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Views of the Tallgrass
Prairie
The Complex Prairie Ecosystem
Prairies historically
covered 400 million acres of North America. This sea of grass stretched
from the Rocky Mountains to east of the Mississippi River and from
Saskatchewan, south to Texas. It was the continent's largest continuous
ecosystem supporting an enormous quantity of plants and animals.
Prairies began appearing in the mid-continent from 8,000 to 10,000
years ago and have developed into one of the most complicated and
diverse ecosystems in the world, surpassed only by the rainforest
of Brazil.
Prairies exist in areas too wet for desert yet
too dry to support healthy forests. Prairies respond to their
environment, which includes soil type, water availability, and
natural forces such as grazing and fire. These have resulted
in three distinct prairie regions. In the West, in the dry Rocky
Mountain rain shadow, there is the ankle high short-grass prairie
with its buffalo grass and blue grama. The eastern prairies
are wetter and support tallgrass prairies with Big Bluestem,
Indian Grass, and Switch Grass growing to heights of eight feet
at times. Between lies the mid-grass prairie dominated by side-oats
grama and wheatgrass, with a mixture of shortgrass prairies
in dry sites and tallgrass in wetter sites. The prairie is well
known for its fauna. Some authors have estimated that there
were between 30-60 million bison roaming the prairies. Elk,
deer, and antelope also grazed in astounding numbers. Large
predators preying on the grazers included the grizzly bear and
wolf. Hoards of smaller wildlife from birds to pocket gophers
were inhabitants adapted to this unique ecosystem. |

Man discovered the rich soils that exist in the prairies about
150 years ago. Finding the prairie soils outstanding for crop
production, they plowed the prairie everywhere they could for
the production of wheat, corn, and other domestic crops. Today,
the most fertile and well-watered region, the tallgrass prairie,
has been reduced to but 1% of its original area. This makes
it one of the rarest and most endangered ecosystems in the world.
The largest remaining area still left unplowed is in the rocky
and hilly region of Kansas called the Flint Hills. This physiographic
region averages 60 miles wide and stretches from the Nebraska
border, south into northern Oklahoma. |
 Tallgrass
prairies are an extremely complicated web of life. At first
sight, one sees a landscape dominated by grasses. Eighty percent
of the foliage is indeed made up of grasses, from 40 to 60
different species. The other 20% of the primary vegetation
is made up of over 300 species of forbs or flowers.
The prairie also has over 100 species of lichens and liverworts
as well  as
numerous species of woody trees and shrubs along creeks and
protected areas. Prairie landscapes vary in soil types and
depth, moisture, and slope. This creates many different situations
and niches for specific plant communities to fit into. For
example, in the wet seeps, sedges and prairie cord grass thrive
but bluestem and buffalo grass would drown. In the bottomland
prairie areas, different grasses and flowers grow. Species
that require more moisture and deeper soils thrive in the
bottomland. On the other hand on the dry, shallow, wind-blown
hilltops, the drought hardy hairy grama thrives.
Plants have evolved on a landscape that can be difficult to
survive on. Climates on the prairie range from extreme heat
and drought in August to bitter cold winters locked in ice
and frigid winds.
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Fires sweep across the prairie consuming everything
in its path. On top of this there is a barrage of organisms feeding
on these plants as fast as they grow. The secret to the survival
of the prairie plants in such a hostile environment is that 75-80%
of the prairies biomass, or plant material, is underground. The
visible plants seen on the landscape are merely the photosynthetic
leaves gathering sunlight for a much larger community underground.
Just beneath the surface lies the main stems or rhizomes, running
horizontally. Here they lie protected from drying, grazing, trampling,
fire, and frost. Tough fibrous roots descend from these rhizomes
deep into the ground. Roots of some plants such as dotted gayfeather
have been reported to go 10 to 15 feet deep. On these roots, are
microscopic "rootlets" numbering in the billions and utilized
by the plant. Even smaller than rootlets are mycorrhizae that support
plant growth by drawing in nutrients too little for even rootlets
to obtain. The roots of plants are so numerous, that were one plant's
roots placed end to end they would stretch for miles. The competition
for nutrients and resources is fierce, so thickly interwoven are
plant roots that early settlers were able to cut bricks out of the
sod to build homes and schools.
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