Abstract
NCAT |
Well-managed forage systems contribute significantly to the sustainability of a farm/ranch operation. This publication addresses numerous aspects of sustainable pasture integration, grazing rotation strategies, and management options. It covers: grazing systems, pasture fertility, changes in the plant community through grazing, weed control, and pasture maintenance. It also discusses planning and goal-setting,
and offers an appendix item on trees in pasture settings.
Table of Contents
This publication contains references to enclosures that are available in hard copy only. Please call our toll-free number to receive a copy.
1-800-346-9140 |
Introduction
Management is the key to healthy, productive
pastures. Controlled, rotational,
or management-intensive
grazing has increased forage production for
many producers. Skillfully using livestock to
harvest forages leads to improved soil fertility,
a diverse, dense, and useful pasture ecology,
and an extended grazing season. Fertile
soil and productive pastures, in turn, support
healthy animals.
Well-managed forage systems contribute
to an operation’s sustainability in several
important ways:
- Lands most susceptible to erosion
(or otherwise unsuitable for annual
crops) can be maintained as permanent
sod.
- Land used for row crops benefits
from a year or more in pasture as
part of a crop rotation plan. The life cycles of annual weeds and other
crop pests are interrupted during
the pasture years of the rotation.
- Soil health improves as the content
of organic matter increases under
good grazing management.
- Soil structure improves over time
as compaction and hardpan is
reduced.
- Ruminants (cattle, sheep, deer,
goats) thrive in a better balanced
agro-ecosystem and produce milk,
meat, and fiber from grasses that
cannot be digested by humans.
Livestock eat excess plant materials
while animal wastes contribute
nutrients for plant growth.
- Marketing meat, milk, fiber, and
other animal products can diversify
producer income.
In the not-too-distant
past, farmers more fully
integrated crop and
livestock enterprises
as a matter of course.
Grain produced in
field rotation was either
sold or fed to livestock,
depending on market
conditions. Cropland
was rotationally seeded
to forages, usually for
several years. Land not
suitable for crop production
was grazed.
Animals also foraged
after-harvest crop residues
and the remains
of failed crops. These
time-honored strategies
are not totally absent
from today’s agricultural landscape; however,
a better integration of crop and livestock
enterprises is a necessary step toward
the goal of sustainable pasture lands.
The sun is the source of energy for the entire planet
and much of this energy is captured and stored by
plants. Plant fibers that are otherwise unusable by
humans are eaten and converted into a new form
of stored energy by domestic ruminants, such as
cattle, sheep, and goats. Producers can then market
this animal meat, milk, and fiber. In a very real
sense, annual crop and livestock systems constitute
a harvest of the sun and a new source of wealth. And
the most efficient system to convert the sun’s energy
to money is likely to be the most profitable. A dense
and diverse forage community offers an excellent
opportunity for livestock managers who can harvest
and market it. |
Planning and Goal-Setting
In analyzing your pasture systems, think of
yourself as a grass farmer, and the livestock
as a means to market the forage. It doesn’t
matter whether the grass is produced on
permanent pasture, on marginal land,
or on crop land in the pasture years of a
rotation. An excellent goal is to produce
enough good-quality
forage to sustain livestock
over as much of
the year as possible.
Then choose the livestock
that can best
use it.
Of course, different
livestock species and
classes of livestock
have different feed
requirements and
forage preferences.
Most cow-calf operations,
for instance,
have lower forage
nutrition and soil fertility requirements than do most dairies.
Consistent production of high-quality
forage under current management makes a
dairy or stocker enterprise an option to consider.
Otherwise, a different class of cattle,
sheep, or other ruminant (either alone or
in a multispecies system) may be more
suitable to your specific site and management
capability.
ATTRA has developed several sustainability
checksheets for educators and producers to
use in evaluating any operation that includes
a grazing system. Each is designed to make
the producer think about how different parts
of the pasture-based enterprise relate to each
other. The checksheets were developed by
teams of producers and educators and have
been tested in several locations. Checksheets
currently available include:
You can also call ATTRA to request a printed copy of
any of these checksheets. |
In setting production goals for any livestock
enterprise, consider the economic return
per acre rather than production per animal.
This is a change from traditional thinking.
Compare pounds produced per acre or per
dollar invested rather than weaning weights
or shipping weights. This type of analysis
shows actual profitability more clearly. (See
enclosed article by Doug Gunnink for tools
to analyze profitability.)
Renovating Pastures vs.
Establishing New Ones
Planting a new pasture offers the opportunity
to choose forage species and varieties
suited to the livestock type adapted to
the soil and climate. Efficiency is further
enhanced by matching the season of maximum
forage production to the period when
livestock can best use it or most need it.
Further, planting a diverse mixture of forages
with differing maturities provides a
high-quality, longer grazing season.
County or state Extension personnel are
often good sources of information about forage
varieties adapted to an area or even to a
specific site. The Natural Resources Conservation
Service (NRCS) is another good source of
information on forage production practices
appropriate for particular grazing systems.
This agency has been given specific responsibility
for helping farmers improve the grazing
lands of the United States. Most states
have at least one NRCS Grazing Lands Specialist
to carry out this mandate. You can find
more information about this initiative at www.glci.org/.
|
On the other hand, improving management
of an existing pasture is usually preferable
to starting a new one. The cost to
seed, till, and control weeds for a new pasture is expensive and must be considered.
Additionally, a producer must consider the
cost to keep livestock off the acreage during
the establishment period. The risk of
erosion during this transitional period must
also be taken into account. In short, it may
be more economical, and less disruptive to
the soil ecology, to improve an existing pasture’s
forage by introducing desirable species
using no-till seeding methods.
GOAL OF GOOD GRAZING
MANAGEMENT:
The maximum number of animals has plenty
of good quality forage to graze throughout
as much of the year as possible. The needs
of the soil, the plants, and the livestock are
balanced to achieve this goal.
KEY TOOLS OF GRAZING
MANAGEMENT:
- Stock density
- Frequency of moves
- Paddock rest
|
Many pasture problems – such as sparse
plant cover, weed invasion, and slow
growth – are caused by poor grazing management.
If this is the case, establishing
a new pasture will not solve the problem.
Newman Turner, in Fertility Pastures and
Cover Crops, observes that good grazing
management can transform poor grazing
land into healthy, productive pasture. On
the other hand, newly re-seeded pastures
quickly become poor again under bad management.
(1) Thus, a careful assessment of
management practices is usually the best
place to begin to make forage systems more
profitable.
Choosing a Grazing System
Many managers use controlled grazing plans instead of continuous grazing to increase forage utilization and profits. In a system of controlled rotations, pastures are subdivided into paddocks fenced acreage of any given size. Livestock is moved between paddocks at frequent intervals, giving animals access to a limited pasture area over a short period of time.
The animals do not return to a paddock
until the plants have recovered and regrown
to the desired height for grazing (usually six
to eight inches). As a result, the plants have
time to recover, the roots maintain energy
reserves, and the livestock always have high
quality forage.
Knowledge of forage plants and animal-pasture
interaction is necessary to the success
of this type of grazing plan – and frequent
attention to both is essential. This is
why these programs are often referred to as
“management-intensive” grazing systems.
Controlled, intensive, and rotational grazing
are other terms loosely used for this
type of grazing management. The subject
of grazing management is covered more
completely in the ATTRA publication Rotational
Grazing.
Knowledge
of forage
plants,
and animal-pasture
interaction is necessary
to the success
of a controlled
grazing plan.
|
Rotations can vary from once every couple
of weeks to every 12 hours. Decisions
about when to move livestock are based on
the seasonal amount of forage available, the
rate of forage growth, and the number and
type of animals grazing the paddock. The
number and size of paddocks is also considered.
Typically, grazing animals are moved
quickly through paddocks during periods of
rapid plant growth. In the fall, quick rotations
keep grasses from going to seed and
preserve forage quality. This strategy can
delay for several weeks harvesting of forage
as hay, allowing for hay to be put up during
a dryer time of the season. During other
seasons, the grazed area is usually rested
long enough for plants to replace carbohydrate
reserves and to regrow.
A primary strategy of controlled grazing
is to use fencing and
livestock movement
as tools to manage
forage growth and
protect it from overgrazing.
If managed
well, these systems
produce more forage
and the animals
always have access to
tender, high-quality
vegetation that results
from controlled
grazing.
Profit is the difference between the cost of
production and the price received for a product.
Most producers do not control the price
they will receive for their livestock (though
direct or cooperative marketing arrangements
provide a measure of control). Lowering the
cost of production is a clear means to increase
profit. Costs go down as less feed is purchased
and as animal health improves. The key to
profitability is to emphasize a decrease in per-unit
costs of production over a simple increase
in production. |
Many grazing managers – or graziers – claim
that controlled rotational grazing improves
pastures and the profits to be made from
them. Forage utilization improves even
under high stocking rates when the animals
are moved at the right times. Livestock
health improves because forage quality
and quantity is better. Soil fertility is better
because most nutrients cycle through the
animals and remain in the paddocks. This
can also reduce the need for purchased fertilizer.
(See the ATTRA publication: Nutrient
Cycling in Pastures.) More and better forage
means more animal production, which
should result in more profit per acre.
A change to controlled grazing involves a
modest capital investment. (See ATTRA’s
Paddock Design, Fencing, and Water Systems
for Controlled Grazing.) This may include
buying and installing electric fence chargers,
high-tensile wire fencing, and systems
to provide water to each pasture subdivision.
A simple system of temporary electric
fencing may suffice at the outset for many
producers. Water can be delivered initially
in above-ground, UV-stabilized pipe. With
experience, most graziers will settle on how
the permanent systems should be configured.
For more information on controlled
grazing call ATTRA at 800-346-9140
(toll-free), or visit the ATTRA Web site.
Changes in the Plant
Community
In a continuous-grazing system where animals
are given free choice, they will eliminate
the most nutritious or palatable plant
species, because they graze them repeatedly.
Root reserves of these preferred species
are eventually exhausted, and the
plants die out. Fescue, bermudagrass, and
white clover persist under continuous grazing
because their growing points remain,
even when the plants are grazed heavily.
After three years of controlled rotational grazing, analyze the results. |
In a controlled-grazing system, animals
don’t have access to all the plants in the
pasture at one time. Plants are allowed sufficient time to re-grow and restore their root
reserves. Eventually, the plant community
becomes more diverse under this type of
grazing system. There is less competition
for the same soil minerals, and plants thrive
in the specific microclimates where they are
best adapted. Producers report that native
grass species and many legumes spontaneously
appear in their pastures as rotational
grazing systems are adopted. In fact, many
advise new graziers to “plant only fence
posts” in the first three years of intensive
rotational grazing, because the plant ecology
will change – for the better.
After three years of controlled rotational
grazing, analyze the results. Should new
forages be added to the pasture to meet
specific production or management goals?
If a goal is to extend the grazing season to
reduce feed costs, new species might be
added to existing pastures. Special-use paddocks
might also be considered. For example,
in southern pastures with cool-season
grasses, the summer slump is a time of low
forage production and potential health problems,
especially from endophyte-infected
fescue. Native grasses or plantings of summer
annuals can fill this gap in the grazing
season. In the Midwest, the grazing season
may be extended into the winter by strip grazing
crop residue. Stockpiled fescue or
other grasses, if carefully rationed, can support
several extra months of winter grazing,
even where there is some snow cover. Small
grains offer options for fall, winter, and/or
spring grazing, depending on regional climate
conditions.
Managing Fertility
Grazed pastures need less fertilizer than
those that are hayed. Animals actually use
up very few of the nutrients from the plants
they eat. Most minerals are returned in
animal wastes as part of a natural cycling
of nutrients. Phosphorus is excreted primarily
in manure, and nitrogen and potassium
return in urine and manure. As long
as wastes are evenly distributed throughout
the grazing area and biological agents such
as earthworms, dung beetles, and soil bacteria
are active, the system should be relatively
stable.
Good fertility management includes a regular
walk through the paddocks to monitor
pasture production and to see where specific grasses and legumes thrive. Notice
that certain plants tend to thrive under certain
soil moisture and fertility conditions.
The types and locations of weeds can also
indicate how a fertility program is working
and help identify special situations such as
wet areas. (2)
Conscientious grazing managers record
measurements or estimates of available
pasture in each section. Using these figures,
they budget resources for the future,
taking into consideration the amount of rest
needed before the next grazing period, as
well as the animals’ forage needs.
Various plants contribute to soil fertility.
Legumes increase the total nitrogen content
of the soil (see discussion below). Deeply
rooted plants such as alfalfa, warm-season
grasses, trees, and some weeds bring
up other nutrients from deep in the subsoil.
These nutrients remain in the top layers
of the soil when the vegetation decays
and then become available to other plants
nearby. (See Trees in Pasture Systems in
the Appendix for more about the benefits
and potential problems related to trees in
pastures.)
Periodic soil tests and forage analyses are
tools to monitor a pasture's status. Soil test
results indicate the levels of mineral nutrients
in the soil. Forage analysis is a way
to test whether nutrients present in the
soil are actually being used by the plants.
Many Extension offices offer forage analyses;
when requesting this service be sure
to specify whether test results will be used
to balance a feed ration or for soil fertility
decisions. Independent laboratories are
available if your local Extension doesn’t
offer this service. The ATTRA publication
Alternative Soil Testing Laboratories is available
online or upon request.
Soil test results include fertilizer recommendations
based on information the farmer
provides about field history and planned
use. Remember that these recommendations
can vary depending on assumptions
by the lab. For example, a recommendation
may not be entirely accurate to produce
grazing forage if the lab doesn’t take
into account recycled nutrients by the grazing
animals. Lab fertilization recommendations
may be over- or underestimated,
depending on whether forage is harvested
and removed or grazed on site. Use common
sense to interpret soil tests, but keep
them to monitor changes in soil chemistry
and nutrient levels.
A special test to determine micronutrient
levels may have to be requested. It is good
to check these levels, since they can be
critical to soil – and animal – health. When
soils show deficiencies in essential micronutrients,
supplement either the animals
and/or the soil.
A simple pH
adjustment
can increase
mineral availability
in most soils. |
Soil organic matter (SOM) is monitored to
determine the general health of the soil
and its biological residents. You may have
to request and pay extra to include SOM in
your soil test. On the soil test report, SOM
includes any living or partially decomposed
materials, as well as humus, the final product
of biological activity. When SOM is
relatively high, it contributes nitrogen and
helps make other mineral nutrients more
available to plants. Adding composted animal
manure is one way to increase SOM.
Likewise, leaving a thin layer of organic
residue on the soil surface contributes to
SOM, and it shades the soil and feeds the
soil organisms. (More about soil organic
matter can be found in the section below.)
Some simple methods to assess soil characteristics
require just a shovel and a few
other widely available pieces of equipment.
The ATTRA publication Assessing the Pasture
Soil Resource describes several tests
that can be used periodically for a quick
assessment of the soil.
Soil Amendments
Carefully consider whether purchased
amendments are economically justified. If
soils are the limiting factor, buying inputs
to improve the soil is a wise, long-term
investment. In such cases, improvement
in soil fertility is key to building a dense, lush, and healthy pasture. Such pasture
provides good nutrition to grazing animals,
and wastes contribute to further build the
productivity of the land.
A simple pH adjustment can increase mineral
availability in most soils. Legume
growth in mixed pastures that tend toward
acidity will benefit, and in turn increase
available nitrogen and add more organic
matter to the soil. Lime is used to raise the
pH, but also is an important source of
calcium. It is also less expensive than
many other purchased fertilizers. The
ratio of calcium to magnesium and
potassium is important in itself. See
the enclosure “Lime, the Forgotten
Fertilizer” for more information on
this subject.
Composted animal manure might
also be an excellent investment
because it adds fertility and benefits
soil microbes. However, if manure
is applied to the same pastures over
many years, phosphorus can build up.
Excessive phosphorus levels in soils
and the threat of phosphorus-saturated
soils leaching soluble phosphorus
are serious concerns in some parts
of the country. See ATTRA’s Nutrient
Cycling in Pastures for details on the
phosphorus cycle and how graziers
can prevent phosphorus pollution of
surface and ground water.
One situation where fertilizer purchases
are often appropriate is in
grass dairy operations. Because grass dairies
compete with grain-fed systems, producers
must provide continuous access to the
highest feed value forage available. Likewise,
grass-finished meat animals should
have plenty of high-quality pasture to gain
weight quickly and consistently during
the finishing period. Both of these enterprises
have potential for good profitability
when well managed. Nevertheless, fertilizer
inputs are justified only if existing pastures
are under full use. The important point is
to base decisions on an analysis that compares
input costs to the profits or overall
benefits that might be generated.
Another excellent resource to understand
fertility in grazing systems is Nutrient
Cycling in Forage Systems, the proceedings
of a 1996 conference in Missouri.
See Additional Resources (under Joost
and Roberts) for ordering information.
ATTRA also offers Sustainable Soil Management and Assessing the Pasture Soil
Resource for more on pasture fertility and
monitoring.
Organic Matter
Some recent research has focused on the
many organisms that make up a healthy soil
ecosystem. Plant root systems work together
with tiny plants and animals underground
in a complex, highly organized system very
similar to the one above ground. The soil
biological community includes large populations
of many species of bacteria, fungi,
nematodes, mites, and other microscopic
animals. Balances among the populations
are maintained by variations in the amount
of food available for each part of the system.
Elaine Ingham, Ph.D, a soil microbiologist,
has named this system the Soil
Foodweb.
Ingham offers a service to test soils for
the presence of various organisms. (3)
However, she says a grazier can monitor
pasture soil health just by testing for
soil organic matter (SOM) content, which
includes carbon contained in living organisms,
fresh plant and animal residues, and
soil humus. This type of test measures the
percentage of soil (by weight) that is SOM.
Because organic matter levels are harder to
maintain in warmer, more humid climates,
what constitutes a “high” or “low” percentage
varies in different parts of the country.
Local Extension personnel or soil scientists
can help define these relative values.
A single test establishes a beginning
point, and subsequent tests show whether
soil organic matter is increasing. See the
box Building Organic Matter for ways to
increase soil organic matter, along with
practices that decrease it. Avoid practices
that adversely affect the number of earthworms
in the soil. In fact, counting earthworms in a shovelful of soil is an easy way
for farmers to monitor soil health. Increasing
worm numbers indicates progress
toward the goal of a healthy, biologically
active soil.
Building Organic Matter
These items add organic matter:
• Plant roots
• Plant residues
• Green manures
• Animal manures
• Other organic “wastes”
• Hay and other feed brought in
These things destroy organic matter:
• Tillage and bare ground
• Some pesticides
• Compaction
• Continuous cropping
|
Legumes in the Pasture
Legumes increase soil fertility, improve
overall feed value of available forage, and
extend the grazing season. Bacteria that live
in nodules on the legume roots convert nitrogen
in the air to a form the plant can use.
After the nodules separate from the roots
or the plant dies, this nitrogen is available
to nearby plants. Even during the growing
season, dead leaves fall to the ground and
provide extra nitrogen to the pasture system.
Compared to grasses, legumes have
higher digestibility and higher mineral and
protein content.
When introducing legumes into an established
grass pasture, first be sure that magnesium
and potassium levels are suitable.
Then graze the area heavily to set it back.
Many producers use a sod-seeder or other
no-till seed drill, but some have had luck
with frost seeding. This is the practice of
broadcast seeding in very early spring into
areas where the ground alternately thaws
and freezes. Timing must be good to take
advantage of these temperature swings.
These are conventional practices, and information
is widely available about them.
For legumes to prosper in a pasture, the
grass must be kept short enough that
they are not shaded out. Nitrogen fertilizer
favors the grass, and you can inadvertently
reduce the percentage of legumes
in the pasture mix by adding it. Each
species of legume thrives in a particular
pH range, but maintaining it between
six and seven favors most legumes. Some
legumes, such as lespedeza, tolerate more
acid conditions.
When
introducing
legumes into an
established grass
pasture, first be sure
that magnesium
and potassium levels
are suitable. |
Many annual clovers produce hard seed
and will persist in a pasture if allowed to go
to seed periodically. (It is this “hard seed” that accounts for the legumes that seem to
appear from nowhere in pastures where
management has changed, but no legumes have been planted.) Annual legumes that
do not produce hard seed must be managed
to allow some plants to go to seed
every year to keep them in the forage mix.
Beyond this, providing for the nutritional
and light needs of legumes, along with adequate
rest after harvest, should ensure their
persistence.
If the legume is established and maintained
at about a third of the total pasture, the
plants won’t need additional nitrogen fertilization.
Research at Michigan State University
shows that different combinations of four
cool-season grasses with three clover species
produce, on average, 14 percent more
forage than the same grasses grown alone
and fertilized with 200 pounds per acre of
nitrogen. The conclusion is that it doesn’t
pay to apply nitrogen to pastures with 30
percent or greater mix of legumes. (4)
However, it’s hard to estimate legume percentage,
because the leaf orientation makes
it seem a higher percentage of total forage
than it actually is. To better estimate overall
percentage, sample and weigh plants in an
area with a lot of legumes.
Remember, hungry animals introduced to
highly leguminous or wet legume pastures
may bloat. To prevent this problem, provide
hay to animals before they access a legume
pasture. Certain products on the market
protect livestock from this potentially deadly
physiological condition. Since bloating is
inherited, if you cull susceptible animals,
you may eventually reduce the problem in
your herd.
Managing Weeds
In a controlled-grazing system, livestock can
help control tall weeds that re-seed themselves.
Because animals have access to a
limited area for only a short period, they
often become less selective in their grazing.
They tend to eat the same weeds – in young,
tender growth stages – that they reject as the
weeds mature. Many weeds provide good
nutrition during this period of palatability.
Mowing before weeds flower and produce
seed also helps to control them, although
the cost is higher.
Grazing Cattle and Sheep
Courtesy of USDA ARS |
Another weed management strategy is to
graze different kinds of livestock together.
Sheep will complement grass-eating cattle
in the pasture by consuming broadleaves,
blossoms, and seeds, while goats prefer
brushy vegetation high in cellulose. Information
about animals’ nutritional requirements
and the nutrient content of various
forages is available from basic forage and
animal science textbooks. For more information
on the benefits and challenges of grazing
mixed livestock, request the ATTRA
publication Multispecies Grazing.
A growing number of beneficial insects is
becoming commercially available to control
thistles and some other perennial weeds.
These weed-eating insects are especially
adapted to a perennial pasture where habitat
is not destroyed or disturbed by annual
cultivation. If local sources are unable
to help, ATTRA has information about
biological management tools and where
to get them.
Tall perennial weeds that livestock do not
eat can be controlled with the judicious
application of a broad-spectrum herbicide,
such as Round-Up®. Hand-held sprayers
will work, but a wick-type applicator places
the chemical on the targeted weed foliage
only. Hand-held wicks are available as well
as equipment designed to be pulled behind
a tractor or four-wheeler. Also on the market
are backpack flaming devices that actually
burn the weeds and provide a non-toxic
option to control difficult weeds. ATTRA
publications Flame Weeding for Agronomic
Crops and Flame Weeding for Vegetable Crops provide more detail about this option.
Conserved Forages vs. Grazing
Providing good-quality forage throughout
the year saves considerably on feed costs.
Year-round grazing is possible in some parts
of the country and is a realistic goal in some
regions. Many producers, even those in
cold climates, report favorable experiences
with attempts to “outwinter” their livestock.
Adequate feed and shelter from wind and
moisture are critical. Reports indicate that,
under favorable conditions, animals seem to
prefer being outside where they can forage
at will.
A sustainable pasture plan should be based
on animals harvesting quality forage for
themselves as much as possible. Nevertheless,
when spring pastures produce more
than livestock can use, machine harvest is
one strategy to ensure quality forage later in
the grazing season.
Allan Nation, editor of The Stockman Grass
Farmer, is fond of questioning the economics
of owning “heavy metal.” It is expensive
to maintain equipment and to harvest
forage for hay or silage, so it is sometimes
more economical to buy hay or hire a custom
baler. However, it can be difficult to
find someone to custom harvest and process
spring growth at the optimal time.
Another challenge to a spring hay harvest is
the weather. A spell of good haying weather,
if it comes at all, rarely arrives at the perfect
time. One option in wet conditions is to
harvest, pack, and seal the excess spring
grass in bunkers for fermentation. Livestock,
controlled by a single wire of electric
fencing, can then have direct access to the
silage bunkers.
Some producers advocate baling high-moisture
hay and wrapping it so that it will ferment.
Baleage, as the product is called, is a
high-quality feed when properly harvested
and protected from air spoilage. This is one
way to harvest on time in wet springs. However,
specialized equipment is expensive for
one producer to own and operate, and rental
may not be available. Several producers in
an area with similar needs might recover some costs through contractual arrangements
among themselves. The amount of
plastic used to seal cut forage is a concern
for many farmers as well, since it must be
disposed of after use. For more information
on grass silage or baleage, contact a local
Extension office or NRCS personnel.
In summary, conserving forages can help
manage fast-growing spring pasture, and hay
or silage is useful to carry livestock through
some of the year in most parts of the country.
However, the goal should be to directly
graze as much as possible to avoid the costs
to harvest and store forage. Custom harvesting
or even buying good hay may be cheaper
than maintaining a tractor and implements.
(See the enclosed article by Jim Gerrish on
the true cost of hay.)
Considerations for
Irrigated Pasture Systems
in the Western U.S.
Many regions in the western United States,
including intermountain valleys of the
Rocky Mountains, the prairies of the northern
Great Plains, and certain arid regions
of the desert Southwest, experience short
grazing seasons due to high elevation, limited
moisture, or a combination of both.
Livestock producers in these regions find
it particularly important to manage forage
and pasture in the most efficient way possible.
By integrating irrigated pasture with
dryland pasture, range, and hay aftermath,
the grazing season can be lengthened and
livestock provided with high yields of quality
forage.
The Essentials
Conventional wisdom holds that one acre
of irrigated pasture in most intermountain
valleys provides enough forage for twelve
cow-calf pairs for one month. But unproductive
irrigated pastures are more the
norm, and few producers maintain pasture
to its full potential. Productive irrigated
pastures are usually the result of successful
management of several production factors,
including:
- fertility
- irrigation
- species selection
- grazing management
These factors can be managed.
Fertility
Attention to soil fertility is critically important
in irrigated pastures. Pasture establishment
is a key time to ensure soil is adequately
fertile for the selected forage species
to become established and remain productive.
During secondary tillage, rock minerals,
composted manure, or commercial fertilizers
can be incorporated into the soil. In
the intermountain regions, it is important
to ensure adequate phosphorus and potassium
before planting, but nitrogen should
be applied early the second spring. Cool,
dry springs are difficult on grass seedlings,
and nitrogen applied at this time may be
appropriated by weeds.
Apply nitrogen only after the grass stand
is successfully established. If the stand has
a legume component, limit the use of synthetic
nitrogen fertilizers. In general, nitrogen
fertilization favors grass growth, and
phosphorus fertilization favors legumes.
Yearly applications of 20 to 50 pounds
per acre of phosphorus can significantly
increase alfalfa yields and stand persistence
in areas deficient in phosphorus. Soil
tests are fairly reliable to gauge phosphorus
needs, but again, modern soil testing
assumes the forage will be harvested and
fed on site. Don’t underestimate the utility
of the mineral fraction of nutrients in the
soil, and the natural nutrient cycle that supports
pasture ecology.
Some nutrients do leave the pasture system in the form of meat and milk. |
Whereas most soil nutrients are cycled back
to the soil in a grazing system, some nutrients
do leave the pasture system in the form
of meat and milk. More information on fertility
and nutrient cycling can be found in
the ATTRA publication A Brief Overview of
Nutrient Cycling in Pastures.
Irrigation can also have an effect on nutrient
cycling. Coarse, porous soils do not
retain water as readily as heavier soils, and heavy irrigation can leach nutrients into the
groundwater. If the pasture has any slope
to it, nutrients can leave in runoff. Ditches,
dikes, and proper irrigation scheduling can
alleviate this problem.
Grass-legume mixes provide good pasture
productivity and animal nutrition and aid
nutrient cycling and pasture fertility. Pastures
with a heavy clover component can
produce up to 200 pounds of nitrogen per
acre per year, and can supply 6 to 12 percent
of the nitrogen needs of companion
grass plants during the growing year. Given
these prospects, a producer can optimize
the use of soluble and organic soil nutrients
by relying on plant species diversity
and nutrient cycling from manure, urine,
and plant senescence to supply a large portion
of pasture soil fertility. More detailed
information on this subject can be found
in the sections Managing Fertility and
Organic Matter.
Irrigation
Efficient water use is crucial for sustainable
irrigated pasture management. Irrigated
pastures require about 24 inches of water
per growing season. What is not supplied
by precipitation needs to be made up with
efficient irrigation. Grasses and legumes
require about 0.20 and 0.25 inches of water
per day respectively throughout the growing
season. So, frequency of irrigation depends
on soil texture and, in turn, on water holding
capacity of the soil.
Heavier (clay) soils hold more water, up to
2.5 inches per foot of rooting depth, and
coarser (sandy) soils hold less water, around
0.75 inches per foot. Pastures have an effective
moisture depletion allowance of about
65 percent, which means plants begin to
suffer stress after 65 percent of the soil’s
water-holding capacity has been depleted.
For example, pasture soil with a water holding
capacity of 1.5 inches per foot, and a
rooting depth of four feet, can hold a total of
six inches of water. At a 65 percent depletion
allowance, 3.9 inches remains available
to the plants. If the plants use 0.25 inches
per day, an irrigation event that saturates
the soil will last about 15 days.
Understanding the basics of soil-water
dynamics helps producers make decisions
on when to irrigate, especially in
areas where water is scarce or energy
costs for pumping are high. The Agrimet
system (see Electronic Resources) is an excellent
resource for producers making irrigation
scheduling decisions. In addition,
the Natural Resource Conservation Service
(USDA-NRCS) district offices have
access to each county’s soil information
and can assist producers to determine the
water holding capacity of soil types on
area farms. The Irrigator’s Pocket Guide,
developed by NCAT for the NRCS, is an
excellent resource with timely information
on irrigation scheduling, system capacity,
and general water management. It includes
figures, forms, and tables to design and
manage water systems more efficiently.
The Pocket Guide has useful information
for most areas. It can be ordered from
ATTRA by calling 800-346-9140. Other
ATTRA publications on irrigation include: Soil Moisture Monitoring: Low-Cost Tools and Methods and Measuring and Conserving
Irrigation Water.
Always remember to irrigate a pasture
immediately after the livestock have been
moved, and never irrigate and graze at
the same time. Hoof action on wet soil can
destroy its structure, resulting in compaction
and decreased soil productivity for
years to come.
Species Selection
The importance of choosing the right
plants to use in an irrigated pasture
cannot be overstated. The high cost of
irrigation, including initial equipment
purchase, energy, and maintenance
demand that a producer select the most
productive plant species for the region.
In some situations, short season problems
and low yields can be addressed
though proper species selection. Choose
long-lived, winter-hardy forage plants
adapted to your specific soil type. Plants
should be capable of high yields and have
the genetic potential to withstand grazing
and regrow quickly.
Species diversity is also important, as was
discussed in detail earlier. Greater productivity
and increased biodiversity are fostered
through grass-legume mixes. A grass component
in a legume pasture can also minimize
health problems associated with bloat.
Some non-bloating legume species include
cicer milkvetch, sainfoin, and birdsfoot trefoil.
For the intermountain West, a mixture
of two grasses and one legume provide as
many, or more, benefits to pasture productivity
as do more diverse pastures in higher
rainfall areas.
Choose the right species for the mix, however,
because species that mature at different
times can result in low quality forage.
Creeping foxtail and timothy are both
excellent irrigated pasture grasses, but foxtail
matures several weeks before timothy.
Red clovers and vetches usually do not persist
as well as alsike clover, white clover,
and alfalfa in the intermountain regions.
Some good substitutes for alfalfa in irrigated
pastures are sainfoin and birdsfoot
trefoil, which, unlike alfalfa, are tolerant of
high water tables. A very common seed mix
for irrigated pastures in the intermountain
West is meadow brome, orchardgrass, and
alfalfa.
Warm-season grasses are sometimes a good
choice for the Southwest and Great Plains,
and can result in substantial livestock gains
and milk production when managed intensively.
Warm-season annuals such as sorghum
and sudangrass are good choices for
rotational or strip grazing, and are very
good if the pasture is used in a crop rotation.
Cool-season grasses such as brome,
ryegrasses, timothy, and cereals are often
higher in digestibility and crude protein,
and are more adapted to intermountain,
inland Pacific Northwest, and Great Plains
regions.
Check with your local county Extension
office or conservation district for recommendations
on forage species particular to your
area. For general purposes, please refer to
the Alberta Forage Manual and the Intermountain
Planting Guide cited at the end
of this publication. These two guides are
excellent sources of information for anyone
growing pastures and forages in the intermountain
West or northern Great Plains. A
list of forage species for Montana and Wyoming –
widely adapted to irrigated pastures
in many western states – is enclosed.
Forage Cropping Systems to
Extend the Grazing Season
Many western ranchers grow alfalfa hay to
provide high quality feed to late-gestation
and calving cows in the winter. Most alfalfa
fields remain productive for six to eight
years in the intermountain West. As sward
density diminishes, the stand is generally
terminated and placed into small grains for
a year or two. This rotation has its benefits.
Tillage and crop differentiation allows the
producer to break the pest cycle. And termination
of an alfalfa field offers an opportunity
to augment ranch forage assets with
quality pasture while extending the grazing
season as well.
For example, a producer might terminate
the alfalfa and plant winter wheat in the
fall, and then overseed the field with annual
ryegrass in the spring. The wheat can be
taken as grain, silage, or hay in the summer,
allowing the ryegrass to grow for late
summer and fall grazing. The same can be
done with spring-planted barley. The result of this cropping system is a high quality pasture
that can be intensively managed with
high stocking rates, thereby resting native
pastures that might otherwise be grazed the
same time each year.
Hayfield
Lee Rinehart |
Other systems that work well to extend the
grazing season:
- Stockpiling perennial grass or
legume forage for fall grazing.
- Early season grazing of winter wheat
and subsequent grain harvest.
- Planting perennial grass pastures for
use as winter standing forage, e.g.,
Altai wildrye, which maintains quality
well when dormant and stands up
under a snow load.
Fertility and species selection are important. But the single most important factor
to increase production on irrigated fields is a workable grazing management system
that meets the nutritional needs of livestock and maintains the pasture sward
in the vegetative stage throughout the grazing season. |
Grazing Management
Rangeland
Courtesy of USDA, NRCS |
Complementary grazing is a system in which
livestock are grazed in annual or perennial
seeded pastures in the spring and fall, and
are taken to native range in the summer
when the native grasses are in their prime.
This system uses each pasture when it is at
its peak in quality and quantity, and it is
commonly used in western states to supplement
range and extend the grazing season.
Within this context, western producers are
familiar with continuous grazing. The size
and scope of grazing units, coupled with
the use of public grazing allotments, often
preclude fencing and other necessary infrastructure
to support intensively managed
rotaional grazing. In addition, most producers
who graze irrigated meadows also hay
them once or twice during the growing season,
and only graze
them for hay aftermath.
For this reason,
irrigated meadows
tend not to be
managed intensively
for grazing, as they
are seen to be more
valuable for winter
feed than for summer
grazing. After
all, that is what the
mountain meadows
are for.
However, for the producer who wishes to
scale back on hay production, the irrigated
meadows can be used for grazing during
the growing season, and upland meadows
that consist of bunch grasses like Altai
wildrye can be stockpiled for winter feed.
Altai wildrye typically remains a high quality
forage well into the dormant season, and
large bunch grass type holds up well under
a snowload.
Producers who choose to develop a rotational
grazing system on their irrigated meadows
can realize better animal gains per acre and
reduced feed costs associated with feeding
the cow herd in the winter. See the ATTRA
publication Rotational Grazing for a general
introduction to this type of grazing system.
For most cool-season bunchgrass species,
18 to 27 days rest is adequate for substantial
regrowth without allowing the plants
to become too mature. A problem that can
occur in short-season regions is forage maturing
in the last pastures to be grazed before
the livestock get to it. To deal adequately with
this situation a producer might turn livestock
in to the first pasture early, maintain a quick
rotation, and then slow it down as the season
progresses.
A good formula to estimate an initial pasture stocking rate is:
number of animals =
Pasture size (ac) x pasture yield (lb/ac)
0.036 x avg. animals wt (lbs) x grazing season (days) |
For example, assume a producer has a 50-acre irrigated pasture of orchardgrass,
meadow brome, and alsike clover. A reasonable
expectation of dry matter yield in the
intermountain West is 2.5 tons per acre, or
5000 pounds per acre.
If the producer wants to graze 800-pound yearlings for 90 days, the calculations to figure the stocking rate on an early turn-out to maximize irrigated pasture use is:
number of animals =
50 acres x 5,000 lb/ac
0.036 x 800 lbs x 90 days |
Again, a rapid grazing rotation during the early season is important to consider. At higher elevations, spring temperatures can dip to freezing each night, slowing grass growth. Hitting the pastures too hard too
early can impede the system’s ability to
rebound and deliver good forage production
later in the summer. Another approach
is to decrease the stocking rate until nights
become warmer and forage production
begins in earnest. Like any rotational grazing
system, controlled grazing in the West
requires observation, observation, and more
observation. The Chinese proverb holds true
here: “The best fertilizer for the land is the
footprint of the farmer.”
A Word about Dragging and
Harrowing Pastures
Avoid using irrigated pastures to winter feed
hay unless you plan to renovate, drag, or
harrow in the spring. Feeding grounds are
subject to soil compaction because of the
large numbers of animals that congregate
there over the winter. Harrowing pastures to
distribute manure, although not always cost effective,
is often recommended in short-season
regions, at least once at the beginning
of the growing season. In cold regions with
short growing seasons, nutrients cycle in the
soil at a much slower rate than in more temperate
regions. Manure piles therefore tend
to break down slower, and dragging can
break them up, increasing surface area and,
it is thought, aiding in decomposition.
Summary
Sustainable livestock production in the western
U.S., as in all regions, requires ranches
and farms to rely more on green growing
forages as the primary feed for the operation.
Careful attention to fertility, efficient
irrigation, and grazing season extension
through appropriate forage cropping systems
are effective ways to lower production
costs, reduce off-farm inputs, and build soil
resources. In addition, paying attention to
species selection and implementing a well-organized
and suitable grazing management
system fosters continued resource use in perpetuity,
aids in the financial well-being of the
operation, and ensures that ranching remains
a viable livelihood for the next generation.
Sustaining Excellent Pastures
Maintaining a productive plant community
that can profitably feed livestock requires
attention to the soil, the plants, and the livestock.
Each of these alone contributes to
excellent pastures, but even more importantly,
each affects the others. Too often,
farmers attribute problems in a grazing system
to the wrong forage species or inadequate
fertility, when poor animal-plant-soil
management is the real culprit. Bringing in a
new species or adding fertilizer rarely solves
problems caused by an inattentive manager.
How you manage your grazing livestock,
however, makes a big difference in pasture
improvement. This improved pasture likewise
contributes to better health of those
same animals.
If you don’t already know your soil, get maps
and learn about soil types. Use soil test
results to decide what amendments to apply.
Is your soil organic matter level high or low
for your climate? Is it increasing under your
management?
Can you identify the plants in your pastures?
Are they perennial or annual? Do you
know how best to graze these plants? What
are their soil requirements? How tall should
they be when you begin to graze and at what
height should animals be removed?
How do your animals look and behave? Are
they alert with bright eyes and smooth coats?
Are they skittish or calm? Can you move
them without a lot of stress?
Continually monitor your pastures. Are they
lush and dense? Is there evidence of soil erosion?
Are there many over-mature plants?
Have certain areas been grazed too short?
Is there some dead plant residue on the
soil surface, but not too much? Is leaf color
an even, strong green? Are there plenty of
legumes in the species mix (about 30 percent
by dry weight)? Does the soil feel soft
and springy underfoot? Do you have plenty
of feed for your animals throughout the grazing
season, or are there times (mid-summer?
late fall?) when you need more?
Good grazing management is different for
each livestock operation. Stock density, frequency of moves, forage residual, and plant
resting periods are decisions that you make
based on goals and preferences. Watch and
record what happens as you change one of
these factors. These observations will help
you, as time goes by, to become a better grazier.
Try to understand what causes changes
that you see in the soil, plants, or the animals
in your pastures. Each constantly affects the
others, and the more you learn about how
they interact, the more control you will have
over your pasture system.
Can you identify the plants in your pasture? |
As an example, according to Jim Gerrish,
stock density can be used to affect pasture
quality, to cycle nutrients, and to regulate
forage intake. One expected result of increasing
the stock density is that after the animals
leave a paddock, forage height will become
more uniform.
Since many of the effects of individual decisions
will not yield such obvious results, continually
seek out more information about
intensive grazing. Excellent books, some
periodicals, many workshops, and even local
field days can help you learn more. A list of
written materials and electronic resources is
found in Resources.
Consult with another rancher or join a producer
group to learn more about grazing.
Many such grazier groups provide information
and support to improve members’ systems.
Typically, groups include beginners as
well as those with years of experience. Activities
range from gathering periodically and
walking one another’s pastures, to meetings
with speakers, and seminars. See ATTRA’s
Grazing Networks for Livestock Producers for
further information about these groups and
how to start one. State forage specialists
(either Extension or NRCS) should help you
locate a nearby group, if there is one.
Putting it all together
in a grazing system
for your specific site
is a challenge that
may take years of
observation and
creative problemsolving.
There is no
one way to do it.
Keep learning more
about your forages
and livestock. Seek
ideas from other
innovators and test
them. Implement
those that work.
Keep fine-tuning
the system. The
result will be better
pastures that better
sustain your livestock
and you. |
Keep records of grazing activities. Keep
notes on how many and what types of
animals graze each paddock. Write
down when they enter and when they
leave. Notes about forage heights at entry
and removal, as well as estimates of the
amount of forage consumed (pounds per
acre or some other consistent measure),
help determine overall forage production.
Other comments about the soil, the animals, and the plants can be useful later
as you analyze records. For instance, when
a particular weed species becomes unpalatable
or when clover begins to bloom may be
valuable to know.
Financial records further help you understand
and improve the overall grazing system.
Keep track of how much fertilizer
you use, when it was applied, and how
much it cost. Are there application costs?
What other expenses are there? Veterinarian
bills, custom services, herbicides,
and mowing or dragging expenses should
be included in the record-keeping system.
Were animals shipped or brought in?
When? And for how much?
Grazing Sheep
Courtesy of USDA ARS. |
Whether you use a shirt-pocket notepad
or a computer program, these records are
central to understand and improve the efficiency and profitability of a grazing system.
However, as the manager, you must
take time periodically to analyze records.
What have you done and when? How well
has it worked? Were there unexpected outcomes?
Try to figure out what happened.
The best-laid plans will not be perfect –
especially at first. Outside factors such
as the weather and the markets further
complicate situations.
As has often been said, there is never an
average year. The most successful managers
are constantly on the alert, ready to
identify problems as they develop – such
as thinning pastures or declining livestock
health. Good managers are prepared
with a plan for every contingency: years of
drought or flood, selling or retaining stock
during different parts of the price cycles,
and the unexpected loss of labor. For example:
When a drought sets in, will destocking
or buying feed best serve your goals?
Which animals should be culled first, and
how can they be marketed most profitably?
Are there steps you can take to reduce
the negative impacts of the drought?
Planning along these lines will be appreciated
when the situation is at hand. See
further information about drought management
by searching on “drought” at the
ATTRA Web site.
References
- Turner, Newman. 1974. Fertility Pastures
and Cover Crops. 2nd ed. Bargyla and Gylver
Rateaver, Pauma Valley, CA. p. 18.
- Murphy, Bill. 1987. Greener Pastures On Your
Side of the Fence. Arriba Publishing, Colchester,
VT. p. 207-212.
- Elaine Ingham
Soil Foodweb, Inc.
980 Northwest Circle Blvd.
Corvallis, OR 97330
541-752-5066
www.soilfoodweb.com/
- Leep, Rich, and Doo-Hong Min. 2005. Clovers
beat commercial N in Michigan studies. The
Forage Leader. Spring. p. 11.
- Engle, Cindy. 2002. Wild Health: How Animals
Keep Themselves Well and What We Can Learn
From Them. Houghton Mifflin Company,
New York, NY. 276 p.
Enclosures
Anon. 2001. The grass farmer’s bookshelf. The
Stockman Grass Farmer. June. p. 19–22.
Barnhart, Stephen K. 1999. Selecting Forage Species.
University Extension, Iowa State University,
Ames, IA. 4 p.
Gerrish, Jim. 1999. Strategies for pasture improvement.
Forage Systems Update. January 1. p. 1-3.
Gunnink, Doug. 1993. Gross margin analysis helps
show the way to grazing profits. The Stockman Grass
Farmer. April. p. 14-15.
Holzworth, L., and J. Lacey. 1991. Species Selection,
Seeding Techniques, and Management of Irrigated
Pastures in Montana and Wyoming. p. 9-12. In:
Irrigated Pastures in Montana and Wyoming. EB 99.
MSU Extension Service, Bozeman, MT.
Hoveland, Carl S. 2001. Know your forages…clover.
The Stockman Grass Farmer. January. p. 10-11.
Joost, Richard. 1997. Pasture soil fertility management.
p. 35-46. In: Gerrish, Jim, and Craig Roberts
(eds.). 1997. Missouri Grazing Manual. University
of Missouri, Columbia, MO. 172 p.
Martyn, Roger. 1994. Lime, the forgotten fertilizer.
The Stockman Grass Farmer. March. p. 14.
Mueller, Ray. 1999. Pasture fertilizing practices vary
according to goals, needs.
Sheath, G.W., R.J.M. Hay, and K.H. Giles. 1987.
Managing pastures for grazing animals. p. 65–74.
In: Livestock Feeding on Pasture, New Zealand Society
of Animal Production Occasional Publication No.
10. Private Bag, Hamilton, NZ.
Resources
The Stockman Grass Farmer (see Periodicals, below) is
an excellent monthly publication that covers alternative
forages and innovative management. Many of the
articles are written by producers and contain practical
tested ideas. (Be warned: evaluate each new practice
before committing resources to it.) The commercial
and classified ads offer services and supplies that
grass farmers need and that may be difficult to find
locally. A free sample issue is available to those who
call or write to request it.
Graze (see Periodicals, below) is another outstanding
monthly that includes articles on all aspects of grazing,
pasture management, and marketing. In a regular
feature, five or more “grazing advisors” answer a
question posed by the editor. These advisors, each an
active grazing operation manager, represent a variety
of livestock types and geographical locations.
Holistic Management® (formerly Holistic Resource
Management or HRM) is a decision-making process
that was originally developed for livestock management
on range. Currently, many farmers and ranchers
use this model as a monitoring tool to evaluate
options when planning changes to their operations.
Contact the Center for Holistic Management for
information and referrals to state organizations and
regional representatives. The Center also offers a
quarterly newsletter.
The Allan Savory Center for Holistic Management
1010 Tijeras NW
Albuquerque, NM 87102
800-654-3619
www.holisticmanagement.org/
Many electronic resources are now available to those
with access to a computer. Of particular interest are the
interactive listserves used by various livestock ranchers.
One that is not species-specific is the graze-l listserve.
To subscribe, send a message containing the
words “subscribe graze-l” and your e-mail address
to listserv@taranaki.ac.nz. There are lists specific
to many grazing species as well. Beef-l, dairy-l, and
sheep-l sometimes address issues related to pasture-raised livestock. It is possible to ask questions and to
network with other producers through these and other
lists. However, because details on individuals and their
specific situations may be lacking, advice received on
electronic lists should be carefully evaluated.
Web sites also provide information useful to graziers.
Although these sites are constantly changing, and
there are more each week, several are listed below.
Be sure to check the sites of nearby land-grant universities.
Rotational grazing systems are becoming ever
more accepted in the mainstream. Extension materials
tailored to your state will contain information useful
to both the beginner and the experienced grazier.
Additional Resources
Books: Irrigated pastures in the western U.S.
Alberta Forage Manual. 1992. Print Media Branch,
Alberta Agriculture, 7000-113 Street, Edmonton,
Alberta, Canada. 86 p.
Heitschmidt, Rodney K., and Jerry W. Stuth. 1991.
Grazing Management: An Ecological Perspective.
Timber Press, Portland, OR. 259 p.
Intermountain Planting Guide. USDA-ARS and Utah
State University Extension. AG 510. Contact USU
Extension for ordering information at 435-797-2251.
Books: General pasture management
Ball, Donald M., Carl S. Hoveland, and Gary D. Lacefield. 1996. Southern Forages. Potash and Phosphate
Institute and the Foundation for Agronomic
Research, Atlanta, GA. 264 p.
Barnes, Robert F., Darrell A. Miller, and C. Jerry
Nelson (eds.). 1995. Forages: The Science of Grassland
Agriculture. 5th ed. Vols. 1 and 2. Iowa State
University Press, Ames, IA. 516 p. and 357 p.,
respectively.
Bingham, Sam, with Allan Savory. 1990. Holistic
Resource Management Workbook. Island Press, Covelo,
CA. 182 p.
Blaser, Roy E. 1986. Forage-Animal Management
Systems. Virginia Agricultural Experiment Station
Bulletin. Virginia Polytechnic University, Blacksburg,
VA. 90 p. www.caf.wvu.edu/~forage/books/fams/index.htm
Chessmore, Roy A. 1979. Profitable Pasture Management.
The Interstate Printers & Publishers, Inc.,
Danville, IL. 424 p.
Gerrish, James R., and Craig Roberts. 1999. 1997
Missouri Grazing Manual. Forage Systems Research
Center Agricultural Experiment Station, University of
Missouri. 163 p.
Hodgson, John. 1990. Grazing Management: Science
into Practice. Longman Handbooks in Agriculture.
John Wiley & Sons, New York, NY. 203 p.
Hodgson, J., and A.W. Illius (eds.). 1996. The Ecology
and Management of Grazing Systems. CAB International,
Wallingford, UK. 466 p.
Joost, Richard E., and Craig A. Roberts. 1996.
Nutrient Cycling in Forage Systems. Proceedings of a
conference March 7-8, 1996, Columbia, MO. Potash
and Phosphate Institute and Foundation for Agronomic
Research, Manhattan, KS. 243 p.
Available for $15 from:
Potash and Phosphate Institute
772 22nd Avenue S.
Brookings, SD 57006
605-692-6280
Langer, R.H.M. 1990. Pastures: Their Ecology and
Management. Oxford University Press, New York,
NY. 499 p.
Murphy, Bill. 1998. Greener Pastures on Your Side
of the Fence: Better Farming With Voisin Grazing
Management (4th ed.). Arriba Publishing, Colchester,
VT. 379 p.
Available for $30 from:
Arriba Publishing
213 Middle Rd.
Colchester, VT 05446
Nation, Allan. 1993. Grass Farmers. Green Park
Press, Jackson, MS. 192 p.
Nation, Allan. 1992. Pa$ture Profit$ with $tocker
Cattle. Green Park Press, Jackson, MS. 190 p.
Nation, Allan. 1995. Quality Pasture: How to Create
It, Manage It, and Profit from It. Green Park Press,
Jackson, MS. 285 p.
Ness, Julia Ahlers (ed.). 1998. The Monitoring Tool
Box. The Land Stewardship Project, White Bear
Lake, MN. 45 p.
Available for $45 from:
Land Stewardship Project
2200 Fourth St.
White Bear Lake, MN 55110
651-653-0618
www.landstewardshipproject.org
Nicol, A.M. (ed.). 1987. Livestock Feeding on Pasture.
Occasional Publication No. 10. New Zealand
Society of Animal Production. Private Bag, Hamilton,
New Zealand. 145 p.
Savory, Allan, and Jody Butterfield. 1999. Holistic
Management: A New Framework for Decision Making.
Island Press, Covelo, CA. 616 p.
Turner, Newman. 1974. Fertility Pastures and Cover
Crops. Bargyla and Bylver Rateaver, Pauma Valley,
CA. 202 p.
Voisin, Andre. 1988. Grass Productivity (reprint).
Island Press, Covelo, CA. 353 p.
Wilkinson, J.M. 1984. Milk and Meat From Grass.
Granada, New York, NY. 149 p.
Periodicals
The Forage Leader
American Forage and Grassland Council
P.O. Box 891
Georgetown, TX 78627
800-944-2342
Graze
P.O. Box 48
Belleville, WI 53508
www.grazeonline.com
$30 for 1 year subscription (10 issues)
Hay and Forage Grower
Webb Division
Intertec Publishing Corp.
9800 Metcalf
Overland Park, KS 66212-2215
The Stockman Grass Farmer
282 Commerce Park Drive
Ridgeland, MS 39157
800-748-9808 (toll-free)
www.stockmangrassfarmer.com
Electronic Resources:
General pasture management,
southern and eastern pastures
[Note that these addresses change often.]
The Great Lakes Grazing Network
http://cdp.wisc.edu/Great Lakes.htm
Cornell Forage-Livestock System
www.css.cornell.edu/forage/forage.html
Penn State College of Agricultural Sciences
Publications
www.das.psu.edu/publications/
American Farmland Trust’s Grassfarmer Site
http://grassfarmer.com
University of Wisconsin Forage and Extension Links
www.uwex.edu/ces/forage/links.htm
Forage Systems Research Center
http://pubs.cas.psu.edu/Subject.htmlaes.missouri.edu/fsrc
Tom Trantham’s Twelve Aprils Dairying
www.griffin.uga.edu/sare/twelve/trantham.html
Modern Forage Seeds
www.modernforage.com/clasroom.htm
Sustainable Farming Connection’s Grazing Page
www.ibiblio.org/farming-connection/grazing/home.htm
Electronic Resources: Western irrigated
pastures
Holzworth, L., and J. Lacey. 1991. Species Selection,
Seeding Techniques, and Management of Irrigated
Pastures in Montana and Wyoming. (PDF / 54K) Download Acrobat Reader. Montana
State University Extension. EB 99. 17 p.
http://animalrangeextension.montana.edu/articles/Forage/grasses/mteb99.pdf
Small Pasture Management Guide for Utah. (PDF / 1.5MB) Download Acrobat Reader. USDA/
NRCS, Utah State University Extension, and Utah
State Conservation Districts. 11 p.
http://extension.usu.edu/files/agpubs/Pasture.pdf
Interagency Forage and Conservation Planting Guide
for Utah. (PDF / 1.55MB) Download Acrobat Reader. Edited by Howard Horton, USDA/ARS.
Utah State University Extension. AG-433. 79 p.
http://extension.usu.edu/files/agpubs/ag433.pdf
Lundin, F. 1996. Coastal Pastures in Oregon and
Washington. (PDF / 209K) Download Acrobat Reader. Oregon State University.
EM 8645. 8 p.
http://eesc.orst.edu/agcomwebfile/edmat/EM8645.pdf
Frost, B. and M. Schneider. 1994. Establishing irrigated
pasture at 4000- to 6000-foot elevations in Arizona.
(PDF / 46K) Download Acrobat Reader. Arizona Cooperative Extension. #194028. 6 p.
http://cals.arizona.edu/pubs/natresources/az9428.pdf
Redmon, L. 2003. Forage Establishment, Management,
and Utilization Fundamentals. (PDF / 3.84MB) Download Acrobat Reader. Texas Cooperative
Extension. SCS-2003-07. 8 p.
http://forages.tamu.edu/PDF/scs-2003-07.pdf
Water Quality and Irrigation Management. Department
of Land Resources and Environmental Sciences.
Montana State University.
http://waterquality.montana.edu
The Great Plains Cooperative Agricultural Weather
Network. U.S. Dept. of the Interior.
www.usbr.gov/gp/agrimet/index.cfm
AgriMet is a network of more than 90 automated
weather stations that collect and telemeter sitespecific weather data. This information is translated
into crop-specific water use information.
The primary emphasis is on irrigation management
and applying the right amount of water at
the optimal time.
Electronic Listserves
Graze-L
To subscribe send an e-mail to
majordomo@taranaki.ac.nz or listserv@taranaki.ac.nz.
In the body of the e-mail, type “subscribe graze-l”
The Grazer’s Edge
To subscribe send an e-mail to
grazersedge-subscribe@onelist.com.
In the body of the e-mail, type “subscribe
grazersedge.”
APPENDIX: Trees in Pasture Systems
Trees in a pasture provide several services, but they
can also be challenging. They affect soil fertility, hold
surface soil in place, give livestock relief from the sun
and the wind, and change water relations. They can
supplement other feed sources, increase wildlife habitat,
and become an additional source of income.
Trees gather nutrients from a large area to sustain both
above- and below-ground parts and deposit those nutrients
on the soil surface. Tree roots go deep into the soil
and spread underground at least as far as the edge of
the leaf canopy. When the leaves fall, the microorganisms
in the top layer of the soil convert them into nutrient
forms to be used again by the tree and by nearby
forage plants. Tree roots continually grow and die. The
dead roots are broken down in the soil and contribute
directly to organic matter, increasing water retention
and improving soil structure.
Shade trees in pastures can be a benefit, but they can
also create problems. It is cooler under the trees, and
livestock tend to congregate there. These areas become
nutrient sinks. That is, nutrients gathered during grazing
are later deposited under the trees as waste. This
nutrient transfer from open pasture to under the trees
reduces pasture productivity. These and other areas of
high animal concentration or repeated use (like around
water and minerals) also tend to accumulate parasites,
which then reinfest the livestock. Livestock concentrating
around a tree can also lead to compaction around
the root zone and result in the loss of a tree.
Although no studies have shown that providing shade
for livestock results in a production benefit, most producers
like to make it available for the comfort of the
animals. The “shademobile” is an innovative idea, promoted
by Joel Salatin, designed to use shade to control
where nutrients will be redeposited. It is an open-sided
structure with a canvas or shade cloth cover that
is towed by a tractor from paddock to paddock. Moving
the shade around constantly changes the loafing area
and controls where manure is deposited, while preventing
parasite build-up.
Windbreaks in or around pastures should be planned
to provide shelter from cold or hot, drying winds and
to protect newborns from harsh weather.
Windbreaks
that include several species of shrubs and trees become
valuable wildlife habitat. The resulting wildlife create
an opportunity for spin-off enterprises such as lease
hunting or bird-watching.
Plants and animals make their homes in all levels of
tree canopies and understories. The birds help control
insect pests, and some eat weed seeds. Larger predatory
birds help control small-mammal populations.
Birds roosting in trees even add their phosphorus-rich
droppings to the nutrient cycle. This biological diversity
increases the stability of the ecosystem and mediates
against the disasters that monocultures are subject to.
To avoid the problems associated with shade, some
farmers fence the tree area so that animals can’t use
the area at all. Or you can remove trees’ lower limbs,
so the shaded area moves across the pasture as the sun
crosses the sky, and animals must move to follow it. The
result is a more uniform pattern of waste distribution.
Trees can reduce erosion on hilly land. If planted in
strips along the contour, they create a natural terracing
effect. Over time, organic matter will accumulate
along the line of trees, and the slope will become more
productive and stable. As an added advantage in dry
seasons, more water is stored underground in these terraced
systems.
On the other hand, when they are planted in wet areas,
trees collect water in their extensive root systems
and “pump” it out through the leaves by transpiration.
Poplars and eucalyptus have been used to reduce surface
salinity in areas where water lies too close to the
surface.
Agroforestry is a term applied to farm systems that
intentionally integrate trees as an additional enterprise
or for their environmental services. Nut trees or
high-value timber are especially popular in pastures.
Although trees require additional care and management,
they can provide a long-term source of additional
income. With good management – particularly attention
to marketing – both nuts and thinnings provide sources
of income before the final timber harvest.
While the trees are still young, row crops may be grown
between them. When the canopy begins to close, and
light is inadequate for row crops, forage crops can be
grown for hay. When the trees are large enough that
they can’t be damaged by livestock, the area can be
directly grazed. This reduces mowing costs while contributing
to fertility for tree and forage growth.
Small trees need protection from livestock and deer.
Deer, like domestic livestock, browse on young tree
growth and will eat any parts that they can reach,
threatening the survival of young trees. An alleyway
with electric fencing on either side of seedling rows will
provide protection. You can buy plastic tubes that fit
around each sapling and guard the young tree from
grazing and wind. New tube designs with ventilating
holes to allow for air circulation prevent the increased
pest and disease problems encountered with earlier
designs.
Information on all types of agroforestry practices
is available in the ATTRA publication Agroforestry
Overview.
Many trees and shrubs produce seeds, leaves, or nuts
that supplement existing forages and provide valuable
feed during certain times of the year. Because trees
and shrubs are perennials with long life expectancies,
few annual costs are associated with their continued
productivity. Fodder trees – such as locusts, willows,
some poplars, leucaena, and tagaste – have potential
for either seasonal or year-round browsing. In some cases, seasonal cutting back to the trunk will produce
tender shoots that are more palatable and easily accessible
to the animals that browse them directly, but if
animals have continuous access, they may exhaust
root reserves and kill the trees. In some regions, tree
fodder is considered an emergency feed for unusually
dry seasons.
Like forage legumes, leguminous trees such as black
locust and honey locust fix nitrogen. Rhizobial bacteria
live closely with their roots, converting nitrogen from
the air into a form that the trees can use. The nitrogen
is used by the tree, but when the leaves die, they add to
the total nitrogen in the pasture system.
Traditional beliefs hold that animals will select a diet
according to their needs, if they have access to a wide
variety of plants, including shrubs and trees in the pasture
or hedgerow. When appropriate species are available,
livestock may select them to self-medicate for their
health problems. Cindy Engel in Wild Health: How Animals
Keep Themselves Well and What We Can Learn
From Them (5) explores this idea in some detail.
Pastures: Sustainable Management
By Alice Beetz and Lee Rinehart
NCAT Agriculture Specialists
Paul Driscoll, Editor
Sherry Vogel, HTML Production
IP 284
Slot 51
Back to top |