K.D. Johnson, C.L. Rhykerd,
and J.M. Hertel,
Department of Agronomy
and K.S. Hendrix,
Department of Animal Sciences,
Cooperative Extension Service
West Lafayette, IN 47907
BENEFITS OF LEGUME-RENOVATED PASTURE
MAJOR PROBLEMS IN PASTURE RENOVATION
Table 1. Effect of Forage Species and Fertility Levels
Table 2. Effect of Forage Species and Nitrogen
STEPS TO SUCCESSFUL PASTURE RENOVATION
Table 3. Suggested Legumes and Seeding Rates
In Indiana, pastures are generally relegated to land that is
too steep and rocky for row crops. The soils lend to be shallow, low in fertility and
droughty. The dominant plant species are often Kentucky bluegrass, tall fescue and weeds.
The result of this combination of conditions is usually low yields of low quality forage.
One of the best ways to improve both forage yield and animal performance on these
low-producing grass pastures is to periodically renovate them. Pasture renovation means
"renewing" a pasture by the introduction of desired forage species into present
plant stands. It usually involves partially destroying the sod, liming and fertilizing
according to soil test, seeding a legume or legume-grass mixture, and controlling weeds.
BENEFITS OF LEGUME-RENOVATED PASTURE
Research and farmer experience show that introducing legumes into Kentucky bluegrass or
tall fescue sods produces the following benefits:
||Elimination of the need for
||Better seasonal distribution
of forage. (Legumes are more productive in mid-summer than cool-season grasses.)
||Increased forage protein
content and quality.
||Improved forage digestibility
||Higher mineral concentrations
(especially calcium and magnesium), which help prevent animal health problems.
performance, such as daily gain, milk and wool production.
||Improved beef breeding
performance. (Legumes have been shown to reduce sheep breeding performance because of
Pasture renovation experiments in Ohio and Indiana illustrate the degree of improvement
from the introduction of legumes into low-producing grass sods. An Ohio State University
study (Table 1) revealed significant increases in cow-calf carrying capacity by renovating
a permanent bluegrass pasture. Some improvement was made simply by adding a better forage
grass. Further improvement was achieved by increasing soil fertility. However, the
greatest improvement resulted from growing either a mixture of alfalfa and orchardgrass or
a well-fertilized orchardgrass, both of which tripled animal carrying capacity as compared
to the unfertilized bluegrass pasture.
A recent Purdue University experiment (Table 2) further supports two of the Ohio
findings, suggesting they be carefully considered when making pasture renovation
decisions. One is that some grass species are better than others as pasture for cow-calf
herds. (Compare the daily gains and conception rates for herds on orchardgrass vs. tall
fescue receiving the same amount of nitrogen.) The second finding is that seeding a legume
into a tall fescue pasture gives better cow-calf production results than merely
fertilizing the tall fescue pasture with nitrogen and gives similar results to
N-fertilized orchardgrass. (Again in Table 2, compare animal performance on the tall
fescue-clover mixture vs. tall fescue alone receiving N fertilizer.
Pasture renovation needs to be done on a regular basis. The reason is that legumes, as
compared to grasses, tend to be short-lived in a pasture. In fact, they will disappear
rather quickly in the face of such "adversities" as lime, phosphorus and
potassium deficiency, disease and insect damage, overgrazing, drought, or grass and weed
Table 1. Effect of Forage Species and Fertility Levels on
Pasture Grazing Days and Carrying Capacity, Ohio State University.
Forage Soil grazing Acres per
species fertility days cow/calf
Bluegrass Low 59 3.13
Bluegrass Low 89 2.08
Bluegrass Moderate + 106 1.74
Orchardgrass 50 lb N
Bluegrass Good + 184 1.00
Orchardgrass 130 lb N
0rchardgrass Moderate 189 0.97
Table 2. Effect of Forage Species and Nitrogen Fertilization on
Conception Rate and Daily Gain of Cows and Calves on Pasture, Purdue University.
Lb. daily gain
Forage N fertilizer --------------- Conception
species treatment Calves Cows rate
Orchardgrass 100 lb 1.8 0.8 90%
Tall fescue 100 lb 1.2 0.02 71%
Red clover None 1.8 0.6 92%
Two problems associated with introducing a legume into pasture are the possibility of
bloat and the difficulty in getting the legume established. Potential bloat problems can
be minimized by seeding non-bloat species (birdsfoot trefoil or lespedeza), by introducing
the animals slowly to legume-containing pasture, by feeding hay before turning animals
into legume-containing pasture, or by supplement-feeding poloxalene (the active ingredient
in "Bloat Guard").
The chances of getting a seeded legume successfully established in an existing sod
depends on the farmer's ability to meet these two requirements:
* The existing vegetation must be sufficiently suppressed to permit the legume seed to
germinate and emerge. This is accomplished either by tillage or by application of a
"knockdown" herbicide in combination with overgrazing prior to seeding. If
tillage or herbicide application cannot be made, the sod still should be overgrazed.
* Management after emergence of the legume must favor the legume if a mixture is to be
To fulfill the above requirements for establishing and maintaining a good legume stand,
the following steps are suggested:
1. Overgrazing and soil testing. Livestock should be allowed to overgraze the
pasture in the fall so that tillage is more effective at tearing the sod. Even if tillage
is not clone, the grass should he overgrazed so the mulch will not interfere with legume
establishment. The soil should be tested, then limed and fertilized according to test
results, preferably before tillage. Do not apply nitrogen since that will only promote
grass growth and retard legume establishment.
2. Disturbing or suppressing the sod. If erosion is not a hazard, disk or
field-cultivate to disturb the grass sod. (Renovation is more successful if tillage can be
clone in the late fall.) To minimize soil loss, do not overwork the seedbed. The sod
should be disturbed 50-70 percent if seeding clovers and 80-90 percent if seeding alfalfa
and birdsfoot trefoil. It is not necessary to reseed the grass, since the undisturbed
tillers will begin to grow the following spring.
On sloping land with highly erosive soils where tillage is not practical, the grass
stand can be "knocked back" with Paraquat, which has been cleared for such use.
However, the grass must be actively growing for Paraquat to be effective. Therefore, wait
until the grass has "greened up" to apply it.
3. Seeding the legumes. Frost-seeding inoculated legumes in the late winter has
provided good results in tillage-disturbed and undisturbed sod.
On Paraquat-treated sod, legumes can be seeded immediately after application. Seeding
is best accomplished after Paraquat treatment with a no-till drill, because it places the
seed in direct contact with the soil at the proper seeding depth (1/4 - 3/8 inch).
Overseeding Paraquat-treated sod is not effective because there is no frost action to
provide seed-soil contact that late in the season.
Table 3 lists the legume species, alone or in mixture, considered best for renovation
and their proper seeding rates. Alfalfa should not be used on soils that heave severely.
Lespedeza should not be sown in the northern half of Indiana. Birdsfoot trefoil
complements bluegrass pastures very well. Always select "improved" varieties.
4. Grazing newly legume-seeded pasture. In the spring once the grass is growing
and the ground has dried out enough to support livestock, graze the pasture until the
animals start to defoliate the legume seedlings. Then remove the livestock and rest the
pasture 8-10 weeks for the legumes to establish.
Table 3. Suggested Legumes and Seeding Rates for Renovating
Seed Lb. per acre
mixture Species seeding rate
1 Red Clover 8-10
Ladino clover 0.5-1
2 Alfalfa 10-12
Red clover 2- 4
3 Annual lespedeza 20-25
4 Red clover 6- 7
Ladino clover 0.5-1
Annual lespedeza 8-10
5 Birdsfoot trefoil 5
* Assumes high quality seed (90+% germination and 99+% pure)
5. Grazing established grass-legume pastures. Rotationally graze from spring to
fall this favors the legumes. To rotate, use several fields or divide a field into
paddocks with an electric fence. Adjust the stocking rate per field or paddock to
defoliate grass-legumes within a 7 - to 10-day period. Do not overgraze, and plan on
providing plenty of recovery time (usually from 21 to 35 clays, depending on time of
season and rate of regrowth). A 7-day grazing period and 28-day rest period will require
five fields or paddocks. A 10-day grazing period will require four fields.
One suggested grazing system is to: (a) harvest one or two hay crops in the spring and
summer, (b) allow 30-35 clays for recovery, (c) graze off in 7-10 days, (d) repeat the
resting-grazing cycle, and (e) allow 4 weeks of plant recovery before the first killing
6. Fertilizing. Topdress annually with phosphorus and potassium according to
7. Re-renovating. Plan on it when the legume disappears and the fescue or
bluegrass takes over.
AY-251 RR 2/92
Cooperative Extension work in Agriculture and Home Economics, State of Indiana,
Purdue University and U.S. Department of Agriculture cooperating: H.A. Wadsworth,
Director, West Lafayette, IN. Issued in furtherance of the acts of May 8 and June 30,
1914. The Cooperative Extension Service of Purdue University is an equal opportunity/equal