Farmers have long known that livestock
pastured on grass and clover gain weight faster than those fed only grass.
Clover mixed with grass in pastures reduces the need for application of
nitrogen, thus saving farmers time and money. Many Extension publications are
written on legume production and benefits to livestock. However, there are
also many benefits to wildlife from growing legumes. NOTE:
Many University of Kentucky Cooperative Extension Service publications are
referenced in this article as (AGR - #). For more details or copies of these
publications contact your local Extension office.
What are legumes?
Legumes are a group of plants
including alfalfa, clovers, lespedezas, beans and peas that are able to
convert or "fix" atmospheric nitrogen into a form usable by plants
and animals. Once "fixed", the nitrogen found in legumes becomes an
essential building block for various proteins which plants and animals
require. Legumes are able to fix and store nitrogen in small nodules on the
roots because of bacteria called Rhizobium. These bacteria located in the
roots of the plant do not harm the plant and must be present in the soil for
legumes to convert nitrogen.
Benefits of Legumes
Build soil nutrients
The amount of nitrogen fixed and stored by legumes may
range from 50 – 200 pounds per acre per year. The stored nitrogen enriches
the soil and feeds all plants in the area (legumes, grasses, shrubs and trees)
whose roots come in contact with that nitrogen. These plants are valuable as
wildlife food and cover.
Provide excellent forage
Soils low in nitrogen generally are less productive in
the amount and diversity of plants that serve as wildlife food. Nitrogen rich
soils produce lush vegetation that serves as a food source either in the form
of the plants’ leaves and stems or the seed and fruit produced. Legumes,
being self-fed by their nitrogen-fixing ability, are high in protein. All
growing animals require high levels of protein in their diet to build body
tissue. Young, growing animals and females during egg laying or milk
production periods desperately need high levels of protein. For example,
researchers have determined that nursing white-tailed deer require a diet that
contains 14-16% crude protein, growing bucks need 12-14% and quail chicks
require foods averaging 28% crude protein during the first three weeks of
While legumes are capable of providing high levels of
protein, none are able to provide the level needed by hatchling grouse, quail
and turkeys. Their need for very high protein foods is met by eating insects.
Bodies of many insects are 40 to 50 percent protein, some even more. Birds and
many mammals eat great numbers of insects, especially in late spring and early
summer months. Without an abundance of this nitrogen rich source of food,
young wildlife may die. The connection between legumes and insect populations
is simple. Animals, such as insects, get the protein they need from eating
plants that are high in nitrogen. Legumes are among the most nitrogen-rich
plants insects can eat. Insects are attracted to a diversity of forbs
(broadleaf, herbaceous plants) that are common in Kentucky soils enriched with
the nitrogen provided by legumes. As a general rule, insect populations are
higher in areas with legumes and other forbs compared to pure grass stands.
Turkey hens prefer to nest within 100
yards of good cover and fields containing high insect populations to which
they can take their broods immediately after hatching. Survival of young
grouse, turkey, quail and some songbird chicks is critically linked to finding
a safe place to feed on an abundance of insects. Cool season legumes such as
clover and alfalfa patches located near good nesting cover serve this purpose.
Provide good cover
Another benefit of legumes is the type of cover they
provide. The growth form of most legumes is beneficial to small, ground
feeding wildlife because legumes do not form a thick mat of ground level
vegetation like some grasses that become an obstacle to the animals as they
travel or attempt to locate seeds and insects. Legumes such as clover are like
miniature forests, having stems with few leaves near the ground and most
leaves at the top forming a closed canopy. This condition is generally open
enough at ground level to allow quail chicks and turkey poults to easily walk
through while feeding on insects. Turkey hens move broods into areas that
provide suitable feeding cover but not so dense that they become lost from the
hens. If the legumes are nearly a foot tall, the young birds may feed in them
and be almost invisible to avian predators such as hawks. Legume fields with
little or no grass also make it easier for very young birds and mammals to
travel through without becoming wet from dew or rain. Cool, wet springs are
often very detrimental to the success of ground nesting and feeding wildlife
because the young animals are sometimes not able to locate the food they need
without exposing themselves to the hazard of getting wet and cold. The
availability of pure stands of legumes provides young wildlife with the
benefits of excellent forage and insect numbers in a place open enough to
allow ease of movement without constant contact with dense, wet vegetation.
Finding food is a constant need for
wildlife and one that exposes them to the dangers of adverse weather and
predators. The faster wildlife can feed and be filled, the sooner they may
return to more secure areas such as cover thickets*, thus increasing the
individual’s likelihood of survival.
Types of Legumes
Legumes may be classified many different ways.
One way is to separate the legumes as either annuals (must be seeded each
year) or perennials (productive for several years without the need for
replanting). While many different types of legumes are useful to wildlife,
just a few of the most commonly used ones are mentioned below.
Annual lespedezas (Korean and Kobe): Both
Korean and Kobe lespedeza do most of their growing during the warm summer
months. They are fairly tolerant to drought and low soil pH and fertility.
Lespedezas were introduced into the U.S. in the early 1900’s and by the 1940’s
were planted on large acreages. However, lespedeza use dropped sharply when
more productive legume species and fertilizers became widely available. Korean
lespedeza is less competitive with companion grasses than Kobe. Both do very
well in river bottoms that overflow in the winter. Both also are killed by
frost and provide little winter cover. Kobe is later seeding and early frost
threatens seed production. The seed of both is highly prized as a food for
Partridge Pea: A native, annual warm season legume that
is tolerant to many soil conditions. Provides excellent seed within pea pods.
Responds well to disking every third year to ensure proper reseeding.
Soybeans: A common warm season agricultural crop favored
by wildlife for forage and seed. Some varieties are for forage production and
continue stem and leaf production after being grazed. Other types are for seed
production and may not produce seed if browsed by wildlife. Soybeans are
excellent wildlife food in summer and fall. However, they lose their leaves at
frost and the pods open, dropping seeds on the ground. Seeds do not persist
long on the ground making soybeans a poor choice as a winter wildlife food
source. Generally, soybeans favor well-drained, fertile soils with pH levels
from 5.8 to 7.0.
Cowpeas: A warm season annual vine that produces peas
favored by quail and stems and leaves favored by deer, rabbits and livestock.
Cowpeas are beneficial for their soil improvement ability and are often
planted with corn or milo as support for vines. They tolerate a wide range of
soil pH conditions from 5.5 to 7.0.
Alfalfa: Many new varieties are now available
including grazing tolerant types. Alfalfa produces one of the highest crude
protein levels and greatest yields of any legume. It is generally considered
the most difficult to establish, but once established is a very tough and
persistent legume. Success of the stand will depend upon a well-drained soil,
attention to detail during establishment and proper maintenance. Alfalfa
requires high levels of phosphorus and potassium and soil pH in the 6.6 to 7.2
range. Its deep roots make it a very drought resistant, cool season legume.
Birdsfoot Trefoil: A native cool season legume
that is often slow to get established. It has very high palatability and is
fairly drought resistant. It requires medium soil fertility and pH of 6.0 to
Ladino white clover: This type of large, white
clover grows 12 to 15 inches in ideal conditions during cool season periods
and has been very popular among cattle producers for years. It has also become
a main planting for deer herd managers in the southern United States. All
insect eating wildlife benefit from field plantings of Ladino clover in pure
stands or mixed with grasses. Ladino is poorly adapted to drought conditions
though it is somewhat tolerant of poorly drained soils and some shading. It
requires fertile soils with a pH of 6.0 to 6.5.
Regal clover: Another type of white clover that
is very similar to Ladino but produces especially well in late summer.
White Dutch clover: The smallest of white clovers in
height of plant and size of flowers. This common clover is often found in
lawns and is poorly tolerant to drought. It is extremely low yielding compared
to Ladino or Regal white clovers but may be more successfully established in
shaded conditions. White Dutch is well adapted to poorly drained, medium
fertility soils having pH values of 6.0 to 6.5.
Red clover: Excellent for livestock pasture renovation.
It does fairly well in droughty soils and is somewhat adapted to poorly
drained soils. Red clovers generally require medium fertility and pH of 6.2 to
Alsike clover: Similar to red clover, but the blossom is
pale-pink to white rather than purplish-red. Alsike grows on ground too wet or
too acidic for red clover. It does fair in drought conditions, requires medium
fertility and a pH of 6.0 to 6.5.
Most agricultural plants do best with
soil pH levels near or slightly below 7. Kentucky soils are generally acidic
(between 5.5 and 6.5) and lime is commonly used to correct that condition.
Soil test values indicating moderate levels of phosphate are 30 - 60 and
potassium are 165 - 250. Though a few legumes may survive below those moderate
levels, most are productive only at higher levels of soil phosphate and
potassium. Only by soil testing can you know the pH and fertility condition of
the soil and be able to make the necessary corrections by adding soil
Planting Sites for Legumes
Understanding the basic requirements of legumes
will help determine where planting will be most successful. The following is a
list of 6 factors to consider before picking a location for your legume
Soil pH and Fertility
In general, legumes require moderately fertile
soils with pH levels between 6.0 and 7.0. Alfalfa is especially sensitive to
soil acidity and needs a pH level near 6.7. Alfalfa also requires high levels
of phosphate (above 60) and potassium (above 250) in the soil. At the other
extreme, Korean Lespedeza has excellent tolerance to acidic soils and low
levels of phosphate (less than 30) and potassium (less than 165). Generally,
the soil pH and fertility requirements for various types of red and white
clovers fall somewhere between those of alfalfa and Korean Lespedeza. Soils
that have been recently used for planting crops such as tobacco, corn or
soybeans are likely to have pH and fertility levels near those needed for
legumes. These may be good locations for successful production of legumes.
Moisture requirements of the various legumes
differ greatly. Though all do well in moist, well-drained soils, because of
its deep roots alfalfa will do well during periods of drought. White and red
clovers are relatively shallow rooted and are only rated as fair in droughty
soil conditions. In wet areas, Alsike clover is rated most tolerant. The
difference in soil moisture conditions from ridge tops to creek bottoms and
north facing to south facing slopes can be dramatic. If the choice of places
to plant legumes is limited, select a type of legume best suited for that
Few legumes do well in shade. Those that are
somewhat tolerant of low sunlight conditions include Ladino and White Dutch
clover. Try these species on narrow woodland trails or any other area where
tree cover prevents sunlight for much of the day. Woodland edge feathering* or
"daylighting" may allow needed sunlight to reach trails and
Legumes do not compete well with other plants.
Planting locations should be free of dense stands of grass and woody plants
such as trees, shrubs, vines and briars. In some cases it may be wise to delay
planting for a season until competing vegetation is controlled. Any
pre-existing vegetation may rob legume seedlings of necessary nutrients,
moisture and sunlight. To eliminate the site of unwanted vegetation, it may be
necessary to apply herbicide or plow and disk the soil. Such activity, plus
the eventual need to be able to mow the area, requires the land to be level or
only moderately sloped.
Cropland Chemical Residues
It is important to note that alfalfa and other legumes
are sensitive to low concentrations of herbicides such as those containing
atrazine (e.g., Aatrexâ) and simazine (e.g., Princepâ) (AGR – 140 and
148). Also, if sowing legumes in areas where native warm season grasses* have
been recently established, be sure to determine if the herbicide called
Plateau was used. If the area you want to plant legumes has a cropping history
that includes the use of any herbicide, be sure to contact your local
Extension office for information on the effects of previous herbicide use.
A final consideration for where legumes should be
planted is positioning the legumes close to cover. Since many wildlife species
are attracted to legumes as a source of food, the landowner should attempt to
provide as safe a feeding opportunity as possible. Position legume plots in
strips next to tall grass, shrubs or woodlands so animals may flee into that
protective cover when pursued by predators. Clover or alfalfa hay fields
located in the middle of open pastureland are especially attractive, but
dangerous, to small wildlife who, when feeding, become exposed to predators.
Provide cover thickets* in large fields as places for wildlife to escape
Legumes Best Suited for Certain
Shaded Area White Dutch Clover
||Korean or Kobe
Alfalfa, Birdsfoot Trefoil
Establishment of Legumes
Establishment of legumes may be broken into two phases:
Pre-planting and Planting.
After deciding where to plant and picking the best type
of legume to plant to meet your objectives and existing conditions, there are
three other things that need to be done before planting.
Soil pH and Fertility Improvements: There is a very
important correlation between soil pH and fertility. Soil pH levels influence
the availability of nutrients to plants. For example, the availability of
phosphorus is reduced in low pH soils because it binds with iron and aluminum
at pH levels less than 5.5. Soil pH may also be too high or too basic. If the
pH is too high, phosphorus reacts with calcium reducing the amount available
to the plants (AGR – 19). As a result, plants in soils having adequate
levels of phosphorus and potassium may not be able to utilize those nutrients
if the pH level is too high or too low.
Phosphorus is critical for establishment of legumes.
Inadequate levels of this element will result in poor legume production.
Potassium is also necessary and levels must be monitored since high yields of
legumes remove large amounts of this element from the soil.
The only way to know the pH and fertility of the soil is
to have it tested. Test results will tell you exactly how much lime and
fertilizer is needed. If results show a need for improvements, you must decide
if you have the ability to make those improvements. Can you get to the field
with the necessary lime and fertilizer? Can you afford to purchase those
items? If the answer to either one of those questions is "no", then
you may select a legume with less strict requirements of pH and fertility or
wait until you do have the ability to make the necessary improvements.
If lime is needed, it is best to apply it at least 6
months ahead of legume seeding so it has time to react with the soil.
Otherwise, apply lime as soon before seeding as possible (AGR – 116). The
rate of lime recommended in soil tests is for the use of ag-lime or quarry
lime. If you have little or no advance time to apply lime before sowing
legumes, you may apply half of the recommended lime rate as finely ground or
"quick lime" to the field at planting time. This type of lime will
not persist long in the soil but reacts quickly. It is available at most farm
supply stores and is often sold in 50 pound bags. If quick lime is used, be
sure to also spread the more coarse ag-lime at planting time or as soon
afterward as possible at the full rate recommended by the soil test results.
The addition of phosphorus and potassium based on the
recommendation from the soil test may be made at any time prior to planting
since those chemicals are relatively stable in the soil but react quickly. Do
not apply nitrogen to legume plantings! This is very important since
nitrogen will feed unwanted plants that will compete against the legumes.
Example: If you want to sow a Ľ
acre field to clover next week, but the soil test results indicate you need 2
tons of ag-lime per acre (1000 lbs. per Ľ acre), apply one half of that rate
(500 lbs.) as quick lime and 1000 lbs. as ag-lime to get the necessary
immediate results. The alternative is to apply the 1000 lbs. of ag-lime and
wait 6 months for the lime react with the soil before planting the seed.
Weed Control: Mowing, plowing and disking a field is a
great start to weed control, but tilling the soil at the wrong time may cause
avoidable weed problems. The general belief is that tillage stirs buried weed
seeds up to the surface allowing them to germinate. The decision to plant
legumes in the spring or in the fall may depend on the types of weeds present.
If you have an abundance of summer growing weeds (crabgrass, ragweed, foxtail,
or lambsquarters) where you intend to plant legumes, you should attempt sowing
in the fall. Spring plantings are usually more successful where winter weeds
(chickweed, henbit, and yellow rocket) are a problem.
Some attention must also be paid to the effect other
plants have on the desired legumes. One common grass called quackgrass has
been found to be allelophathic, meaning it releases chemicals that may
seriously reduce growth or the nitrogen-fixing ability of alfalfa and other
legumes. On the positive side, winter wheat or rye plantings are often used as
companion crops with legumes because they release chemicals that suppress the
development of weeds but do not harm legumes.
Though timing and planting technique will help reduce
the impact of different types of weeds, additional success will result from
herbicide treatments before or even after your plantings have been made. Some
herbicides that may be used to kill weeds before planting legumes include
Balanâ and Roundupâ. In established legume stands, Poastâ or Pursuitâ may
be used. Always follow label recommendations when using any herbicide. For
details about the use of these and other herbicides refer to AGR – 148.
Seedbed Preparation: The purpose of a seedbed is to
eliminate as much existing vegetation as possible and provide a place for good
seed to soil contact. Depending on the type of equipment available and
conditions of the soil, this may be accomplished by repeated disking or it may
require plowing and then disking.
Clover and alfalfa seeds are very small and only need to
be planted to a depth of 1/8 inch. The seedbed should be very smooth for
broadcasting these seeds. When planting larger seed, such as cowpeas and
soybeans, it is less critical to prepare a finely disked seedbed since these
larger seeds are more vigorous and are able to survive a rougher textured
It is possible to disk a seedbed too much. Over-disking
creates a seedbed that is too loose to hold the moisture necessary for seed
germination. Allowing the freshly disked soil to settle for a couple of weeks
before sowing seed or compacting the soil with a cultipacker before planting
will improve this condition.
If at all possible, do not disk seedbeds while the soil
is wet. This will result in clumpy soil and require another disking once the
soil has dried in order to get a smooth result.
is an effect plants have on other plants through the release of chemicals that
eliminate or reduce competition from other plants for nutrients, moisture and
sunlight. Alfalfa is the most studied species in regards to allelopathy.
Alfalfa releases chemicals in the soil that are toxic to its own seedlings.
Older stands of alfalfa tend to inhibit new alfalfa seedlings which prevents
the replanting of alfalfa into an existing stand. However, one year without
alfalfa is sufficient to nullify its detrimental effects. Annual rye releases
a chemical through its roots that prevents certain seeds from germinating.
Weeds that may be affected include: green foxtail, pigweed, ragweed,
lambsquarters, common purslane and eastern black nightshade.
Be sure to purchase quality, weed-free seed. It is
important also to make sure the legume seeds are inoculated (AGR – 90). Many
of the bacteria necessary for legumes to fix nitrogen may be present in the
soil. However, not all are equally effective in fixing nitrogen. To ensure the
right bacteria is present for the type of legume you plant, purchase the
correct bacteria inoculant at the time you buy your seed. Legume inoculant is
inexpensive and may be critical to the success of your planting. Bags of
inoculant are dated. Do not use after expiration date.
Types of Plantings
Pure Stands of Legumes: One type of legume or a mix of
several types of legumes in a plot with no grasses can provide the type of
cover that allows ease of movement for feeding preferred by many small
Legume/Grass Mixtures: These provide more year-round
forage for wildlife and livestock than pure stands of legumes and make good
Companion Crop: Mixing legumes with annual wheat or rye
can provide weed control benefits and quick fall and winter forage while
legumes mature. These annuals also provide excellent seed as food for wildlife
in early summer.
Broadcasting: All legumes may be broadcast sown. Because
broadcasting is an effective method that requires little or no special
equipment, it is the planting technique most commonly used for most legumes.
For small legume plots, a hand-operated broadcast seeder is very practical.
Electric broadcast seeders can be mounted to ATV’s, tractors and pickup
Broadcasted seed needs to be put in firm contact with
the soil. Immediately after sowing seed, cultipack or lightly disk the
seedbed. Remember, the very fine clover and alfalfa seeds can be covered too
deeply. If using a disk, do so very lightly. A six-foot section of chainlink
fence or an old bed spring may be used successfully to cover legume plantings.
Legumes may be broadcast into existing stands of grass
for pasture or hayland* renovation (AGR 26) or into annual grains* such as
winter wheat or rye. No disking is required if broadcasting legume seed into a
sparsely sown stand of wheat or rye. However, if sowing into grass, be sure to
reduce the amount of grass covering the ground by grazing or mowing the site
prior to planting. It is recommended that 40 to 60% of the grass sod be
disturbed by disking prior to broadcasting clover. More soil disturbance is
required when sowing alfalfa. Broadcasting onto snow during February or March
can be an effective seeding method; it allows the seed to be worked into the
soil by melting action and will germinate when soil temperatures are suitable.
Avoid broadcasting seed on windy days since this makes it difficult to
distribute seed evenly.
Seed Drill or Corn Planter: These implements, pulled
behind tractors, are used to plant larger legumes, such as cowpeas and
soybeans, into a prepared seedbed. These planters place and cover seeds in
regularly spaced rows in one pass.
No-Till Drill: This tractor-drawn implement requires no
seedbed preparation. To eliminate or reduce existing vegetation, herbicides
are normally applied prior to planting. With the application of herbicides and
by not plowing or disking when using a no-till planter, often less sprouting
of weeds occurs compared to the other techniques.
Recipe for a Small Legume Patch
Locate a Ľ acre open area that is in
grass or weeds and briars, but not in tree saplings. Take a soil sample to
your Extension office for testing, indicating what type of legume you plan to
sow. If the area is in tall grass or briars, mow it once or twice to get all
vegetation to ground level. Apply lime at rate determined by soil test
results. Plow and disk the plot during spring or summer. Disk again in August
or September, apply the recommended amount of phosphorus and potassium and sow
15 pounds (a rate of 1 bushel per acre) of winter wheat. Lightly disk or
cultipack immediately after seeding wheat. In February or March, on a light
snow or prior to a rain shower, broadcast 1 pound of Ladino clover seed that
has been mixed with the appropriate inoculant. The melting snow or rain will
carry the seed into the soil.
Maintenance of Legumes
Lime and Fertilizer
Some types of legumes remove significant amounts of
phosphorus and potassium from the soil. Established legume or legume and grass
fields should be soil tested at least every three years to determine pH and
It is important that legumes not be overgrown by grass
and weeds. In pasture situations, livestock grazing often keeps grass and some
weeds clipped. Deer and other animals may keep small legume fields or patches
eaten down. In either case, mowing should be done if weeds or grasses threaten
to outgrow legumes. Note: Cutting clover during hot, dry weather weakens
the plants and may result in a thinner stand the following year.
While control of weeds is important in production
pastures and haylands and proper use of herbicides is a valuable management
tool, it may not be necessary to spray weeds in wildlife legume plots. Note:
Landowners should learn to recognize and control thistles and other noxious
weeds. Contact your Extension office for more information.
Possible Uses of Legumes on
Cropland rotation: Rest corn and tobacco fields by
planting to legumes.
Cool Season* Pasture and Hayland Improvement: All cool
season pastures and hay fields with fescue grass should be converted* to
timothy and/or orchard grass and legumes. For maximum benefits to livestock
and wildlife, all fields should be renovated as needed (AGR – 26).
Native Warm Season Grass Plantings: Whether used as
pastures, haylands or wildlife cover, warm season grass* fields should include
some legumes. Legumes may be sown with the native grass seed or sown afterward
into established grass stands. A native legume such as partridge pea is a good
Firelanes: Legume plantings make excellent firelanes.
Surrounding a warm season grass field with a clover strip 30 feet wide
provides all the benefits of legumes. Similarly, planting woodland trails with
clover creates effective firelanes.
Food Plots and Woodland Openings: 1/8 acre (20 yds X 30
yds) up to Ľ acre (25 yds X 50 yds) patches of one type of legume such as
Ladino clover or a legume/orchardgrass mix should be scattered throughout the
property and close to good cover.
Woodland Trails: Sow narrow trails to Ladino, White
Dutch clover, and orchardgrass. Winter wheat or rye sown as a nurse crop helps
stabilize the soil until the grass and clover become established.
Powerline Rights-of-Way: In wooded areas, rights-of-way
planted to legumes provide excellent forage next to good cover.
Honeybees: Honeybees greatly benefit from most legume
Legumes are very valuable to many types of wildlife and
all landowners should seriously consider planting them for wildlife. A small
portion of a property put into legume plantings can make a great difference.
As little as ˝ to 1 percent of a property put into high quality wildlife
plantings, such as legumes, can increase reproduction, growth and antler
development in white-tailed deer. Legume plantings should be a basic
ingredient of every deer, turkey, grouse, rabbit, and quail management plan as
well as those with bluebirds, meadowlarks, and American kestrels in mind.
Planting Dates And Seeding
||Seeding Rates (lbs./acre)
|Annual Lespedeza (Korean
||Feb. 15 - April 1
||Feb. 15 - April 15
||May 15 - July 15
||May 15 - July 1
||March 1 - April 15
Aug. 1 - Sept. 15
||Aug. 1 - Sept. 15
|White Clover (Ladino,
White Dutch, Regal)
||Feb. 1 - April 15
Aug. 1 - Sept. 10
||Feb. 1 - April 15
Aug. 1 - Sept. 10
||Feb. 1 - Apr. 15
Aug. 1 - Sept. 10
*When planting these with grasses reduce seeding rate by
50% of the average rate.
**Cool season grasses such as orchard grass and timothy
are sometimes more successful if planted in the fall. Many legumes do well if
planted in the spring. When planting grass/legume mixes it is possible to sow
the grasses in the fall and no-till drill or broadcast the legume in the same
field the following spring.
*Related Habitat How-To references: