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With
careful management, grazing can help restore the Western range
By
Allan Savory
for Headwaters News
The
grasslands of the Rocky Mountain West serve as enormous catchment
areas for some of America’s most important rivers. Though they
are losing tons of soil to erosion and shedding water to the extent
that flooding has increased, these grasslands could be made healthy,
and at little or no cost.
Grassland soils, so vital to the nation and our cities and agriculture,
can only retain water and resist erosion if covered with living plants
or litter formed from plant remains. But in the Rocky Mountain West,
millions of acres are characterized by the sparseness of the grass,
plants, and more dramatically, by the lack of plant litter between
the living plants.
Thus, when you measure it, as I have, you find that even on the best
managed rangelands, 50 to 95 percent of the soil surface between plants
is actually bare and exposed, or at best covered with algae and lichen
crusts.
This amount of soil exposure inevitably leads to high runoff (flooding)
and high soil surface water evaporation (drought).
The types of plants are also important. The grasslands of the Rocky
Mountain West are dominated today by woody plants, such as sagebrush,
annual grasses that do little to stabilize soil, and a few rest-tolerant
perennial grass species of low productivity.
It is unnatural to have so few plant species dominate large areas
of vastly different soil types, but it is occurring on private, public
and tribal lands and in wilderness areas and national parks.
Why is so much land deteriorating?
For simplicity’s sake, we can say there are three broad types
of plant in the Rocky Mountain West: evergreen and deciduous woody
plants (trees, shrubs, weeds), and grasses.
Of these, other than in higher rainfall environments where a full
canopy of trees can grow, soil cover is derived primarily from living
grass plants and their dead litter. All plants and plant parts follow
a simple life cycle of birth, growth, death and decay.
Biological decay depends upon billions of microorganisms. If something
should block decay, plant parts oxidize and turn gray, leading to
the death of most perennial grass species and high fire risks.
Evergreen trees have leaves that remain green throughout the year.
Deciduous trees have green leaves that grow profusely in spring
and summer. In fall these trees withdraw food from their leaves,
which change color, and are then cut off and shed.
If the tree could not shed its own leaves, the dead leaves would
not decay (too few microorganisms above soil surface level) but
would oxidize and smother the tree’s buds the following spring.
All perennial grasses grow green stems and leaves in the growing
season. In the Rocky Mountain West where moisture is low and there
is a long dormant season, the grasses move nutrients out of their
leaves and into their roots and bases well before winter. Their
dead leaves and stems turn yellow. But where deciduous trees can
shed leaves, no grass in the world developed this ability.
The role of animals in the plant life cycle
Grasses do not have any mechanism to shed their own stems and leaves
simply because they co-evolved with millions of grazing animals.
These animals removed dead leaf and stem, ensuring that the growth
points, or buds, were exposed to sunlight in the spring. That is
why most perennial grasses have their growth points at ground level,
below grazing height. The grasses were as dependent on the grazers
as the grazers were on them.
The animals, unable to digest grass, had a long-established partnership
with microorganisms in their gut, which enabled them to break down
a mass of forage into smaller bulk (dung and urine), which could
more easily decay.
What the animals did not graze they generally trampled to the ground
as litter, where it would eventually decay. Without the grazing
animals to perform this vital function, the decay part of the perennial
grass’s life cycle is disrupted.
The dead leaves can take decades to break down, by oxidizing and
weathering, exposing the plant to an early death by the choking
gray leaves.
So fire — the most severe form of oxidation — is often
used to clear the highly flammable material away. When the plant
dies, or is kept alive by fire, soil is exposed.
Obviously some perennial grasses developed in sites seldom if ever
reached by large grazing animals, and they can survive years without
leaf removal.
They do this by forming branches like a tree with growth points
high up on the plant (tobosa), or developing a very sparse structure
(gramma or Aristida). These are the types of grasses that now dominate
the Rocky Mountain West.
The decline of the grasslands
Over billions of years, despite periodic (in geological terms) major
disruptions, the soils and biological communities in the Rocky Mountain
West functioned with this mutual dependence.
Then suddenly there appeared on the North American landscape some
10,000 to 15,000 years ago, a new creature, the first human predator.
(more)
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Cattle
on the run
By
Greg Lakes, editor
Headwaters News
March 13, 2002
Allan
Savory's theories have been debated for decades and they're still
far from universally accepted. Witness competing columns a month
apart in High Country News:
intensive is better, or the best
grazing is no grazing.
But perhaps the future lies in one of Savory's last paragraphs:
The
U.S. Forest Service is currently collaborating with the Savory
Center to see if we can establish a national learning site in
Idaho where we can encourage environmental organizations, as well
as livestock operators, to work together to reverse the land degradation
that is of such concern to all of us.
In the meantime, it would seem that open animosity
isn't going away anytime soon.
The pendulum may be swinging back from the Clinton-era emphasis
on conservation, with the sacking
of Idaho's BLM director, reportedly at the hand of Idaho Sen.
Larry Craig and ostensibly because she angered ranchers and motorized
recreationists.
Score one for ranchers.
Environmentalists have started to outbid
ranchers for grazing rights on state lands in Utah, Idaho, New
Mexico and Arizona, a practice most recently upheld by the Arizona
Supreme Court last November.
The tactic has removed cattle from about 100,000 acres of Western
range, a minuscule fraction of the 30 million or so acres open to
grazing, but environmentalists have claimed public relations victories,
arguing that the court decisions have highlighted the subsidized
nature of grazing on all public lands.
On the flip side, leery ranchers in southern Utah and northern Arizona
have promised to sue if environmentalists or federal managers reduce
grazing allotments in the Grand Staircase-Esalante National Monument.
Still ranchers are getting squeezed, even if at times it's voluntarily.
Wyoming ranchers agreed to move their sheep and cattle off key grizzly
and bighorn range in a landmark agreement that both sides hailed
as a hallmark in consensus.
But New Mexico ranchers are protesting area tribes' proposal to
raise bison on national grassland allotments that previously had
belonged to cattlemen.
In the adamantly non-voluntary category, activist Jon Marvel's Western
Watershed Project has appealed
BLM leases on 250,000 acres in northwest Colorado, it's first
attack in Colorado in its avowed campaign to end grazing on public
land.
The appeals said grazing not only destroys plant communities, but
ranchers kill predators and their livestock destroys fish habitat.
Ranchers countered that so much of Colorado is public land that
the industry can't survive without federal grazing rights.
One of the most indisputable impacts of grazing on native species
is the decline
of the West's sage grouse. Denuded habitat means less food and
scant protection for the birds or their eggs.
And while the sage grouse looms as the spotted owl of the interior
West, it represents a spectrum of other disappearing plant and animal
species that used to be common in the sagebrush ecosystem.
Not everyone is engulfed in conflict; in addition to Savory, some
see common interests.
The BLM's plan for Moffat County, Colo., opposed by Marvel and company,
may be doomed
as written, but it has the framework for a precedent-setting
approach to management -- oversight by a local trust -- and an alternative
to chronic antagonism.
And farther south, the Santa Fe-based Quivera Foundation has about
850 members, about evenly divided among ranchers, environmentalists
and government staffers. They endorse what they call the New Ranch
and a holistic approach that includes intensive grazing -- but only
sometimes, in some places.
And just to depart with an even more disturbing thought, some of
Quivera's member scientists say global
warming has wrought more changes upon the Western range in the
past 25 years than grazing or the lack of it, and those effects
will only accelerate.
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