|
Contents
Forum -- Letting Go of Certain
Myths
You could say it started with the Spaniards.
Back in 1540, the Spanish explorer Francisco Vasquez de Coronado introduced
domestic livestock on the U.S. range500 head of cattle, 5,000 sheep, and
1,000 horses. The pace picked up when Spanish missionaries spreading across the
Southwest brought an estimated 50,000 sheep and 20,000 cattle north from
Mexico.
Obviously, the concept of livestock grazing the range is not a new
oneand neither is the concept of concern about the environmental impact
of livestock on the range. More than 60 years ago, Congress passed the Taylor
Grazing Act of 1934, aimed at stopping "injury to public grazing lands by
preventing overgrazing and soil deterioration, to provide for their orderly
use, improvement and development, to stabilize the livestock industry dependent
upon the public range, and for other purposes."
The United States today has about 770 million acres of rangeland, of which
more than half are privately owned, with 43 percent federally owned. To put
that total in perspective, today's rangeland acreage is about 272 million acres
less than available rangeland at the time Europeans began settling what is now
the United States.
In other words, we still have about 74 percent of the rangelands of those
early days. The "missing" 272 million acres have been converted into
our farms, forests, urban areas, industrial sites, highways, and reservoirs.
How should we take care of these remaining 770 million acres? By using a
variety of management tools to work within the rangeland ecosystem. One of
these toolsa very valuable oneis grazing.
Livestock grazing can help promote vegetation that's good for watersheds and
wildlife. That's because different classes of animals graze different types of
plants. Cattle and elk eat mostly grass, deer primarily browse woody plants and
eat forbsbroadleaf herbswhile sheep and goats have a mixture of
plants in their diet.
Producers can put different types of animals on range at different times of
the year to alter the array of vegetation present by virtue of what those
animals will eat and what they'll leave behind. Producers can also use some
livestock to control noxious weeds or to thin or clear brush.
A good place to see this highly diversified vegetation use in nature is
Africa's Serengeti Plain. A wide variety of wild and domestic ruminants live in
that area, each group following another over the plain, each with a certain
niche diet of specific vegetation. The various parts of the
ecosystemincluding the animals and plantshave worked together over
centuries to achieve a relative balance.
During the past decade, research has enhanced our knowledge of how these
natural systems work and how to manage within them to reach specific
goalswhether those goals are greater meat production, more wildlife, or
even wildfire control by grazing blaze-prone areas such as California's
chaparral slopes.
We know much more today than we did 60 years ago, when the Taylor Grazing
Act was passed. But there's still a lot to learn. By focusing more on the
interrelationship between soil, plants, and animals, we can gain a better
understanding of how productivity and diversity of our rangelands can be
enhanced through careful management.
On some rangeland, climatic changes, soil erosion, natural disasters, and
other factors have altered the diverse mixture of plant and animal life, and
renewal of those communities is not possible for the foreseeable future. But we
attempt to find ways to manage and protect the remaining rangeland to prevent
further degradation.
We must be flexible enough to think in terms of using new, as well as
different, management tools on rangelandto see that there's a place for
sheep and cattle and goats and deer, as well as humans.
We must also learn to let go of certain myths: that grazing is automatically
bad for rangeland, for example, or that livestock will always destroy
streambanks and riparian areas when those areas are grazed.
In this issue of Agricultural Research magazine, you'll read how ARS
scientists at Dubois, Idaho, are simulating commercial sheep operations in
order to study the actual impact of grazing on summer range in the Centennial
Mountains of Montana and Idaho.
They've found that when sheep arc managed wisely at a moderate stocking
rate, there's plenty of vegetation left after the sheep move on, and they do
not cause massive soil erosion in riparian areasone myth dismissed.
Large ruminants have always been part of our rangeland, though in
pre-settler days they may have been bison, elk, or moose. Our research is aimed
at finding ways to continue using the rangeland for many purposes, including
harvesting vegetation and turning it into food and fiber, while ensuring that
the actions we take today don't imperil natural rangeland resources for
tomorrow's generations.
R. Dennis Child
ARS National Program Leader Range and Global Climate
[Top]
|