Harvesting alfalfa by grazing with livestock can be profitable for
experienced producers who utilize critical management practices. Producers
who are unfamiliar with managing livestock on lush forages should be
extremely careful and attempt grazing only on a small scale. Without proper
management, losses of livestock due to bloat can become quite costly.
Grazing has been reported to shorten the life of alfalfa stands, compared to
harvesting alfalfa for hay; however, if proper management practices are
followed, grazing effects on stand life are negligible.
For most alfalfa production situations, grazing during fall and winter
has more advantages than disadvantages. Spring grazing, however, is
difficult to manage for most producers, and successful summer grazing can be
considered intermediate from the standpoint of both positive and negative
aspects. Considerations to be taken into account when determining whether to
graze alfalfa follow.
Back to Grazing Alfalfa
Positive
Aspects
Some reasons to consider grazing alfalfa include:
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In spring, harvesting alfalfa by grazing can reduce weather-related
problems associated with normal timing of first harvest (late April
and early May). First-cutting hay yields are normally high,
resulting in large windrows. The hay is difficult to dry and
frequently requires 5-10 days without rain. As a result, most
first-cutting hay is damaged by rain before it is dry enough to
bale. |
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Alfalfa grazed in late March or early April is not ready to
harvest again before May 15 to 20 under normal conditions. By that
time, the frequency of rainfall is likely to be lower, and
temperatures are higher; thus, hay dries more rapidly with less
chance of rain before baling. Furthermore, the volume of hay is
reduced and should be easier to cure. |
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In spring, producers often need high-quality forage for
stocker cattle that were maintained on wheat pasture during winter.
Alfalfa can be used for this purpose, and average daily gains may be
comparable to those on wheat (frequently from 1.7 to 2.3 pounds per
day). |
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Grazing alfalfa infested with weevils and/or aphids during spring
can reduce the habitat available to the insects and results in
mortality of large numbers of insects, greatly reducing the need for
insecticide application. The highest mortality of alfalfa weevil and
aphids results with spring grazing. |
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Summer grazing is especially attractive when hay yields are
low during July and August due to dry conditions. Summer grazing
also is a good way to utilize thinning stands infested with grasses
and other weeds. Normally, forage nutritive value of these weeds is
good, and grass in alfalfa reduces the chances of bloat. |
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In late fall and winter, grazing is the most effective and
economical means of utilizing late-season forage. Late fall and
winter grazing is a good means of reducing alfalfa weevil
infestations by effectively reducing sites for weevils to lay eggs.
Additionally, livestock will consume existing eggs in alfalfa stems. |
Back to Grazing Alfalfa
Negative
Aspects
Grazing alfalfa during active growth is a challenge, and there are
concerns associated with this practice. Therefore, few producers in Oklahoma
routinely graze actively growing alfalfa. Some of the major concerns
include:
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Bloat: Fear of losing animals to bloat is the
most frequently cited reason for not grazing alfalfa. Lush alfalfa
growth in early spring is the most likely period for bloat to occur.
All alfalfa varieties can cause bloat, including those called
"grazing alfalfa." Careful management of animals can
minimize bloat problems. Bloat is less prevalent during the
summer; nevertheless, precautions should be taken to guard against
it. Accepted practices to lessen the occurrence of bloat are listed
in Figure 7-1.
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Inconsistent animal performance: Weight gain
depends on many factors including animal type, previous nutrition,
forage availability and quality, and environmental stress
(heat, cold, mud). Management of livestock and the grazing system
has a tremendous impact on many of these factors. For example,
animals forced to consume low-quality, mature alfalfa frequently
gain less than one pound per day. Intensive management and favorable
weather conditions are required to maintain maximum animal
performance. |
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Stand loss: Removing animals when the soil is
saturated to the point where animals leave deep tracks can minimize
stand loss problems (another reason for not grazing alfalfa).
Rotational stocking or mob grazing (high stocking density for a day
or two) to remove forage quickly normally results in no stand loss
problems as long as adequate rest periods between harvests are
provided. |
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Grass and weed infestation: Grazing alfalfa in
early April can increase the amount of cool-season grass in the
second alfalfa harvest. Vigorous alfalfa often smothers grasses
during April. However, removing alfalfa allows light to reach the
grasses that are then able to compete with alfalfa and produce seed.
If weed-free hay is the target for second harvest, then weeds should
be controlled with a selective herbicide before grazing. |
Back to Grazing Alfalfa
Grazing
Practices during the Growing Season
There is no single acceptable practice for grazing alfalfa. Both
continuous and rotational stocking is possible and can be successful if
managed properly.
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To reduce the chances of
damaging stands and to maintain stocker gains between 1.5-2.0 pounds
per day, some type of controlled or rotational stocking should
be practiced. There is no set rule on the number and size of paddocks;
however, paddocks should be small enough for animals to complete grazing in less
than a week. Ideally, allow 4-5 weeks for recovery
before another round of rotational grazing begins. A good program would be
to divide the field into eight paddocks and graze each area four
days. To prevent damage to the stand, cattle should be removed when fields
become muddy. |
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Rotational stocking
(grazing less than five days followed by regrowth for at least 3 weeks)
will result in high forage production and animal gains. In general,
good hay-type varieties respond in the same way to rotational
stocking as to cutting for hay. |
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Rotational stocking can
minimize the ill effects associated with thinning alfalfa stands
because of grazing. Animals should not be left on any particular
part of the field longer than one week. If animals remain on the
field longer, much of the available forage is lost by trampling, and
new regrowth will be eaten. Rotational stocking should alleviate
both of these problems. The best combination of days of grazing and
regrowth changes during the growing season because alfalfa grows at
different rates. It matures most rapidly when temperatures are high
( 90o F and higher) and there is adequate moisture. |
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Continuous stocking
of hay-type alfalfa (and probably grazing types) should be managed
so alfalfa is not grazed shorter than 6 inches. This means stocking
rates are adjusted several times during the growing season by
removing and introducing animals as dictated by alfalfa growth rate. |
Research at the Grazinglands Research Laboratory at El Reno,
OK, has
shown continuous stocking is a good method for grazing stockers, resulting
in gains exceeding two pounds per day using a well-adapted hay-type alfalfa
variety. However, many producers find this system difficult because of the
need to divide the herd and adjust stocking rates with each change in
growing conditions.
Back to Grazing Alfalfa
Economics
of Grazing during the Growing Season
A strong argument for grazing alfalfa is the reduced cost
of harvesting. Stocker gains of 1.5-2 pounds per day are attainable. Alfalfa
yields of 0.75 ton per acre (grazable) can be assumed in early to mid-April.
Assuming stockers consume 15 pounds per head per day, 100 stocker-days per
acre are present
in typical alfalfa stands. Allowing one week to consume available forage,
approximately 14 head per acre would be used, gaining 14 pounds per acre on average. At
$.30 per pound of gain, almost $59 per acre could be earned during a
one-week grazing
period. Cost of grazing would include fencing, labor, poloxalene, and dry hay for bloat
control.
Economic return is also a reason for interest in summer
grazing. Cutting, raking, and baling cost approximately $21 per acre per
cutting. If
weed-free hay sells for $80 per ton and grazable summer yields are 0.5 ton
per acre,
only $14 per acre would remain after harvest and hauling costs. With grazing as
an alternative, assuming one pound of gain for each ten pounds of forage, 100
pounds of
beef gain could be achieved. One hundred pounds of gain would be worth $30
per acre at current rental rates ($.30 per pound gain). If a producer owns the
cattle, a higher return could be achieved.
In late summer, instead of making hay, a better option
may be to graze droughty alfalfa. Grazing is the least expensive way to
harvest alfalfa. When alfalfa is droughty in the summer, bloat problems are
easily controlled. During late summer, when alfalfa stops growing, mob
grazing can be a very good way to harvest.
Stockers can gain between 1.5-2 pounds per day on this type
of forage. Considering 600 pounds per acre of alfalfa are present and stockers consuming
15 pounds per day, there are about 40 stocker-days of forage per acre. Stocking at
four stockers per acre, the field can be cleaned in 10 days. If the cattle gained
1.76 pounds per day worth $0.30 per pound of gain, the forage is worth about
$21 per acre, about
the same as the value of hay, without harvesting equipment costs. As with
spring grazing, cost of grazing includes fencing, poloxalene, and labor.
Back to Grazing Alfalfa
Late
Fall and Winter Grazing
Mob grazing alfalfa after the first killing frost (20°F)
in November or December is likely to be a better option than trying to make
hay. Making hay during this time is difficult because of poor drying
conditions-- i.e., low temperature, high relative humidity, and reduced solar
radiation.
Another consideration is the value of the hay. The value of hay would be
about $40 per acre (gross), assuming 0.5 ton per acre (grazable)
at $80 per ton. When harvesting cost is approximately $21 per acre, only $19
per acre
remains to cover costs of hauling and storage. This optimistically assumes
the hay is baled before it is damaged by precipitation. Grazing would cost
much less than haying, assuming no loss due to bloat. Using a
grazing value of $60 per ton, the 0.5 tons per acre yield would be valued at
$30 per acre. Expenses of grazing include bloat prevention, fencing, and labor.
Grazing after frost also helps control
insects. During
grazing, sites for alfalfa weevil eggs are removed and eggs in stems are
consumed, reducing the number of eggs available for hatching the following
spring. Grazing on dry fields after a hard freeze will also result in some
control of broadleaf weeds. Further, the hoof action of the livestock will
cause uprooting of small weeds. See Chapter 2, "Insect
Management - Alfalfa Weevil" for details.
Back to Grazing Alfalfa
Pasturing
Dairy Cattle
Recently, some dairy producers have taken another look at
grazing for their lactating herd as a way to make more effective use of
their land and reduce operating costs. The key to success in grazing alfalfa
with dairy cattle is to manage the fields in a grazing system with adequate
periods of rest to allow for proper regrowth. The following are suggestions
producers should follow to reduce potential problems and provide effective
grazing.
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To reduce the potential of bloat during spring
grazing, cows should be fed before being allowed access to pasture.
An additional precaution may be to limit access to the pasture. Over
a period of one to two weeks, cows may be allowed access for increasing
intervals until animals are on pasture continuously. Once adapted,
bloat usually does not occur unless cows are forced to graze
pastures too closely and are hungry when moved to the next paddock. |
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Move cows to new paddocks frequently in order to
ensure high-quality forage is available daily. Low-producing cows,
heifers, and dry cows may be allowed to graze after the high-producing cows to clean up pastures and
make use of the lower-quality
forage. |
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Grazing may provide 40 to
50 percent of total dry matter intake. The remainder of intake can
be used to balance the ration. |
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High producing cows may
need some source of rumen-undegradable protein (e.g., blood meal, fish meal, etc.) to meet protein and amino acid requirements for high
production. |
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Feeding high-starch feeds such as corn will help
"capture" the soluble protein portion of alfalfa and
increase rumen microbial protein production. |
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Feeds such as soybean
hulls, whole cottonseed, wheat midds, or corn gluten feed may also
be incorporated into the grain mix to provide appropriate levels of
highly digestible carbohydrate while providing a source of fiber.
Additionally, some hay also may need to be fed to maintain fiber
levels in the ration and to prevent digestive upsets and milk fat depression. |
Pasture based dairy operations
can achieve excellent production levels while controlling input costs.
However, close attention to detail, proper supplementation, and use of
rotational stocking are needed in order to realize maximum benefit from an
alfalfa grazing system.
Back to Grazing Alfalfa
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