and passed by a large Sycamore tree (Platanus
occidentalis) , with it’s rough, lower bark and smooth upper bark. A limb tip was seen on the ground below the
tree with it’s spherical seed balls. We
also noticed a Broad Beech Fern (Phegopteris
hexagonoptera), and not far away, a Decumaria,
or wild, climbing hydrangea on a Musclewood (Carpinus caroliniana) next
to the trail. Also seen were Sweet Shrub
(Calycanthus floridus), Piedmont
Azalea (Rhododendron canescens) and
Wild Ginger (Asarum arifolia) along
the banks of the stream.
At the Sitting Bench, we learn,
on the informational sign, that we are in the Ravine and Lower Slopes forest
community and have actually been in it for quite a bit as we made our way down
the trail to this point. Canopy trees
here are Basswood, Beech, Bitternut Hickory, Northern Red Oak and White Oak. The sub-canopy consists of Chalk Maple,
Mulberry, Paw Paw, Redbud, Red Maple, Sweetgum and Umbrella Magnolia (which we
have not seen). The shrub layer is
represented by Bladdernut, Paw Paw, Canadian Buckthorn, Painted Buckeye, Sweet
Shrub and Wild Hydrangea. A Chalk Maple (Acer leucoderme) was noted very near the
informational sign.
 | |
| Differential weathering makes gneiss folds stand out |
 |
| Nice folds in gneiss rock |
At this point, we hiked up the
little side trail that follows a small stream, referred to as Copperhead Creek,
up the hill to see some interesting features in the rock outcrops above the
stream. Retired UGA geology professor,
Dr. Gilles Allard, has described the geology of the Purple and Orange Trails
and this description is included as an appendix to the Botanical Garden’s
pamphlet “The Plant Communities Along the Purple/Orange Trail at the State
Botanical Garden of Georgia”. The
subject rock outcrops are seen high above the small stream approximately 150
feet from the Sitting Bench. Visible in
this outcrop of migmatitic gneiss are small, tight folds in the rock. This can be seen in relatively fresh, broken
surfaces, where the alternating layers of dark and light colored minerals
reveal a wavy pattern of small, tight folds.
It can also be seen in parts of the outcrop that are covered in
moss. The minerals comprising the darker
layers, seen in the fresher rock, are more susceptible to chemical weathering
than those making up the lighter colored layers, which contain quartz and
feldspar. The layers that are more
resistant to chemical weathering stand out in relief as the ridges seen in the
wavy patterns.
 |
| Beechdrops with fruits |
 | |
| Hugh on left; River Cane on right |
A large American Beech
tree can be seen at this outcrop, complete with Beech Drops (Epifagus americana) at its base.
After making our way back to the
Sitting Bench, we continued downstream, seeing River Cane (Arundinaria
gigantea) , a native bamboo, a type of
grass. After a massive privet
eradication effort along the river and the stream, it was hoped that River Cane
would flourish but Box Elder has become more prominent, not necessarily a bad
thing. Beech Drops were also seen here.
 | |
| Liverwort |
Hugh pointed out some liverwort (Conocephalum conicum) growing on a rock
found at waters edge in the stream. Most
liverworts are small, usually from 2–20 millimetres (0.08–0.8 in) wide with
individual plants less than 10 centimetres (4 in) long, so they are often
overlooked. The most familiar liverworts, as we see in the stream here, consist
of a prostrate, flattened, ribbon-like or branching structures called a thallus
(plant body); these liverworts are termed thallose liverworts (Wikipedia).
Further down the stream, Hugh
pointed out scattered wood fragments on the ground, the result of Downy Woodpecker (Picoides pubescens) activity
up in the canopy. Pipsissewa or Spotted
Wintergreen (Chimaphila umbellata) was
also seen here.
 | |
| Combed Toothed Mushroom |
After we crossed the foot bridge
to make our way up the hill to the Flower Garden, was some large leafed
climbing hydrangea (Sp. ?) on a Musclewood.
Prior to leaving the forest, several nice Combed Toothed mushrooms (Hericium coralloides and Hericium ramosum), were seen on a fallen
log.
 | |
| Baccharis in front of bridge |
Immediately after walking out of
the forest, Hugh gathered everyone on the foot bridge into the Flower Garden to
point out the Groundsel Tree (Baccharis
halimifolia), a large flowering shrub growing up from the ground below the
bridge. This is a coastal plain shrub,
which seems to migrating farther north from the coastal area where it is
normally seen.
 | |
| Sycamore Tussock Moth caterpillar |
Before leaving the
bridge, we saw the Fall Webworm caterpillar (Hyphantria cunea) and a Sycamore Tussock Moth caterpillar (Halysidota harrisii).
After making our way into the
Flower Garden the solitary bee “condominium” was pointed out. Hollowed out sections of round limbs are
stacked here and provide a place for the bees to lay their eggs.
After arriving back at the
Visitor Center, we adjorned to Donderos for refreshment and conversation, all
glad that the rain had been so nice to miss us this fine morning.
Summary of Species Seen on this
Ramble:
Flora
Oak Leafed
Hydrangea (Hydrangea quercifolia)
Sourwood (Oxydendrum arboreum)
Short Leaf
Pine (Pinus echinata)
Sparkleberry
tree (Vaccinium arboretum)
Oyster
Mushrooms (Pleurotus ostreatus)
Crane Fly
Orchid (foliage) (Tipularia discolor)
High Bush
Blueberry (Vaccinium corymbosum)
Black Cherry
tree (Prunus serotina)
Water Oak (Quercus nigra)
Climbing
Hydrangea (Decumaria barbara)
Red Oak tree
(Quercus rubra)
Lance Leafed
Smilax AKA Lance Leafed Greenbrier (Smilax
smallii)
Hop Hornbeam
tree (Ostrya virginiana)
Wood Oats (Chasmanthium sessiliflorum)
Southern
Grape Fern (Botrychium biternatum)
Crossvine (Bignonia capreolata)
Sycamore
tree (Platanus occidentalis)
Musclewood (Carpinus caroliniana)
Sweet Shrub
(Calycanthus floridus)
Piedmont
Azalea (Rhododendron canescens)
Chalk Maple
(Acer leucoderme)
American
Beech (Fagus grandifolia)
Beech Drops
(Epifagus Americana)
River Cane (Arundinaria gigantean)
Pipsissewa
or Spotted Wintergreen (Chimaphila
umbellate)
Combed
Toothed mushrooms (Hericium coralloides
and Hericium ramosum)
Broad Beech
Fern (Phegopteris hexagonoptera)
Wild Ginger
(Asarum arifolia)
Groundsel
Tree (Baccharis halimifolia)
Fauna
Downy Woodpecker (Picoides pubescens) (visual evidence)
Fall Webworm
caterpillar (Hyphantria cunea)
Sycamore
Tussock Moth caterpillar (Halysidota
harrisii)
