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Pitcher Plant Bogs are
Among the Most Unique Communities of the Longleaf Pine Ecosystem
(bolded words in text indicate key words
and concepts)
Student
Information:
Pitcher plants are carnivorous plants. Carnivorous
means that the plants feed on insects they trap in their tube-shaped
leaves. Once insects get in these tubes, they are trapped and can't
get out. These plants are found in places where water is close to
the surface and the soil has few nutrients. These plants also need
lots of sunshine. Fire is helpful because it kills and removes other
plants that might shade the pitcher plants out. Many other interesting
plants and animals live in and around these areas.
Teacher Information:
Imbedded within the longleaf pine ecosystem are countless varieties
of microhabitats. Among the
more unique of these habitats
are pitcher plant bogs. Pitcher plants and their companion plants
are specialized to exist in
a narrow set of conditions. Soil moisture is critical and many "bog"
communities are actually the result of a hard, impermeable clay
layer beneath porous sand. Rainwater percolates through the sand
but runs into an impermeable clay "lens" where it is either
trapped (like a pool) or seeps out the side of a hill. These nutrient-poor,
moist sites are ideal for the carnivorous pitcher plants. Bogs common
to many "flatwood" longleaf areas are called "wet
prairies" while other bogs found on hillsides are
called "seepage slopes".
The transition from forest to an open bog is not immediate. Forests
usually grade into a wetland, bog habitat. This transition area
is called an ecotone and hosts
a rich variety of plant and animal species.
There are several types of pitcher plants
in longleaf forests, as well as other carnivorous plants, e.g.,
hooded pitcher plant, trumpet pitcher plant, white-topped pitcher
plant, and parrot pitcher plant. Pitcher plants have modified leaves
shaped into hollow tubes (that look like a water pitcher), which
attract insects. Downward pointing hairs and slippery walls make
escape difficult and the hapless insects are dissolved and digested
by enzymes in the bottom of the pitcher. The tiny sundew and dewthread
can trap small insects on flat sticky leaves before slowly digesting
them. Other bog plants include colic-root; goldcrest; meadow-beauty
(also called deerflower); white-topped sedge; orange milkwort (also
called bog "Cheetos" because of their resemblance to that
treat); bog-buttons (also called "hatpins"); several species
of orchids; and many other wildflowers. Both soil moisture conditions
and full sun are critical to these plant and animal communities.
Most of these bog plants have little shade
tolerance. Pitcher plant bogs are fire
dependent habitats. The frequent fires common to the
longleaf ecosystem keep woody shrubs from encroaching on bogs. Without
fire, moisture-loving shrubs invade; drying up bogs and shading
out the herbaceous plants. Today, many of these unique bog systems
are exceptionally rare; having been lost to either development,
water drained out of them, or fire not being allowed to move through
them.
The Spanish moss seen hanging from the trees is an example of commensalism-a
one-way relationship. Spanish moss is considered an epiphyte-meaning
it requires the host (pine tree in this case) for mechanical support
rather than a source of nutrients or water. The pine tree is neither
benefited nor harmed by the presence of the Spanish moss. The moss
plays host to numerous varieties of invertebrates both hanging from
the tree and when it falls from a limb onto the ground.
Key Words and Concepts (click
on for glossary definition): carnivorous
plants, commensalism,
ecotone,
epiphyte,
fire
dependent, habitat,
microhabitat,
pitcher
plant, seepage
slope, shade
tolerance, specialization,
wet
prairie.
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