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8/18/2019 Gulf Coast Pitcher Plant Bogs
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WARNING CONCERNING COPYRIGHT RESTRICTIONS
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governs the making of photocopies or other reproduction of
copyrighted material.
Under certain conditions specified in the law, libraries and archivesare authorized to furnish a photocopy or other reproduction. One of the
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to be used for any purpose other than private study, scholarship, or
research. If a user later uses a photocopy or reproduction for purpose
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17 USC Section 107
8/18/2019 Gulf Coast Pitcher Plant Bogs
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WARNING CONCERNING COPYRIGHT RESTRICTIONS
The copyright law of the United States (Title 17, United States Code )
governs the making of photocopies or other reproduction of
copyrighted material.
Under certain conditions specified in the law, libraries and archivesare authorized to furnish a photocopy or other reproduction. One of the
specified conditions is that the photocopy or other reproduction is not
to be used for any purpose other than private study, scholarship, or
research. If a user later uses a photocopy or reproduction for purpose
in excess of “fair use”, that user may be liable for copyright
infringement.
17 USC Section 107
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he Gulf Coast Pitcher Plant Bogs
The Gulf Coast Pitcher Plant Bogs
eorge W. Folkerts
One of the continent ’ s most unusual assemblages of organisms depend
n an increasingly rare combination of saturated soil and frequent fire
long the eastern portion of the coastal plain bordering the Gulf of Mexico lie areas harboring
semblage of organisms which, although they have fascinated naturalists for centuries, are sti
completely known. The habitats are commonly called pitcher plant bogs, a name taken from
eir most striking components (Fig. 1). Such sites and similar areas have also been termed mo
ne barrens (Harper 1906), grass-sedge hogs or savannas (Wells 1967), herb bogs (Wharton977), and Pleea- phase savannas (Clewell 1971). They have moreover been classed as shallow
eshwater marshes by Penfound (1952), or among flatwood vegetation types by Gano (1917)
hers.
he term “ bog” has been variously used and defined. In practice, the only characteristics that
ogs have in common is a yielding consistency that causes travelers crossing them on foot to t
“ bog down,” at least in some seasons. The Gulf Coast pitcher plant bogs are not structurally
otically similar to the northern sphagnum bogs, although a few species occur in both habitat
he ecosystems discussed here are largely confined to the Lower Gulf Coast Plain from the
palachicola River valley on the east to the Tangipahoa River on the west, and may be found
100 km inland, as shown in the map on page 265, with a few scattered outlying areas farther
orth. Analogous sites, differing in flora and soil, are found along the Atlantic Coastal Plain an
western Louisiana and eastern Texas.
he Gulf Coast pitcher plant bogs are developed on formations dating from Eocene to Holocen
ge. Topographically, they occupy sites ranging from the sides of rolling hills to areas of very
tle relief. Hillside hogs are dish-shaped depressions in which water seeps down- slope throug
porous soil layer underlaid by a restrictive layer that prevents downward percolation. Bogs ineas with little relief are typically called savannas;
eorge W. Folkerts is Alumni Professor of Zoology Entmology at Aurburn University. He
ceived his B.A. and M.A . from Southern Illinois
niversity, his Ph.D. front Auburn University, and has served on f he
culty of Clemson University. His research has been concentrated in three areas: the
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stematics and ecology of reptiles and amphibians; the
stematics, evolution, and ecology of aquatic beetles; and the ecology of pitcher plant bogs, w
special emphasis on insect pitcher plant
teractions. He is the coauthor, with W. H. Mason, of Environmental Problems: Principles,
eadings, and Comments, now in its second edition (1978). Address: Department of Zoology
ntomology, Auburn University, Auburn, AL 36849.
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ere saturation results from a seasonally high water table. Pitcher plant bogs may also be foun
n stream terraces or at the edges of sinkholes.
all sites movement of water through the substrate is slow. Flooding seldom occurs, but
attered small pools are often present during the wet season. The soils are typically sands, loa
nds, or sandy loams. In recent soil surveys they are mapped mainly as members of the Atmo
yatt, Pansey, Plummer, and Rains series, although some bogs do occur on soils of other serie
he soils are typically strongly acidic, ranging from pH 3.5 to pH 5.0. The acidity results from
e activity of mineral components of the soil, with organic acids contributing little. Although
tcher plant bogs are low-energy wetlands in which flowing water moves very little material,
mount of organic litter that accumulates is small because of frequent fires. Input of nutrients
om outside the bogs is minimal in most cases. Nutrient cycling is therefore dependent on the
ganisms
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esent and on frequent release of nutrients by fire.
he pitcher plant bogs are populated by a variety of vascular herbaceous heliophytes that prod
markable floral displays at various seasons. Many of the plants are essentially restricted to th
abitat. Among these are Bigelowia nudata (Asteraceae), Stokcsia laevis (Asteraceae), Zigade
aberrimus (Liliaceae), Rhexia alifanuus (Melastomaceae), Habenaria inutegra (Orchidaceaeabatia cam panulata (Gentianaceae), several species of Polygala (Polygalaceae), Xyris
Xyridaceae), and Eriocaulonn (Eriocaulaceae), and, most notably, a number of species of
rnivorous plants, including the pitcher plants discussed in detail below. The most prominent
onflowering plants in many bogs are two species of Lycopodium (Lycopodiaceae). Although
ecies of Sphagnum, which is so characteristic of northern bogs, are often present, they are no
ually conspicuous. They seldom form large cushions, and in the absence of open water the m
rming process cannot occur.
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xcept for the insect species associated with pitcher plants of the genus Sarracenia, the fauna
e bogs is poorly known. Means and Moler (1978) noted that small pools in the bogs are anmportant habitat for the larvae of the endangered pine barrens tree frog, Hyla andersonii. The
dd flightless grasshopper, Gymnoscirtetes morsei (Acrididae), appears to be restricted to this
abitat (M. E. Dakin, pers. comm.), as is the spittlebug, Lepyronia angulifera (Cercopidae) (J.
hapin, pers. comm.). Several species of burrowing crayfish of the genera Cambarus and
rocambarus are often abundant and may play a role in bringing leached nutrients to the surfa
nts and earthworms are sometimes common but seem to be less so in bogs where the normal
ycles of moisture and fire occur. Bamforth (1976) sampled fungi, bacteria, and protozoa in
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utheastern Louisiana and found populations generally lower in soil surrounding the roots of
ants in bog sites than in other habitats. The general absence of surface litter results in a spars
ter fauna in the bogs as contrasted with areas that do not burn as frequently.
arnivorous plants
owhere on the continent and perhaps nowhere in the world can one find a diversity of
rnivorous plants equaling that in the pitcher plant bogs. Well over half of the approximately
rty-five North American carnivorous species occur along the Gulf Coast, with as many as
irteen species in four genera found in a single bog. Even extensively disturbed sites often
arbor four or five species.
he works of Darwin (1899) and Lloyd (1942) include information on some of the carnivorou
ecies inhabiting the bogs, and more recently Schnell (1976) has described the North Americ
rms in a popular work. However, the details of the evolution and ecology of the carnivorous
ecies remain unclear. In the bogs, the carnivorous flora include species of sundews (Drosera
roseraceae), bladderworts (Litricularia: Lentibulariaceae), butterworts (Pinguicula:entibulariaceae), and pitcher plants (Sarracenia: Sarraceniaceae).
olerance of both fire and soil saturation characterizes the carnivorous species, but the exact ro
at carnivory plays in their ability to survive in the bogs is not fully understood. It has long be
ypothesized (Darwin 1899; Lloyd 1942) that absorption of prey products supplements nutrien
the soil, allowing carnivorous species to compete in nutrient-poor habitats. Plummer (1963)
und that soils in carnivorous plant habitats in Georgia were low in calcium, potassium, and
agnesium, but not exceptionally low in phosphorus. He conjectured that the plants benefit m
om
ineral ions than from nitrogenous compounds derived from their prey. Eleutarius and Jones
969) examined bog soils in Mississippi and found no deficiencies in nitrogen, phosphorus, o
otassium. When they applied 6-12-12 fertilizer and ammonium nitrate, productivity in
arracenia alata actually declined. Christensen (1976) fed insects to S. flava and found no
dication of a resulting increase in concentrations of calcium, magnesium, or potassium in lea
ssue, although levels of nitrogen and phosphorus were significantly higher than those of
ontrols. He concluded that carnivory might enhance plant nutrition on soils deficient in nitrog
nd phosphorus.ttle consideration has been given to the possible role that the availability of micronutrients m
ave played in the evolution of carnivory. Soil scientists have long known that the availability
olybdenum, a trace element essential for plant metabolism, is very low at low pH values suc
typically exist in the bogs (Jones 1957). With our present state of knowledge it could he
ontended that supplementation of the molybdenum supply is a major benefit resulting from th
henomenon of carnivory. A host of other possibilities remain. Bell (pers. comm.) and
hristensen (1976) have pointed out that the breakdown of prey detritus from decaying pitche
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ay serve to fertilize the soil in the vicinity of the plant.
is possible that carnivory may be important only under conditions of nutrient stress that may
ccur relatively infrequently. It is known that levels of nutrients decrease in the bogs during th
owing season (Eleutarius and Jones 1969; Plummer 1963). Several years without fire may
duce nutrient levels sufficiently to make absorption from prey a significant factor in survival
nd competition.
he genus Sarracenia
he most diverse group of carnivorous plants in the bogs is the pitcher plants of the family
arraceniaceae. Only members of the genus Sarracenia occur in the southeastern United State
he western pitcher plant, Darlingtoma californica, also known as the cobra plant, is restricted
e Pacific Northwest, and the six species of the primitive genus Heliamphora are endemic to
uyana highlands of northern South America. The Old World pitcher plants (Nepenthes:
epenthaceae) are not closely related to the New World forms (DeBuhr 1975). Seven or eight
ecies of Sarracenia (Figs. 2 and 3), depending on the taxonomic viewpoint, are present alone Gulf Coast (McDaniel 1971; Case and Case 1976; Schnell 1977).
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he southeastern pitcher plants produce leaves — the pitchers — each year from perennial
nderground rhizomes or rootstocks. The pitchers, which function as pitfall traps, are tubular,ossess downward-pointing hairs on the interior surface, and secrete a fluid containing digesti
nzymes. They capture a variety of insects and other small animals, which are attracted to nect
creted by glands near the pitcher orifice. Reproduction is typically by seeds produced from
owers borne in the spring, hut may also occur by fragmentation of the rhizomes.
esource partitioning allows coexistence among species that occur together. Hypothetically,
rnivorous plants sharing the same habitat should demonstrate prey partitioning similar to tha
und among animal carnivores, and there is evidence of this among Sarracenia species. Fish
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976) has noted that S . minor in Florida seems to capture mainly ants, T. C. Gibson (pers.
omm.) has found evidence of prey partitioning among several Sarracenia species he is study
the Florida panhandle. My own preliminary studies indicate that S . purpurea obtains a
ectrum of prey species quite different from that of other pitcher plants, often capturing
gnificant numbers of grasshoppers, crickets, and snails. Microhabitat segregation exists amon
ecies in the same bog and may influence the types of prey obtained. For instance, along the
ulf Coast S. leucophylla occupies wetter sites than S. flazna, and S . purpurea is often restrict
the edges of bogs (McDaniel 1971).
urther complicating the assessment of ecological and evolutionary interrelationships among t
arracenia species is the presence of hybrids at many sites (Figs. 2 and 3). Almost all the
ossible natural hybrids have been found, and occasionally large hybrid swarms are encounter
Bell 1952; Bell and Case 1956; McDaniel 1971). All possible hybrids have been produced in
eenhouse, where they seem to be as vigorous and fertile as the parental types (Schnell and
rider 1976).
he possibility of introgression — the exchange of alleles between two distinct species — has be
ised, but there is little evidence that significant genetic exchange is taking place among specaring the same habitat. The isolating mechanisms which prevent or reduce genetic exchange
mong the species have not been intensively studied. It appears that ecological differences in t
tes preferred by various species are not alone sufficient to prevent hybridization. As many as
ve species may inhabit the same bog, and although the ranges of flowering times differ, the
ecies flower simultaneously in some years (McDaniel 1971). Moreover, in the absence of
urning — i.e., when competition is more severe — most species flower later. This may result in
verlap in flowering times on burned and unburned sites adjacent to each other.
ollination of Sarracenuia has been described by MacFarlane (1908) and Jones (1908) and
ommented on by Schnell (1978). Bumblebees, the main pollinators, are polytropic, visiting
any plant species. However, during the peak of the Sarracenia flowering season the bees are
fectively monotropic, at least at sites where there are large stands of flowers, visiting only
arracenia. It may be significant that Sarracenia species which tend to flower simultaneously
ffer in the color, height (length of peduncle), or size of their flowers. For instance, both S . fla
nd S . purpurea flower early, but S. flava has yellow flowers, whereas those of S . purpurea ar
nkish- purple and have somewhat shorter peduncles. S. rubra and S . leucophylla flower
multaneously, and their flowers are essentially the same color. However, S. rubra has small
owers on short peduncles, whereas S. leucophylla possesses larger flowers on much longeredun cles. S . flava and S . alata have flowers of similar color, height, and size, but S. flava
owers earlier and there is only a small area in which the two species occur together.
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hese differences may be the result of reinforcement — i.e., selection against hybrids — but
dditional work is necessary to confirm this. In any event, the differences are not completely
fective in preventing pollen transfer from one species to another. Levin (1978) stated that
sturbance which reduces the size of patches makes hybridization more likely. Presumably,
duced rewards from one species in a disturbed bog may make it necessary for the pollinator
sit several species.
ll species of Sarracenia have a diploid chromosome number of 26 (Bell 1952), precluding
productive isolation resulting from chromosome number differences. If natural hybrids are artile as those produced in greenhouses, the only postzygotic isolating mechanisms that could
nctioning in nature are hybrid inviability (hybrids unsuccessful because of abnormalities or a
ability to compete), hybrid floral isolation (hybrid flowers not attractive to or accessible to
ollinators), or hybrid breakdown (hybrid inviability which occurs after several generations).
ybrid viability may be positively correlated with soil disturbance. McDaniel (1971) noted tha
ch disturbance seems to increase the frequency of hybridization in Sarracenia. This content
supported by the fact that few or no hybrids are present in the few undisturbed bogs that
main. I have previously (1977) remarked on a hybrid swarm that was apparently the result o
ghway construction. Furthermore, in bogs in southern Alabama and Mississippi where my
aduate students and I have worked since the mid-1970s, hybrids are now present at points
here our activities disturbed the soil. The hybrids are typically found near a plant of one of th
arental species. It appears that soil disturbance allows hybrid seeds to germinate and hybrid
ants to survive, whether because such disturbance eliminates competition, creates an area of
fferent soil texture, or modifies other factors is unknown.
nature, plants of certain hybrid combinations are clearly less viable than parental types.
onsider, for example, the hybrid of S. purpurea and S . alata (Fig. 3). The pitchers of S.
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urpurea are short, jug-shaped, partially reclining, possess an erect hood, and fill readily with
inwater. S. alata pitchers, on the other hand, are tall, spindly, erect, taper gradually to a narr
ase, and possess an ascending hood that restricts the entry of water. The hybrid has an open
ifice and is erect, but is characterized by a weak base. When excessive water enters during
eavy rains the pitcher topples, draining its contents and often remaining prostrate. I have foun
at hybrids often possess abnormally large amounts of the plant pigment anthocyanin distribu
unusual patterns. One could speculate that this is indicative of metabolic anomalies that rend
ybrids less physiologically fit than parental types.
ybrids seem to require more water than parental types and are more susceptible to water stre
uring eight years of observations in Santa Rosa County, Florida, I have found that rhizomes
ybrids of S. flava and S . leucopinylla produce fewer leaves than parental types, and in
xceptionally dry years may not produce leaves at all. McDaniel (1971) hypothesized that hyb
nnot compete with parental types and eventually disappear. My observations support this
ontention and indicate that hybrids are also less successful in competing with other plants tha
vade the bog habitat, especially in the absence of fire.
rant (1971) showed that genetically viable hybrids may be at a disadvantage because of poorollination. This factor may reduce backcrossing among the Sarracenia species — that is, cross
f a first generation hybrid with a parent. For instance, the hybrid of S. flava and S . minor flow
a time when neither parental species is in prime flower and when pollinators are probably
oncentrating on other plants. Flower color may also be a factor. Hybrids in which the parents
ave yellow and purple flowers respectively produce flowers of an intermediate color that seem
be less attractive to bumblebees than those of the parental types.
i tcher plant insects
he interior of the pitcher leaves of Sarracenia is a unique microhabitat unparalleled elsewher
ature. Compared to the surrounding environment, the cavity within a pitcher is typically high
relative humidity, lower in light intensity, and somewhat less variable in temperature. In
ddition, pitchers contain a decomposing mass of entrapped prey which is a potential food sou
r other organisms. Although the adaptations that allow pitcher plants to entrap, detain, and
gest prey are highly successful, their presence has presented a counterevolutionary challenge
ganisms that might benefit from an ability to turn the tables on the pitcher plant and colonize
e pitcher environment.number of species have evolved the ability to inhabit the pitchers without being entrapped o
gested. Among these, the most fully studied is a mosquito, Wyeomia smithii, whose immatur
ages occur in the fluid held on the leaves of S. purpurea. Unlike most insects, these larvae ar
either killed nor digested in the pitcher fluid (Goins 1977 diss.; Bradshaw 1980; Moeur and
tock 1980). The larvae of four species of sarcophagid flies of the genus Blaesoxiplnia also
habit Sarnce,uia pitchers, where they feed on entrapped insects (Forsyth and Robertson 197
he larvae of three other flies — Metriocnemus knahi (Chironomidae) (Paterson 1971; Camero
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. 1977); Dolurnipluora cornuta (Phoridae) (Jones 1918); and Bradysia macfarlanei (Sciarida
ones 1920) — are still other occupants of the pitchers.
ll three species of the noctuid moth genus Exyra occur in Sarracema pitchers (Fig. 4), where
eir larvae feed on the leaf tissue (Jones 1921; Judd 1957; Brower and Brower 1970; Rymal
980 diss.). Two other moths, Papaipenna appasionata (Noctuidae) and Endothenia daeckean
Tortricidae), feed exclusively on pitcher plant tissues but do not enter the pitchers themselves
y contrast, the aphid, Macrosiphum jeanae, completes its entire life cycle within the pitchers
Robinson 1972).
Two anoetid mites, Anoetus gibsom and A. hughesi, are known only from Sarracenía pitchers
Nesbitt 1954; Hunter and Hunter 1964), as is the predaceous phyto seiid mite, Macroseius
scutatas (Chant et al. 1959). At least fourteen of these arthropods are obligate associates of
arious Sarracenia species. The mechanisms by which these species escape entrapment and
gestion merit more intensive study.
atur al habitat maintenance
he heliophytes of the bog habitat are dependent on natural phenomena that continually retard
ocesses of succession which would eventually eliminate them. First, soil acidity coupled wit
w levels of nutrients, at least at some sites, inhibits the invasion of competing species. Secon
naerobic soil conditions resulting from frequent saturation create an environment inhospitable
oisture-intolerant types. Third, periodic fires repeatedly eliminate fire-intolerant types. Most
e bog species have underground rhizomes or rootstocks and hence are not harmed by fire.
re is undoubtedly the most important of these
ctors. This is demonstrated by the fact that regardless of the moisture regime and soil
onditions, the absence of fire inevitably results in eventual elimination of the bog species. Th
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aramount role of fire in maintaining these habitats has been documented by a number of wor
Wells and Shunk 1928; Eleutarius and Jones 1969). The bogs therefore represent a fire
bclimax or disclimax, and they depend on fire not only to eliminate competitors but to releas
any nutrients bound up in organic matter as a result of previous growth (Eleutarius and Jones
969). It should be pointed out that nitrogen is largely volatilized by burning and does not
pically increase in soils after fire.
he season during which fire occurs may influence the floristic composition of the bogs. In the
ast, fires apparently occurred most frequently in the summer as a result of lightning (Komare
965). At present, most fires are caused by man and occur during the winter. Data on the effec
f this shift are lacking; however, winter fires would seem less effective in opening space for t
ermination of seeds of the bog species.
enfound (1952) and others have conjectured that pitcher plant habitats are at times created by
e cutting of longleaf pine stands. In some cases, reduced evapotranspiration following cuttin
ay increase soil moisture to the extent that the site becomes suitable for bog species. Howeve
e creation of drainage ditches and other preparations for replanting produce conditions whic
event bog communities from developing in most logged sites. The idea that bogs are “formeainly through cutting of the low pine forests” (Penfound 1952, p. 431) is untenable, consider
e vast expanses they occupied before significant disturbance by man. It is possible that
estruction of forests by hurricanes may have played a part in maintaining coastal bogs.
efore man’s activities began to affect the pitcher plant bogs, these communities were abunda
nd conspicuous on the Lower Gulf Coastal Plain. Based on extensive on-site surveys to
etermine habitat suitability and detailed examination of county soil maps, I have calculated th
pre-Columbian times these communities occupied approximately 2,935 km2, or about 6% o
e colored area in Figure 5. Nearer the coast the bogs were probably larger and more
onspicuous. From the writings of Bartram (1791) and Harper (1918) it seems probable that ar
ear the coast from Pensacola, Florida, west to Pascagoula, Mississippi, were nearly continuou
ogs until the late 1800s, with some bogs covering thousands of acres.
he area occupied at present is significantly smaller. Bogs in a natural or nearly natural condit
e now very rare, with perhaps less than 12 km2 remaining. Altered sites which retain the asp
f bogs and contain many of the component species occur on an additional 60 km2. Even thes
beral estimates mean that at least
7% of the former bogs have been destroyed or seriously altered. The reasons for the
sappearance of these communities are myriad, and I have summarized many of them previou977). The most damaging factors have been draining of land and restriction of fire.
he frequency of fires in pitcher plant bogs is much lower now than in pre-Columbian times a
as greatly decreased in the past few decades. Not only are there intensive efforts to prevent an
ontrol fires, but roads, railroads, tilled cropland, pastures, and fire lanes serve as barriers to
strict tile spread of fire. A decline in the frequency of fire can be damaging not only because
utrients remain inaccessible but because of tile extreme heat generated by the eventual
ombustion of large amounts of accumulated vegetation, since such heat can affect perennial
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nderground plant parts.
the absence of fire the bogs are invaded by a variety of species, including Myrica certifera,
ex glabra, Hypericum fasciculatum, Magnolia virginiana, Nyssa sylvatica, Pinius elliotii,
milax laurifolia, and a host of ferns, grasses, sedges, and broadleaf herbs. Following invasion
oody forms, increased transpiration lowers the water level in the bog soils. This reduction in
il moisture allows further invasions by less moisture-tolerant species. Over a period of twen
ears this process can result in the elimination of the typical bog ecosystem.
rainage is most often associated with attempts to convert bog sites to cropland, pasture, or
tensive pine monoculture. As nearly as 1 can determine, the latter is currently responsible fo
e destruction of more bogs than all other factors combined. Drainage is also a byproduct of
ad construction and stream channelization programs and may result from canalization in coa
eas. Destruction of bogs by drainage does not necessarily entail major physical alteration. A
tch as shallow as 2 dm will usually result in the drying of the surface soil to an extent that wi
ventually eliminate tile bog species. Many of the bogs that today appear healthy contain ditch
at spell their ultimate demise.
host of minor factors also play a part in decreasing bog acreage. Because of their contour anainage, bogs are often chosen as sites for farm ponds. I have examined over fifty such sites.
cross the Lower Gulf Coastal Plain farm ponds have probably replaced nearly a thousand acr
f bog habitat. Urbanization, highway construction, coastal development, and herbicide
pplication are also altering bog sites. Overcollecting by both professional botanists and plant
nciers has been responsible for tile elimination of certain species at some sites, with pitcher
ants and orchids usually hardest hit.
razing causes major changes in tile composition of the bog flora (Pullen and Plummer 1964)
lthough cattle do not feed on pitcher plants, their trampling destroys them (Plummer 1963;
olkerts 1977), and continued intensive grazing results in a rapid decrease in species diversity
nd eventual destruction of the bog.
he future of the bogs
early all the processes that are altering and destroying pitcher plant communities are
celerating. If present trends continue, there is little hope that any significant amount of this
abitat will survive into the twenty-first century. Yet despite this fact, and despite the clear
ientific and aesthetic value of this startlingly unique assemblage of organisms, virtually nofort has been made to preserve some of these communities.
lthough some sites do exist on public lands — notably in the Apalachicola, Conecuh, and
esoto National Forests and on Eglin Air Force Base — in most cases little concerted effort ha
et been made in these areas to ensure bog preservation. In fact, some practices quite detrimen
pitcher plant ecosystems are still being carried out at all these sites.
n all sites, hog preservation will require some management, especially to ensure that burning
ccurs periodically. Some modifications may also be necessary to maintain the proper moistur
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gime if changes in nearby areas threaten to disturb the hydrologic characteristics of the bog.
hese requirements could perhaps be met in a national park or preserve consisting of some
0,000 acres distributed in four or five blocks across the Southeast. Similar national parks hav
ng ago been established to preserve other unique ecosystems such as the Everglades or the c
rests of the Great Smoky Mountains, or to protect other precious species such as the sequoia
nd the saguaros.
any important questions about the evolution and ecology of pitcher plant communities and
bout the biology of carnivorous species remain to be answered. Yet we cannot wait for more
etailed scientific information to justify preservation, for if we do, the communities will be go
efore they can be preserved. The disappearance of the pitcher plant bogs would be a biologic
tastrophe of great magnitude, closing the door forever on further study and enjoyment of an
replaceable member of earth’s varied ecosystems.
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