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Grazing
and the Landscape -
Introduction
Grazing and
the Northern Plains Landscape Northern Plains ecosystems were shaped
over thousands of years through the influence of large herbivores,
especially bison. Eyewitness accounts of early European travellers
highlighted both broad and local impacts to the very limits of the
bison’s range. In general, impacts included heavy defoliation,
trampling, wallowing, rubbing of trees, and fouling water with feces
and urine.
However, in
that open pre-settlement environment with multiple choices for grazing,
there is little to suggest that bison herds lingered, season long,
on riparian areas. The overall bison migration probably followed
a seasonal pattern between summer ranges in the mixed grass prairie
and wintering periods in the foothills and parkland where shelter
and abundant forage could be found. Resident bands of bison may
have occupied certain local areas year- round but the prevailing
view is that the big herds tended to follow this seasonal pattern.
The grazing
strategy of bison was likely dispersal throughout a variety of landscape
types, unlike domestic livestock (particularly cattle), which have
an affinity for water. The natural system can be characterized as
a grazing regime timed and controlled by season and climatic fluctuations,
including periodic drought and fire, where periods of grazing were
followed by variable rest periods. What the pre- settlement, natural
system teaches is that after there was grazing there was rest, and
prairie riparian communities evolved under such a regime for millenia.
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