What is a bit surprising about
this type of work is that we are only doing this now. It is an obvious question that deserves an
answer. Of course, in the past, perhaps
herds were smaller and shifts of large herds to different grazing grounds were
both common and necessary depending on the season.
Allowing pasture to properly
restore itself is surely good husbandry and this merely confirms it. Grass constantly cropped at several inches
will not be regenerating a healthy root system and this slowly degrades over
time. After all, just how deep does a
lawn’s root system go? Yet those grasses
are quite capable of going much deeper.
It surely applies in a pasture
and it is better to allow an optimal growth before grazing starts. I suspect that traditional farming on small acreages
did exactly that as best as they were able.
Multi-paddock grazing is superior to continuous grazing
by Staff Writers
The continuously grazed ranches in each county were stocked at
approximately the same stocking rates from year to year over at least the
previous nine years. They were otherwise selected by the Natural Resource
Conservation Service technical staff in each county as being representative of
traditional continuous-grazing ranches in the region.
A long-term study verifies multi-paddock grazing improves vegetation,
soil health and animal production relative to continuous grazing in large-scale
ranches, according to Texas
AgriLife Research scientists.
The study measured the impacts on vegetation and soils achieved by commercial
ranchers who adapted management practices in response to changing circumstances
to achieve desirable outcomes, said Dr. Richard Teague, AgriLife Research
rangeland ecology and management scientist in Vernon.
At the ranch scale, when multi-paddock grazing is managed to give best
vegetation and animal performance, it is superior to continuous grazing in
relation to conservation and restoration of resources, provision of ecosystem
goods and services, and ranch profitability, he said.
Teague said this study differed from those conducted by researchers who
investigated multi-paddock grazing in relatively small experimental areas,
without managing adaptively the way a successful, conservation-oriented
commercial rancher would.
In rangeland ecosystems, maintaining normal soil and ecosystem function
over the landscape and watershed is possible only if there is adequate plant
cover and species composition to provide protection from soil loss, he said.
This allows microorganisms to prosper and maintain ecosystem functions such as
water-holding capacity, control of erosion, soil fertility and
forage production, he said.
"In our study we examined the accumulated impacts of nine years of
different grazing management categories on vegetation and soil parameters at a
commercial-ranch scale," he said.
The study evaluated the impact of multi-paddock grazing at a high
stocking rate compared to light continuous and heavy continuous grazing on
neighboring commercial ranches in three proximate counties in North
Texas tall grass prairie. The same management had been conducted
on all ranches for at least the previous nine years.
Multi-paddock grazing was managed using light to moderate defoliation
during the growing season followed by adequate time to recover, Teague said.
With multi-paddock grazing and ungrazed areas, the vegetation was
dominated by taller more productive grasses. With heavy continuous grazing, it
was dominated by less productive short grasses and forbs, he said. Light
continuous grazing had a lower proportion of tall grass species than
multi-paddock grazing or ungrazed areas.
Teague said there was more bare ground on heavy continuous than light
continuous, multi-paddock and ungrazed areas, while soil aggregate stability
was higher with multi-paddock than heavy continuous grazing, but not light
continuous grazing and ungrazed areas.
Soil compaction was lowest with multi-paddock grazing and ungrazed
areas and highest with heavy continuous grazing, he said.
Water infiltration rate did not differ between grazing management
categories, but soil erosion was
higher with heavy continuous grazing as compared to other grazing management
categories, Teague said. Soil organic matter, water holding and fertility were
higher with multi-paddock grazing and ungrazed areas than both light continuous
and heavy continuous grazing.
The fungal/bacterial ratio was highest with multi-paddock grazing as a
result of the greater amounts of tall grass species, he said, indicating
superior water-holding capacity and nutrient availability and retention for
multi-paddock grazing.
"This study documents the positive results for long-term
maintenance of resources and economic viability by ranchers who use adaptive
management and multi-paddock grazing relative to those who practice continuous
season-long stocking," he said.
The general management on the ranches using multiple paddocks per herd
was to graze a pasture lightly to moderately for one or three days, followed by
a recovery period of approximately 30-50 days and 60-90 days during fast and
slow growing conditions, respectively.
This resulted in two light-to-moderate defoliations during the growing
season with regrazing before the majority of plants switched from vegetative to
reproductive phases, Teague said. This kept the plants in a leafy, vegetative
condition during the growing season to provide a high level of forage quality
for the livestock and to ensure the best possible forage regrowth after
defoliation.
During drought periods, animal numbers were adjusted to match forage
amounts. In the winter, the goal was to graze and trample most of the standing
forage to enhance litter cover and minimize self-shading that would limit plant
growth in the following spring, he said.
The continuously grazed ranches in each county were stocked at
approximately the same stocking rates from
year to year over at least the previous nine years. They were otherwise
selected by the Natural Resource Conservation Service technical staff in each
county as being representative of traditional continuous-grazing ranches in the
region.
"The results we measured, representing the combined positive
effects of multi-paddock management, indicate the multiple advantages of this
management option," Teague said. "Multi-paddock grazing resulted in a
higher proportion of desirable tall grasses, a lower proportion of less
desirable short grasses, annual winter-growing grasses and forbs, and higher
standing crop, even with a higher stocking rate than the lightly stocked
continuous grazing."
Although the stocking rate was less with lightly stocked continuous
grazing, the preferred plants and areas were never allowed any recovery under
continuous grazing while multi-paddock grazing, correctly managed, prevented
overgrazing and allowed for adequate recovery after defoliation, he said.
By ensuring light-to-moderate use in the growing season with adequate
recovery, the preferred forages are able to capitalize on good growing conditions,
Teague said.
"The use of multiple paddocks per herd on commercial ranches
spreads grazing over the entire landscape in the numerous smaller paddocks,
rather than allowing a concentration of grazing pressure on preferred areas in
the landscape," Teague said.
"It also provides the manager with the option of regulating the
grazing pressure on preferred areas and plants by adjusting when to move
animals to a new paddock, and provides the means to allow grazed plants to
recover before they are grazed again.
"If managers adaptively respond to the ever-changing climate by
changing the periods of grazing and time allocated for plant recovery, and
adjust livestock numbers to match the available feed, as the multi-paddock
grazers in this study did, negative effects of grazing by the livestock can be
minimized."
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