South Carolina Sites    Jess Riddle
  Nov 10, 2004 09:21 PST 
   Bob Leverett wrote:  In terms of the areas that you regularly visit, what are your thoughts on the division sites and sub-sites for the purpose of applying Rucker height, diameter, and height/diameter ratios? I ask this question, not because I can't infer from the detail you provide how you are "seeing" the sites, but because I've been thinking about developing the concept of breaking down the politically-defined sites in Massachusetts into sub-sites, where a variety of terrain types are represented.   

In general, I see little reason to breaking down the SC sites into smaller
units. That position results from the fact that multiple interfaces
coincide to naturally delineate most of the sites. For example, at
Wadakoe Mountain, geology, topography, and forest type all correlate well
to form the natural boundaries at the site. The corelations are not
perfect as seen in the gradual transition of the forest types on the north
and west lower slopes before the natural boundary of the cleared fields is
reached. In that case, the field border defines the site edge since
disturbance history, soil type, and topography all coincide as the fields
only occupy the large flats along Eastatoe Creek, so the gradual
transition of the forest does not represent a significant challenge in
defining the site. The mountain could still be subdivided on the basis of
stream basins or one area that was likely farmed could be singled out;
however, the similarity of topography, the distributions of unusual
species, and extent of unusual geology cause me to still think of the site
as a single unit.

Situations in the Brevard Fault Zone leave greater room for flexibility in
determining site boundaries. The interface of a large plateau and steep
slopes coincides with changes in geology and forest type to precisely
define the upper edge of the sites. Since the soil nutrients fueling the
high growth of the area appear to be derived only from bedrock underlying
the steep slopes, the base of the steep slopes would seem like a natural
boundary; however, the transition to the gentle slopes of the adjacent
piedmont is gradual, and the downhill movement of material from the steep
slopes results in a continuum of influence on adjacent soils. In some
cases, resent human disturbance creates a clear edge, sometimes coinciding
with the Forest Service property boundary, but for much of the area, I
have been satisfied with an approximate boundary. The other question with
demarcating the sites in the faults zone is where does one section of the
fault end and the next begin. An extension of the plateau of Station
Mountain separates Station Cove from the series of coves surrounding
Tamassee Knob, so a physical barrier separates the sites; however, the
sites are closely related in geology, similar in forest type, and the
spatial separation is relatively small, so a case for either
distinguishing or grouping the sites could easily be made. The Lee Branch
area, which shows a gradual trend in forest type along a north-south axis,
is separated from Station Cove by a slightly large ridge than separates
Station Cove and Tamassee Knob. The area is geologically closely related
to Station Cove and the forest at the north end bears a strong
resemblance, but significant differences in the forest exist even in the
most similar sections; Hence, I've generally treated the entire Lee Branch
area as a separate site.
Individual coves present a convenient way to subdivide either Lee Branch
or Tamassee Knob. Some argument could be made for that practice in the
Lee Branch area on the basis of the apparent gradient in cove richness
along a geographical axis. So far, I have not reported the site in that
fashion since the transition between coves is gradual, so any grouping
would likely be arbitrary. At Tamassee Knob, each cove has a distinctive
mix of tree species and canopy height, but adjacent coves do not vary in a
consistent fashion, so the area has not been subdivided. Comparing
individual coves in the could present a somewhat controlled method for
looking at the effects of aspect and degree on topographic sheltering on
the canopy structure, but differences in area and species richness could
obscure differences. The best argument for a subsite could probably be
made for the largest cove in the area. The cove has a somewhat different
structure, is at the mixed mesophytic end of the gradient of forest types
present in the area, and has one of the few due NE aspects in the area.
The cove could provide a good comparison to station cove due to
similarities in size, topographic sheltering, age distributions, and
species occurrence patterns.

This is probably less general than what you were looking for, but
hopefully enough similarities exist with MTSF to generate some new ideas
to apply to that area.

Jess Riddle
Re:  South Carolina Sites    Jess Riddle
  Nov 15, 2004 06:27 PST 
  Bob Leverett wrote:  Now to South Carolina? Jess, what is SC's current Rucker index? How does it compare to: (1) your best mounatin property, (2) Congaree?       

The Rucker Indices for the tallest piedmont site in SC, the tallest
mountain site in SC, and the state of South Carolina are followed by a
discussion of that Rucker Indices of superlative sites versus the Rucker
Indices of their host states.
Species listed by first two letters of genus and first two letters of
specific epithet.

Congaree Swamp NP

PITA 167.2 Pinus taeda = loblolly pine
LIST 157.1 Liquidambar styraciflua = sweetgum
QUPA 154.0 Quercus pagoda = cherrybark oak
PLOC 144.0 Platanus occidentalis = sycamore
TADI 141.0 Taxodium distichum = baldcypress
ULAM 135.0 Ulmus americana = American elm
QUMI 132.8 Quercus michauxii = swamp chestnut oak
PODE 131.0 Populus deltoides = eastern cottonwood
QULY 131.0 Quercus lyrata = overcup oak
DIVI 126.9 Diospyrus virginiana = persimmon

RI 142.00

Central Brevard Fault Zone

LITU 170.2 Tamassee Knob Lirodendron tulipifera = tuliptree
CAGL 168.2 Lee Branch Carya glabra = pignut hickory
CACO 154.2 Station Cove Carya cordiformis = bitternut hickory
QURU 150.0 Lee Branch Quercus rubra = northern red oak
QUMO 143.9 Tamassee Knob Quercus montana (Q. prinus) = chestnut oak
ROPS 143.4 Tamassee Knob Robinia pseudoacacia = black locust
QUAL 141.8 Station Cove Quercus alba = white oak
LIST 141.4 Tamassee Knob Liquidambar styraciflua = sweetgum
ULRU 141.3 Station Cove Ulmus rubra = slippery elm
PIEC 139.9 Tamassee Knob Pinus echinata = shortleaf pine

RI 149.43

South Carolina

LITU 170.2 Tamassee Knob Lirodendron tulipifera = tuliptree
PIST 168.9 Walhalla Fish Hatchery (E. Fork) Pinus strobus = estern white
TSCA 168.9 East Fork Chattooga River Tsuga canadenis = eastern hemlock
CAGL 168.2 Lee Branch Carya glabra = pignut hickory
PITA 167.2 Congaree Swamp NP Pinus taeda = loblolly pine
LIST 157.1 Congaree Swamp NP Liquidambar styraciflua = sweetgum
CACO 154.2 Station Cove Carya cordiformis = bitternut hickory
QUPA 154.0 Congaree Swamp NP Quercus pagoda = cherrybark oak
FRAM 153.4 Wadakoe Mountain Fraxinus americana = white ash
QURU 152.9 Whitewater River Quercus rubra = northern red oak

RI 161.50

State vs Congaree. (161.5/142.00-1) x 100 = 13.7%
State vs Brevard Belt (161.5/149.43-1) x 100 = 8.1%

Looking at the circumstances necessary for a significant increase in a
Rucker Index, the dominance of MTSF in Massachusetts and the greater
variety of contributing sites in SC do not seem all that surprising. A
state could have a much higher RI than the best site in the state under
one of two conditions or their combination: much taller individuals of
the same species as at the best site grow found elsewhere in the state; or
very tall species that do not grow at the best site grow elsewhere in the

How likely is it that top ten species at the best site would all approach
their regional maxima? Several months ago, Colby Rucker posted a well
thought out argument for the best site for a species being the one that
the species is best adapted to, where it has the greatest competitive
advantage, and that that would usually not coincide with the area of
greatest resource ability. That hypothesis could be interpreted as
implying that height records would require different sites and thus be
quite spread out spatial; however, sites as trees actually use them are
much smaller than any of the areas we have defined them, and disturbances
could shift a specific location from being ideal for one species to being
nearly ideal for another species. Additionally, even our relatively
homogeneous sites contain small but significant variations in moisture
availability, aspect, and soil composition. Consequently, slight
gradients in environmental conditions, microsites, and disturbance
patchiness on a background of high water and soil nutrients, physical
requirements of great height growth of all species, could result in nearly
ideal habitat for several species occurring in a small area that appears
relatively homogeneous.

How likely is it that all of the tallest species in a state would all
occur at one location? The distribution of physiographic provinces within
a state and latitude of the state largely answer that question. Most rich
site support all or nearly all of the tall species in that physiographic
province. However, in other physiographic provinces, the same species may
have vastly different growth potential. For instance, silverbell grows in
the understory along many southeastern piedmont streams, but becomes an
overstory species in the southern Appalachians. Also, in the northeast,
nearly all of the tall species grow well in the mountains; the coastal
plain of the region has few extremely tall species. Conversely, in the
south, a host of bottomland species reach great size in the piedmont and
coastal plain, but cannot survive compete in the mountains.

Going back to the individual sites, MTSF provides excellent growing
conditions for almost all of the mountain species in Massachusetts. In
other regions of the state, sycamore, tuliptree, and cottonwood are the
only additional tall species I know of, and of those I think sycamore is
the only one that is known to challenge the mountain species in height in
that region (have I been paying close enough attention to your e-mails
Bob?). Hence, small improvements in mountain species at other sites and
sycamore are the only avenues left for Massachusetts to increase the
state's Rucker Index over MTSF.

The same general argument applies to Cook SF, but the argument is not
quite as strong. A few broadleaf mountain species, tuliptree in
particular, do not approach their regional maximums in the park, and
lowland species like sycamore and cottonwood reach more impressive heights.

In South Carolina, the tallest species different regions of the state
ensure some of the tallest species of the state stay well separated, so no
one site can achieve the dominance of some of the northeastern sites.
Compounding that divide is the fact that the best conifer and broadleaf
sites in the mountains do not coincide. In spite of those considerations,
the central section of the Brevard Belt still comes within 10% of the
state Rucker Index. That situation highlights the fact that the
second-tier tall species are not that much shorter than the tallest group
of species. 15 feet may seem like a great height difference, but that
length is still less than 10% of the height of the tallest species.

North Carolina has great tree diversity and distinct physiographic
provinces, so the dominance of the Smokies appears to contradict the
pattern established in looking at the other sites. I attribute part of
the dominance simply to the fact that the Smokies are a special area.
Lack of disturbance, and lack of continued disturbance, climate, geology,
and the resultant high diversity all work in favor of the site. The other
part of the smokies dominance is probably an artificial artifact of how we
have set up the situation. The NC side of the park contains several
distinct high growth areas that are separated by areas of shorter forest
with different growing conditions, and the high growth regions are spatial
separated by a few miles. If not for the park boundary, we would probably
see the area as having several distinct superlative sites rather than one
large, incomparable site. The other human factor is the paucity of data
we have form the NC piedmont and costal plain. Will Blozan has just
recently found one excellent piedmont site giving a specific example of
the regions potential. How tall can sweetgum, loblolly pine, cherrybark
oak, and shumard oak grow in the state's floodplains.

Zoar Valley's dominance in New York points to some holes in this theory
and the spectacular nature of the site. New York has several distinct
regions, yet Zoar Valley appears to include excellent habitat for all of
the tall hardwood species in the state. The lack of conifers makes the
sites dominance more impressive, but reinforces the fact that the second
tier of tall species really is not that much shorter than the tallest
group of species.

Enough half thought through rambling.

Jess Riddle

RE: Questions for Jess and Will   Will Blozan
  Nov 16, 2004 19:07 PST 


Here are some numbers higher than the lowest you have listed below from my
3/17/97 trip to Congaree that will update the RI a few points. All are
lasered heights.

Shumard oak 138.9'
Bitternut 134.8'
Willow oak 130.5' (not in RI)

New RI= 143.6'

Congaree Swamp NP
PITA 167.2 Pinus taeda = loblolly pine
LIST 157.1 Liquidambar styraciflua = sweetgum
QUPA 154.0 Quercus pagoda = cherrybark oak
PLOC 144.0 Platanus occidentalis = sycamore
TADI 141.0 Taxodium distichum = baldcypress
ULAM 135.0 Ulmus americana = American elm
QUMI 132.8 Quercus michauxii = swamp chestnut oak
PODE 131.0 Populus deltoides = eastern cottonwood
QULY 131.0 Quercus lyrata = overcup oak
DIVI 126.9 Diospyrus virginiana = persimmon
RI 142.00