Camp Branch flows south and west into Opossum Creek shortly
before the
latter empties into the lower Chattooga River. Camp Branch
begins flowing
across a plateau at around 1700' elevation and maintains a low
gradient
before dropping 400' over the last half mile. For most of that
distance
the stream flows over mica schist in Forest Service property.
Prior to
government acquisition of the property, the entire watershed
appears to
have been cleared, and at least one house was located along the
stream.
Species composition varies considerably with topography at the
site. The
stretch of stream with low gradient has a largely shortleaf pine
and
tuliptree canopy with some white oak and an open understory.
White pine
and hemlock dominate the steeper section of stream with a
rhododendron
understory. Adjacent slopes typically have either an open or
mountain
laurel understory with pines dominating on the latter slopes and
white
oak, mockernut hickory, and other oaks dominating on the former
slopes.
Chestnut oak is curiously scarce on the drier slopes and in
general from
the lower Chattooga area.
A geomorphology aside: Currently, the Chattooga River joins with
the
Tallulah River to form the Tugaloo River, which becomes the
Savannah River
and flows to the Atlantic along the Geogia-South Carolina state
line.
However, at one time, the Chattooga flowed into the
Chattahoochee River
and eventually reached the Gulf of Mexico. The Tugaloo flowed
across a
lower plain than the Chattahoochee, and the former river’s
headwaters
eroded progressively farther inland. That erosion caused the
boundary of
the Tugaloo basin to move northwest until the watershed
eventually
intersected the Chattahoochee River slightly downstream of the
confluence
of the Chattooga and Tallulah. That event diverted the water of
the
latter two rivers into the Tugaloo and shifted a section of the
continental divide many miles to the west. That theory, already
well
established by the early 1900’s, explains many topographical
features of
the lower sections of the Tallulah and Chattooga rivers. When
the Tugaloo
captured their waters, the base level of the rivers, the
elevation that
they flow to, was suddenly lowered, so the rate they eroded
their beds was
greatly accelerated. Since the lower Tallulah flows over erosion
flows
over erosion resistant quartzite, the down-cutting of the river
has
produced a dramatic, shear sided gorge with several waterfalls.
Conversely, the lower Chattooga flows over softer mica schist,
so a
smaller gorge, without waterfall, bordered by a relatively flat
plateau
has formed along that river. As the tributaries, such as Camp
Branch and
Cliff Creek, cut into that plateau, they concentrate moisture
and create
sheltered conditions that now support exceptionally tall trees.
Cbh Height Species
8'0" 132.1' Hemlock, Eastern
8'+ 136.3' Hemlock, Eastern
NA 138.4' Hemlock, Eastern
5'7" ~116' Hickory, Mockernut
5'6" 141.6' Hickory, Pignut
7'9" 111.9' Oak, Scarlet
5'4.5" 112.6' Oak, Southern Red
5'11.5" 128.6' Oak, White
7'2" 121.3' Pine, Pitch
6'2" 116.5'+ Pine, Shortleaf
NA 118.0' Pine, Shortleaf
6'3.5" 141.2' Pine, Shortleaf
~6' 142.9' Pine, White
7'7.5" 146.1' Pine, White
8'0" 151.1' Pine, White
10'4" 156.8' Pine, White
6'9"* 158.1' Pine, White
NA 131.9'+ Sweetgum
6'11" 133.6'+ Tuliptree
5'11.5" 136.7'+ Tuliptree
*above 4.5'
[ed note: RI
= 132.2]
The hemlocks are some of the tallest second growth individuals
I’ve seen
of the species; all have pyramidal tops, and small, straight
branches.
All other pignut hickories over 140’ I’ve measured in SC
grow on richer,
hardwood dominated sites. This tree also differs from other
pignuts of
comparable height in having a smaller diameter. The southern red
oak is
the tallest confirmed in SC. Pitch pine is scarce at the site,
but
several shortleaf pines are in the 120 to 125’ range. The
141.2’ tree
becomes the tallest individual of the species documented by
ENTS, and is
clearly taller than the others at the site. Most of the white
pines grow
in a dense stand, and at least a handful of others exceed
150’. In good
years, these pines have grown in height over 3.5’. While none
of the
individual diameters of the white pines are unusual for white
pines of
that height range in the southeast, the spread in diameters is
greater
than typically encountered. The pines overshadow the tuliptrees
at the
site, but at least a few tuliptrees will reach 140’. Assuming
a beech
will reach 105’, a minimal estimate, the Rucker index for the
site stands
at 129.95’.
A few interesting trends are beginning to emerge among the sites
with tall
shortleaf pine. Not surprisingly, all of the sites are along low
elevation mountain streams, which provide easy to access to
moisture and
sheltering from strong wind. The sites are also distributed
across of the
southern edge of the portion of shortleaf pine’s range that
does not
overlap with the range of loblolly pine. Where both species
occur,
loblolly tends to occupy moist sites and shortleaf usually grows
in upland
sites, so loblolly may out compete shortleaf on sites where the
latter
could reach great heights. Of course, that raises the question
of what
prevents loblolly from growing of the moist sites just outside
of its
range, and the conditions that favor great shortleaf height
growth may not
exist in loblolly’s range. Also, some sites we haven’t found
yet may
support both loblolly and tall shortleaf, but it will be
interesting to
watch and see if the pattern established by the first few sites
holds as
more site with tall shortleaf are found.
Until recently, the lower section of Opossum Creek may have
supported
larger trees. The sweetgum and scarlet oak listed above grow
along that
section of creek, but most of the overstory in the area was
destroyed by a
tornado in March 1994. The tornado traveled up the gorge of the
Chattooga
River, then, at the bend in the river, continued straight up
Opossum
Creek. Only a handful of trees over a foot in diameter remain
right along
the creek, and about half of the canopy trees were removed for a
distance
of over 400 feet up the north facing slope. Hardwoods tended to
uproot
while hemlocks snapped off half way up the trunk leaving a
legacy of
bleached, three-foot dbh snags along the creek. Many of the
understory
trees have sent up vertical shoots from bent over trunks, so a
tangle of
blackberry, bent over rhododendron, warped ironwoods, and
tuliptree
samplings. On the forest floor or suspended by rhododendron,
logs from
all species remain intact; ones of softer species now quite soft
while
boles of species with harder wood, such as pignut hickory and
white ash,
still retain much of their bark after ten years. The steep north
facing
slope those logs lie on still supports white ash to 120’ and
beech over
10’ cbh to hit at what grew there a few years earlier. The
size of the
hemlock snags along the creek compares favorably with those on
Camp
Branch, and with the greater sheltering along Opossum Creek they
probably
exceeded 150’.
Jess Riddle
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