J. Troy Johnson & R. Dewey Lee, Extension Agronomists
Robert L. Stewart, Extension Animal Scientist
Planning a Forage System
Forage Quality
Determining Forage Requirements
Guidelines to Estimate Pasture Requirements
Determining Soil and Climate Capabilities in Supporting Pastures
Types of Pastures
Pasture Plants
Symbiotic Nitrogen Fixation
Establishing Pastures - General Guidelines
Overseeding Summer Perennials with Winter Annuals
Pasture Fertilization
Grazing Management
Weed Control
Pasture Management
Other Sources of Information
Grassland agriculture is a farming system that emphasizes the importance of grasses and legumes in livestock and land management. Grassland agriculture is a good soil and water conserving practice because it reduces soil and water loss as well as stream pollution.
Pastures provide inexpensive high-quality livestock feed in the form of grazing, hay or silage. Pasture and hay crops can supply nearly all of the feed required for a cow-calf livestock system and can contribute significantly as feed sources for dairy and stocker beef systems. In the future, forages will be more widely used in finishing programs for beef cattle as feed grains become more in demand for other uses. Forages can be effectively used in finishing programs to provide the leaner beef that the consuming public demands.
Improved pasture and cattle management programs provide additional income for many farms. Pasture and cattle production are easily adapted to part-time farming as well as full-scale livestock operations.
Many factors influence the success of a forage/ livestock operation. No one program or system fits all situations. Producers should find and use reliable information that is pertinent to their area. When planning a new forage program or trying out new technology, it is best to begin on a small scale that is easily manageable and expand as you learn or see the system is beneficial.
Factors to consider when planning a forage system include: land area available; location in the state; productivity of the soils; kinds of livestock that will use the forage; availability of resources and how intensively the operation will be managed. These factors influence the forage crops that should be grown, fertilization rates, the quality and distribution of the feed produced and the carrying capacity of the operation.
Evaluate each factor as it impacts your forage system and select those management practices that best fit your area, soil, climate and forage crop to maximize quality and production.
Good, timely management with good record keeping will pay extra dividends in maintaining a productive forage system.
Carefully consider forage quality when developing and managing a forage program. Quality refers to the nutritive or feeding value of a forage and affects the forage intake and digestibility by the animal. Quality indirectly refers to the plant constituents that influence an animal's use and performance.
The most widely used indicators of forage quality are total digestible nutrients (TDN), crude protein (CP), neutral detergent fiber (NDF) and acid detergent fiber (ADF). Other indicators such as net energy of lactation (NEL) and relative feed value (RFV) are derived from mathematical manipulations of NDF and ADF values.
TDN equates forage on an energy basis. The higher the TDN, the better the forage. NDF is analyzed chemically and consists of total fiber in the forage and relates negatively to animal consumption. ADF is composed of more indigestible fiber and relates negatively to digestibility. Crude protein is an expression of nitrogen concentration which is very important in animal productivity. RFV is a prediction of forage consumption and energy value.
High quality forage is more readily consumed and is used more efficiently than poor quality
forage. Animal performance improves as forage quality increases (Tables 1 and 2). The goal of
stocker operators is for calves to gain 2 pounds per day which requires forage that contains 67.5
percent TDN. Good milking beef cows require a minimum of 57 percent TDN. As milking
ability increases, the TDN requirement also increases.
| Table 1. Percent TDN in Forage and the Effects on Animal Performance | ||
| % TDN in Forage (Dry Matter Basis) |
Av. Daily Gain | Lb. TDN/Lb. Gain |
| 45 | .34 | 8.97 |
| 49 | .61 | 5.00 |
| 55 | .98 | 3.11 |
| 63 | 1.41 | 2.16 |
| Georgia Experiment Station - Dairy Animals Used | ||
| Table 2. Forage Digestibility and Milk Production | |||||
| Beginning Milk Production | Calculated Production when Pasture Digestibility Was: | ||||
| 55% | 60% | 65% | 70% | 75% | |
| 15 lbs. | 0 lbs | 3 lbs | 12 lbs | 22 lbs | 31 lbs |
| 20 | 0 | 6 | 16 | 25 | 34 |
| 25 | 3 | 9 | 19 | 28 | 31 |
| 30 | 3 | 12 | 22 | 31 | 44 |
| 35 | 6 | 16 | 25 | 34 | 47 |
| Persistance of Actual Milk Prod. | 69% | 78% | 87% | 97% | 107% |
| Georgia Experiment Station | |||||
The factors that influence forage quality are forage species, crop maturity, environment (climate),
fertility and pests. Forage crops differ significantly in forage quality. Cool season annual grasses
produce higher quality forage than summer perennials. Legumes produce high-quality feed with a
high level of protein. Generally, crops that grow in the cooler months produce a higher quality
forage than those that grow in the warm season. Alfalfa is an exception.
Regardless of species, forage feeding value is largely determined by its stage of maturity when grazed or harvested. Young, leafy vegetative growth has a higher level of digestible nutrients and protein which declines as the plants progress toward maturity (Figure 1). Older forage has fewer leaves, more stems and a higher fiber content. Seedhead development in pastures indicates decreased quality.
In the spring and early summer, warm season perennials produce leafy growth that has a higher percentage of leaves than the growth occurring in late summer and fall. Animal gains are higher during the spring. Managing pastures to utilize young forage throughout the grazing season improves animal performance.
The quantity, quality and distribution of forage required to support a cattle operation varies with the type of operation (stocker or cow-calf), the calving season and the level of management.
The carrying capacity of a pasture (cows/acre) is a function of the amount of forage produced. The forage species grown, level of inputs, management and weather influence how many cows or calves a pasture can carry. General guidelines on stocking rates are shown in a later section but experience is the best guide for the proper stocking rates for your operation.
Managing a forage program to meet the demand for quality forage is important. Young cattle especially need quality forage to maintain an acceptable rate of gain. Lactating cows need higher quality forage than dry, pregnant cows. Managing the forage program to produce the kind of forage needed is a key to having a profitable operation.
The annual TDN and crude protein requirements for a brood cow are given in Figure 2. The most critical period is from birth to three months of age. If nutritional needs are not met during this time period, weaning weights will be reduced and conception rates will be lower. The second three month period is also important for milk production and growth of the calf.
Traditionally, in Georgia, calving seasons are either in the fall (October-December) or in late winter (January-March). Meeting the nutritional needs of a brood cow with pasture at these times of the year is difficult. Fescue/clover pastures are dependable in late fall and spring in north Georgia. In the southern part of the state, bahiagrass and bermudagrass pastures are productive in spring but winter annuals planted on prepared seedbeds or rygrass and clover overseeded onto perennial grass pastures will be necessary for successful fall calving.
Selecting forage crops and management practices which meet the needs of the cattle during growth and production cycles is the key to efficient forage utilization.
In planning a forage-livestock system, remember that the growth period of specific forage plants
cannot be altered. However, a cattle production system can be adapted to fit forage growth
patterns.
The amount, quality and distribution of forage needed depends on the type of livestock operation. The amount of forage that can be produced is influenced by soil productivity and crop management. These guidelines are for average conditions. More or less pasture may be required.
Good pastures are easier to establish on soils that will produce good row crops. Soils not well-suited for row crops can be used for pastures; however, lower productivity usually results. Land that can be used economically for pastures include areas with little top soil, areas with rolling slopes, areas too rough to cultivate, and areas that are too wet to produce row crops.
When a pasture area is selected, choose plants best-adapted for the particular soil. Land with good top soil, good soil structure and good drainage will respond favorably to intensive management practices, resulting in high-yielding pastures.
Fertile upland soils and areas along streams make excellent pastures. Good pastures can be produced on almost any land used for crops. Dry weather occurs in the spring, summer and fall. Use drought-resistant plants for upland summer grazing.
The rich cove lands are well-adapted to perennial and annual pastures. Winter annual pastures can be planted on any of the cultivated soils of this region. However, the upland soils are easier to handle because of better drainage. This region has abundant rainfall.
The best land for pastures in this region is along streams. The low, moist areas, if adequately drained, are excellent for summer pastures. The better upland soil is good for spring and fall grazing crops. Dry weather often occurs in spring, summer and fall. Use drought-resistant plants on the uplands for summer grazing.
Land that produces row crops will produce pastures in this region. Some of the better areas will produce winter and summer annual pastures. Plant sand ridges with a hybrid bermuda for hay and grazing.
The best pasture soil is in moist areas along streams. However, good results can result on the better uplands. Winter annual pastures do best on upland soils. Soils in this region are usually heavier and more fertile than those of the middle and lower Coastal Plain.
The best pasture soils are on good uplands and well-drained lowlands. Most of the uplands can produce winter annual pasture and perennial summer pasture.
Poorly-drained soils in this region are not suitable for pasture use. Soils that have sufficient drainage for row crops can be used for permanent and annual pastures.
Permanent pastures are established in perennial warm or cool season grasses and legumes that persist for several years. Temporary pastures are seeded each year with cool or warm season annual grasses and legumes. Temporary pastures are usually plowed and a seedbed prepared each year.
A wide variety of both annual and perennial grasses and legumes can be grown in Georgia. When selecting a forage crop or mixture of forage crops for grazing or hay production, consider the following factors:
Perennial grasses are widely used as the base crop for permanent pastures. Grow perennial or reseeding annual legumes with perennial grasses where they are adapted. Annual grasses and legumes can be used for winter or summer temporary grazing. Temporary pastures provide high-quality forage that can be used in stocker programs or used to supplement permanent pastures for beef cows.
Perennial warm season grasses grow during the warmer part of the year and persist for several years when well managed. These grasses are dormant during the winter.
Bermudagrass is a high-yielding, sod-forming grass that is well-suited for grazing or hay production. It grows best on well-drained, fertile soils where ample moisture is available. Bermudagrass does not persist on poorly-drained flatwoods soils but can be successfully grown on deep sandy soils because of its deep root system.
Several varieties of bermudagrass are grown in Georgia, ranging from common bermuda to the high-yielding, good quality hybrid bermudagrasses. The hybrid bermudagrasses respond to high N levels (200 to 400 pounds per acre) in a hay production program. These grasses can be cut four to five times per year and produce 4 to 6 tons of hay per acre when moisture is not limiting. When these grasses are used for grazing, manage the stocking rate to keep the grass closely grazed to maintain good forage quality.
Significant advances have improved bermudagrass yields and forage quality. Dr. Glenn Burton, plant geneticist at the Georgia Coastal Plain Experiment Station and the leader in improving bermudagrass, has developed several hybrid bermudagrasses for southern forage programs. His most productive releases include Coastal, Tifton 44, Tifton 78 and Tifton 85.
Coastal Bermudagrass was the first hybrid forage bermudagrass developed for southern forage programs. Coastal (an F1, hybrid of Tift common bermuda and a bermudagrass introduced from Africa) was released nearly 50 years ago and has been established for hay and grazing on approximately 15 million acres in the southern United States. In Georgia, Coastal is best adapted to the Coastal Plain and lower Piedmont areas. It is not as cold tolerant as Tifton 44 and can winter-kill in the mountains.
Coastal produces high yields of good quality forage when properly fertilized and managed, but like all hybrid bermudagrasses, Coastal produces few viable seed and must be established from sprigs.
Tifton 44, a winter-hardy hybrid bermudagrass is a cross between Coastal and a winter-hardy bermudagrass from Germany. This hybrid produces more rhizomes than Coastal and is better adapted to the northern area of the bermudagrass growing region of the country. Tifton 44 bermudagrass produces higher quality forage than Coastal or Alicia, averaging seven percent higher than Coastal and 10 percent higher than Alicia in digestibility. Hay yields are similar to Coastal and Alicia. Tifton 44 grows earlier in spring and later into the fall than Coastal or Alicia. Tifton 44 must be established from vegetative planting material (sprigs) and can be more difficult to establish than the other forage bermudagrasses.
Tifton 78, released in 1984, is a cross between Tifton 44 and Callie. Compared with Coastal, Tifton 78 grows taller, has larger stems and a similar rhizome system, spreads much faster, is more easily established and starts growth earlier in the spring. In tests at Tifton, this new hybrid produced 25 percent more dry matter (hay yields) and averaged 7.4 percent higher in digestibility than Coastal.
Tifton 78 is not as winter hardy as Coastal or Tifton 44 but can be grown throughout the Coastal Plain. Tifton 78 is most susceptible to cold damage during the first winter after establishment. Established stands which are not cut for hay or fertilized with N after mid-August should survive. Allowing the grass to go into the winter with 6 to 8 inches of top growth increase winter survival. Stands of Tifton 78 have not been as persistent as Coastal or Tifton 44.
Tifton 85 released in 1992 is a highly digestible hybrid cross of Tifton 68 and an introduction from South Africa. It has larger stems, broader leaves and a darker green color than other bermudagrass hybrids. At the Coastal Plain Station, Tifton 85 produced 26 percent more forage that was 11 percent more digestible than Coastal. In a comparison with Tifton 78, Tifton 85 produced more live-weight gain per acre. It has large rhizomes and stolons that spread rapidly and cover quickly. Stolons may grow 2 to 3 inches per day and develop roots and top growth at each node. Tifton 85 produces fewer rhizomes than Coastal and is not as cold tolerant as Coastal or Tifton 44. Tifton 85 is best adapted to the Coastal Plains region.
Alicia bermudagrass was selected from a group of bermudagrass introductions from Africa and marketed by a private businessman in the early 1970s. Alicia is relatively easy to establish and produces high hay yields (similar to Coastal and Tifton 44) but its forage is lower in quality than Coastal (about 10 percent less digestible). Alicia, like Callie, is susceptible to rust, a foliage disease that destroys leaf tissue and reduces yields and quality. Alicia can be grown throughout the Coastal Plain and lower Piedmont areas.
Florakirk is a fine-stemmed hybrid cross between Tifton 44 and Callie. Developed by Dr. Glenn Burton and released by the University of Florida, Florakirk has greater dry matter production than Coastal, Tifton 44, and Tifton 78 in Florida tests. Live-weight gains are similar to those obtained from Brazo bermuda-grass. Florakirk produces a high quality, fine stem hay that is 7 percent higher in digestibility than Coastal. This bermudagrass is not very winter hardy and is susceptible to leaf rust. It is best suited for production in south Florida.
Russell is a dense, low-growing productive hybrid bermudagrass. It was found in the late 1970s in a field near Seale, Alabama and was jointly released in 1995 by Auburn University and Louisiana State University. Limited testing shows Russell yields similar to Coastal and is more winter hardy. Forage quality appears to be similar. It spreads faster than other hybrids except Tifton 85. It has shown in greenhouse tests to root better from clippings than Coastal. It exhibits morphological characteristics similar to common bermudagrass.
Grazer is a hybrid selection between crosses of plant introductions from Italy and Kenya. It has large stems with wide leaves but is moderately productive in adapted areas. It was released from Louisiana State University and is comparable to Coastal in disease resistance, drought tolerance and persistence but produces 10 to 15 percent less forage. It's forage is more digestible than Coastal.
Brazos was released in 1982 from Oklahoma. In Georgia, it does not perform as well as other hybrid bermudagrass. Brazos has thicker stems and rhizomes and wider leaves than Coastal. It does not produce as dense a cover as other hybrids. It is more productive in the heavier soils in Louisiana and Texas.
The hybrid bermudagrasses produce few viable seed and must be established from vegetative plant material. Freshly dug sprigs (rhizomes or stolons) are the best source of planting stock for the bermuda-grasses that produce rhizomes. Although mature top growth can be used to establish stands, growing conditions must be very favorable for top-growth plantings to succeed.
Bermudagrasses can be planted from winter (February to mid-summer (late July in north Georgia and late August in south Georgia). Late winter plantings using dormant sprigs (sprigs that have not broken dormancy) have generally been very successful. Excessive moisture in winter limits the acreage that can be planted using dormant sprigs.
Plant the hybrid bermudagrasses, 30 to 40 bushels of sprigs per acre, into a moist well-prepared seedbed. Commercial sprigging machines that plant sprigs 2 to 3 inches deep and firm the soil around the sprigs do a good job. It is very important to firm the soil around the sprig to improve sprig survival. The sprigs should not be covered with more than about 1 inch of soil. Sprigs that covered too deeply may not survive, particularly on heavy clay soils that crust over after a rain.
Prior to planting, apply lime, P and K according to soil test recommendations. Apply 35 to 50 pounds of N per acre after the sprigs start to grow. With early planting dates, a second N application of 50 to 75 pounds will be necessary to promote rapid coverage.
Good weed control during the establishment phase is essential. Newly-established bermudagrass cannot compete with rapidly growing annual grasses and broadleaf weeds. A thick cover of weeds prevents the bermudagrass stolons from pinning down and slows stand establishment.
Pre-emergence herbicides help reduce weed competition in newly-established bermudagrass. Norflurazon (Zorial) has received a Section 18 label for use on establishing bermudagrass. No other herbicides are available for preemergence applications. Zorial controls many annual grasses and broadleaf weeds when applied after sprigging. Three to five days after application, rainfall or irrigation is needed for adequate weed control. The bermudagrass may temporarily have a slight growth suppression or chlorosis. However, it will grow out of this with time and will benefit from the weed control. After emergence, most broadleaf weeds can be controlled with 2,4-D. See the Georgia Pest Control Handbook for current recommendations. Check with your county extension agent for the current label on norflurazon.
Common bermudagrass was introduced into the United States from India or Africa more than 150 years ago. It proved to be well-adapted to the humid South and quickly became a widespread weed in cultivated crops. Common produces viable seed and also spreads by stolons and rhizomes, so once it is established in a pasture, it is difficult to eradicate.
Common bermudagrass grows (usually in combination with fescue or as a contaminant in improved bermudagrass pastures) on more than 400,000 acres in Georgia. Because it is hardy, forms a dense sod, can be established from seed and can be maintained on infertile soils, common is well-suited to conservation uses.
Although common does not provide high yields (only 50 to 60 percent as much hay per acre as Coastal) it can be effectively used in forage programs to provide summer grazing. In North Georgia it is best used in combination with fescue and clover.
Pasto Rico and Campo Verde bermudagrasses are marketed by commercial seed companies. These common bermudagrasses are a mixture of a common giant bermudagrass and the normal low-growing common bermudagrass. We have not evaluated these varieties and do not have performance data. Observations indicate that the giant bermudagrass is not cold tolerant and persists for one to four years. The low-growing common is cold tolerant and persists for many years.
Cheyenne is a commercially-available selection or variety of a high yielding common bermudagrass that may have potential for use as a grazing or hay crop in Georgia. Cheyene has been evaluated for yield and persistence at several locations for three years. It has produced high yields (similar to Coastal) and the stands have persisted. We need to evaluate the grass for several more years to be sure about its persistence but we are cautiously optimistic that this is a high yielding bermudagrass that we can establish from seed.
Plant 5 to 8 pounds of common bermudagrass seed per acre into a moist, well-prepared seedbed in spring to early summer. Seed can be drilled or broadcast and cultipacked to firm the soil. Do not graze or harvest for hay until the plants are well-established. With good growth conditions, spring plantings can be grazed in late summer.
Weeds can be a problem in new plantings. Broadleaf weeds can be controlled with 2,4-D after the bermudagrass is 4 to 6 inches tall. Crabgrass and other annual grasses cannot be controlled with herbicides and mowing may be necessary to keep crabgrass from dominating the stand.
Bahiagrass is a deep-rooted perennial adapted to a wide range of soils in the Coastal Plain region. It spreads by short, stout stolons and is a prolific seed producing plant. Bahiagrass will grow on soils too poorly-drained for bermudagrass, is more shade tolerant than bermudagrass and can be used in woodland pastures. It does not respond to high fertility as well as bermudagrass and will persist in pastures with a low level of management.
Bahiagrass forage is slightly lower in quality than Coastal bermudagrass. Close grazing is necessary to obtain good utilization. It is not a good hay crop because most of the leaves are close to the soil surface. Bahiagrass can become a pest in hybrid bermudagrass hay fields. Keep this in mind when rotating cattle, because seed will germinate after passing through cattle. Bahiagrass introduced to a field (through seed in the droppings of cattle) can crowd out already-established bermudagrass.
Pensacola has long narrow leaves and is the most widely-grown variety. It was introduced into the United States from South America in the late 1930s (probably in ballast discarded from ships visiting the port at Pensacola, Florida). Pensacola is more winter hardy than the common and Argentine varieties. Growth begins early in the spring and continues until mid-summer when the seedheads mature. Late summer growth is slow and low-quality. Pensacola is fairly resistant to ergot, a smut disease affecting the seedheads of some grasses and causing health problems in cattle.
Use Pensacola on the poorer, less fertile soils of the Coastal Plain and in pastures which will not be intensively managed. Once Pensacola is established, it can be maintained more easily than most pasture grasses. Winter annual grasses and legumes seeded in bahia sods in the fall will provide grazing in winter and early spring without harming bahia stands.
Tifton-9, a new variety of Pensacola bahia, was developed at the Georgia Coastal Plain Experiment Station. Tifton-9 is high-yielding, more vigorous and has better seedling vigor than Pensacola. It has produced higher hay yields than Pensacola and can be established with 8 to 10 pounds of seed per acre.
Argentine is not as frost-tolerant as Pensacola and is not widely grown in Georgia. It has broader, darker green leaves than Pensacola and may be better adapted to poorly-drained soils. It seeds and spreads like Pensacola. Argentine starts growth later in spring but produces more forage in late summer and early fall than Pensacola. It is very susceptible to ergot.
Common has short, broad leaves with stout stolons. It produces lower yields than Pensacola and is not cold hardy. Common can be grown only in the lower Coastal Plain. It starts growth later in spring but produces higher quality forage in summer and fall than Pensacola.
Bahiagrass is best established on a well-prepared seedbed in early spring on upland soils or in late spring on low, moist soils. Bahiagrass can be successfully seeded in the fall in extreme south Georgia. Broadcast or drill 12 to 15 pounds of seed per acre and cover seed 1/4 to 1/2 inch deep. A cultipacker-seeder works well. Apply 40 to 50 pounds N per acre after the seedlings start to grow. Allow the seedling plants to become established before grazing. If crabgrass becomes a problem, grazing or mowing will be necessary to prevent the crabgrass from shading the bahiagrass seedlings.
Dallisgrass is a fast growing, stout perennial used primarily for pasture. It is not suitable for hay production. It has smooth leaves, a deep root system and grows in clumps of few to many stems. Numerous leaves occur at the base of the plant, but few leaves are found on the stems. The slender stems tend to droop when seedheads develop. Dallisgrass is susceptible to ergot.
Dallisgrass is adapted to low, moist areas and also produces well on fertile uplands. Make sure the soil is productive with a comparatively high fertility level. A legume, such as one of the recommended white clovers, can be grown with this grass to improve forage production and quality.
Seed 12 to 15 pounds of high-quality seed per acre on a well-prepared seedbed from early spring until early summer. Spring plantings (March) are generally more successful.
Carpetgrass is a low-growing, creeping perennial that forms a dense sod. It has compressed, two-edged stems that root at each node (joint). The leaf tips are blunt. Carpetgrass is normally found in moist areas throughout the Coastal Plain and lower Piedmont. It will tolerate close grazing but is not as productive and produces lower quality forage than improved forage grasses. Do not seed carpetgrass for pasture because it is difficult to eradicate.
In areas already in carpetgrass, the quality and quantity of forage can be increased by liming, fertilizing and seeding a legume, such as white clover and annual lespedeza, into the stand.
Johnsongrass is a tall-growing, broad leaf perennial that spreads by rhizomes and seed. The rhizomes (underground stems) send up shoots from the joints to produce new plants. Johnsongrass is best adapted to moist fertile soils and can be grazed or harvested for hay or silage. Close continuous grazing will weaken stands and reduce production. Johnsongrass belongs to the sorghum family, and when stressed by dry weather or cold temperatures it can develop prussic acid, which is toxic to livestock.
Warm season annual grasses are established from seed and are productive during spring and summer. These plants are frequently used as temporary forage for stocker cattle and mature cows. Warm-season annual grasses such as pearl millet, and sorghum-sudangrass hybrids are tested yearly at the Georgia Experiment Station. The data is published in the annual Field Crops Performance Test Bulletin. Check with your county extension agent for a current copy.
Pearl Millet is a high-yielding summer annual that can be grown on well-drained soils throughout the state. Millet produces good quality forage and supplies grazing from June through August. This tall growing, erect annual grass produces several stems from a central plant. Millet planted in spring (April) should be ready for grazing 30 to 40 days after planting and should be productive for 80 to 110 days. The crop is most productive during the first 60 days of the life of the stand.
Good grazing management is important to maintain productive stands. Start grazing when the plants are 18 to 24 inches tall. Graze down to a stubble height of 6 to 8 inches, then remove cattle and allow the crop to regrow before starting another grazing cycle. Well-fertilized millet should carry three to four stocker cattle or two to three mature cows per acre during the first 60 days. Lower the stocking rates during the last part of the grazing season. Even out the grazing supply over the summer by making multiple plantings. Plantings made in early June will be in peak production when April plantings are starting to decline in productivity.
Good millet stands utilize 150 to 200 pounds N per acre. Apply 40 to 60 pounds N per acre at or just after planting and 40 to 60 pounds per month for the first 60 days. Reduce N rates after the crop growth rate slows down.
Several hybrid millets are marketed in Georgia. Most hybrids are tall-growing and produce high yields. Tifleaf-1 hybrid millet is a dwarf, low-growing millet that is excellent for grazing. It produces leafy forage and will provide higher average daily gains than the taller hybrids. Tifleaf-1 does not produce as much total forage and will carry fewer animals per acre than the tall hybrids. Gains per acre will be similar, however, because of the higher daily animal gains with the more leafy dwarf hybrid. Tifleaf-2 is a new dwarf hybrid millet that is similar to Tifleaf-1 in appearance. Tifleaf-2 is higher yielding than Tifleaf-1 and is resistent to Pyricularia leafspot, which reduces Tifleaf-1 yields in late summer.
Sorghum x Sudangrass Hybrids are tall-growing annuals similar to millet in growth habit, yield and carrying capacity. They are best adapted to fertile soils where the soil pH is 5.8 or higher and are more productive in late summer than millet. These hybrids can cause prussic acid poisoning of cattle when young forage is grazed after severely dry weather or when cold temperatures limit growth. Cases of prussic acid poisoning are relatively rare in Georgia.
Sudangrass is another annual grass that can be used for grazing, hay or silage. It produces lower yields than millet or the sorghum x sudan hybrids and requires fertile soils with a pH of 5.8 or higher.
Establish these summer annual grasses on well-drained fertile soils. Plant them after the soil temperatures are above 65 degrees F (April in south Georgia to May in north Georgia). Two plantings made four to six weeks apart provide good quality forage throughout the summer.
Drill the seed 1/2 to 1 inch deep into a prepared seedbed. Broadcast plantings can be successful but a higher seeding rate is required. Seeding rates are: millet - 12 to 15 lbs/A in rows or 25 to 30 lbs/A broadcast; sorghum x sudangrass hybrids - 20 to 25 lbs/A in rows or 30 to 35 lbs/A broadcast; sudangrass 20 to 25 lbs/A in rows or 30 to 35 lbs/A broadcast.
These crops respond to high rates of fertilization. Apply a complete fertilizer (according to soil test results) before planting. Apply 40 to 60 pounds N per acre at planting or soon after plants emerge. Make subsequent N applications about every four weeks during the growing season.
When plants become stemmy, mechanically clip them to a height of 10 to 12 inches and fertilize with N. With good grazing management, clipping is not necessary.
Browntop Millet is used for grazing or hay. It produces lower yields than pearl millet and has a shorter productive season. Browntop millet is a good reseeding plant and the seed may remain viable in the soil for many years. It can become a pest in cultivated crops. To establish browntop millet, broadcast 20 to 25 pounds of seed per acre on a prepared seedbed in spring.
Crabgrass is a low-growing annual grass present in most cultivated fields and pastures in the state. It is a good reseeding plant that can furnish summer grazing following winter annual grazing mixtures or legumes harvested for seed. Crabgrass is not drought tolerant and grows best when soil moisture conditions are good. Forage is very digestible and palatable. Cattle will usually selectively graze crabgrass in preference to fescue, bahia or bermudagrass. The productive season is from May until October. Red River is the only commercially-available variety.
Tall Fescue is a cool season perennial well-adapted to the Piedmont, Mountain and Limestone Valley regions of Georgia. Over 1 million acres of tall fescue are used for pasture in north Georgia. Fescue is a deep-rooted bunch grass that is productive during fall, late winter and spring. More than half of the total yearly production occurs in spring. It does not grow well in mid-summer unless moisture conditions are favorable.
Fescue produces its highest yields along creek bottoms in north Georgia. Production declines on hillsides and ridges as moisture becomes limiting. Tall fescue does not grow well in the Coastal Plain region.
Use tall fescue for grazing and hay production. Forage quality and feed distribution are improved when an adapted legume (such as white clover or red clover) is grown in association with fescue. Close grazing keeps forage quality high and also helps keep clover in the stand. Fescue does not respond to high N rates. Pure stands can use up to 100 pounds N per acre. When clover comprises at least 15 to 25 percent of the stand, reduce N rates to 20 to 30 pounds per acre.
Most tall fescue pastures in Georgia and other states are infected with a fungal endophyte, Acremonium conenophialum, which grows inside the fescue plant. Highest concentrations occur in the stems, leaf sheaths and seeds. The fungus is spread by planting infected seed.
The fungus has a detrimental effect on cattle that graze infected pastures or consume hay cut from infected pastures. Cattle gain less weight and reproductive problems are common (such as reduced conception rates and reduced milk production). Other symptoms include a slightly-elevated body temperature, heat intolerance (cattle stand in the shade more than normal), excessive nervousness and failure to shed winter hair coats in the spring.
The infection level within a fescue pasture can range from low to very high. Research at the Southern Piedmont Station at Watkinsville has shown a direct negative correlation between infection level and animal gains. A 10 percent increase in infection level reduces animal gains by about 1/10 pound per day.
Your options in dealing with fescue toxicosis range from interseeding legumes into pastures to destroying infected stands and replanting with seed of a fungus-free variety. The first step in developing a strategy to deal with fescue toxicosis is to determine the severity of the problem in your operation. Animal performance is the best indicator. Problems are minimal in operations where the calving percentage is over 90 percent and calf weaning weights exceed 500 pounds. On the other hand, low calving percentages (60 to 70 percent) and low weaning weights (300 to 400 pounds) indicate a significant problem with either the fescue or the cow management program.
Handle pastures that have low levels of infection, less than 30 percent, by interseeding legumes (white clover or red clover) and planting other grasses, such as common bermuda, dallisgrass or orchardgrass, to replace some of the fescue. These suggestions are also appropriate for pastures with moderate infection levels (30 to 75 percent). With these pastures, replace more of the fescue with other grasses. Renovation is the best option for pastures that are highly infected (75 percent or higher) when the soils can grow fungus-free fescue.
The fungus-free varieties are not as persistent as infected Kentucky 31 under stressful conditions, such as drought and overgrazing and frequently are more difficult to establish. These varieties are best-adapted to good soils along creek bottoms and upland soils that are not severely eroded. If your soils cannot grow the fungus-free varieties, incorporate legumes and other grasses into your forage program.
Renovating Infected Fescue Pastures. Completely renovating an infected fescue pasture to establish a fungus-free variety is a major operation. The renovated pasture will be out-of-production for six to nine months. Make plans to supply extra feed or reduce cattle numbers during this period.
The three parts in a renovation program are: destroying the existing infected stand, seeding the new variety and managing the new planting.
Destroying Old Stands. Kill the existing fescue in late summer by plowing or use a herbicide. Chemical renovation can be faster and cheaper since several tillage operations are needed to eliminate the fescue. Killing fescue pastures with a herbicide and sodseeding fungus-free seed into the killed sod is advantageous for pastures with severe slopes. Two applications of Granoxone Extra in the fall will kill at least 95 percent of the fescue. Apply 1 to 1.5 pints on fescue that is 6 to 8 inches tall and actively growing (three to four weeks before planting). Make the second application (1.5 pts/A) three to four weeks later. Use a non-ionic surfactant with the Granoxone Extra. Roundup is more expensive and less effective on fescue but should be used when common bermuda and other perennial weeds are a problem. Apply one quart/acre 21 to 28 days before planting and another quart/acre at planting.
Seeding the New Variety. Sod seed fungus-free fescue into the killed sod with a grassland drill by early October in the Piedmont. Seed earlier in the mountains (September) or wait until spring to seed the fescue.
Drought and insects frequently cause problems with fall seedings. Dry weather can reduce germination and delay seed emergence. Stands that are not well-established by December can winter-kill. Insects (grasshoppers and crickets) which inhabited the fescue sod can damage new seedlings.
Planting fescue into a prepared seedbed is generally more successful than sodseeding. Seedlings emerge faster, are more mature by late fall and have more cold tolerance. Soil heaving (alternate freezing and thawing of moist plowed soils) can cause stand problems.
At this point, you have two options. One is to plant a endophyte-free variety by October. The disadvantages are that some of the old fescue may have survived and seed that was produced in the spring may germinate and contaminate the new stand.
The second option is suitable for many operations. After preparing the seedbed in the fall plant a small grain (rye or wheat) for winter grazing. Do not plant ryegrass where fescue will be seeded. Graze the small grain until spring. Plow in late spring to incorporate lime, if needed, and plant pearl millet or sorghum hybrids for summer grazing. Plow the area again in August and allow the seedbed to collect moisture before planting endophyte-free fescue in September. With this program all of the old fescue will be killed, and seed from the old stand will not be a problem. But plowing is expensive and the cost per acre will be higher.
Managing endophyte-free fescue. Maintain endophyte-free fescue stands with good management. These varieties are not as drought tolerant or as persistent under heavy grazing as most infected varieties. Do not graze pastures closely. Maintain at least 3 to 5 inches of growth in the pasture at all times. When pastures are under moisture stress, reduce the stocking rate to avoid overgrazing. New plantings need special treatment. Do not cut new plantings for hay in the spring. These pastures can be lightly grazed in the spring.
Several varieties of fescue are now available. Some produce more forage in winter and fall than Kentucky 31, the most common fescue although total yields for the year will be similar. Some are endophyte-free and produce similar or better yields than Kentucky 31. The winter productive varieties are good choices for the lower and middle Piedmont. None of the varieties produce much forage in winter in the mountain region.
Kentucky 31 is the most widely-planted fescue in the United States. It originated on a farm in Eastern Kentucky and was released as a variety by the Kentucky Agricultural Experiment Station. Most existing pastures of Kentucky 31 are heavily infected with the endophyte fungus.
Georgia 5 was released by the University of Georgia in 1992. It is well adapted to the southeastern United States and was developed to increase fescue's adaptation to coastal plain soils. It is the only variety acceptable for use in the coastal plains region. It has excellent forage yields and is well adapted to sandy loam soils. It should not be planted on droughty sands or soils prone to prolong drought conditions.
Au Triumph was the first of the endophyte-free varieties. It was developed at Auburn University. Au Triumph forms on open sod and is more winter productive than other varieties. It has been found to be less persistent than other endophyte-free varieties. In central Georgia it will provide four to six weeks more grazing than other varieties.
Cajun is very similar to Au Triumph in growth habit and produces similar yields. Cajun is a better seed producer than Au Triumph.
Forager is a variety developed by Farmers Forage Research, Inc. Little data is available on this variety in comparison with others. Where it has been tested it seems to yield well.
Martin was released by the Missouri Agricultural Experiment Station. It is a good yielding variety in Georgia.
Stargrazer is a new variety from Farmers Forage Research, Inc. It appears to be more productive than Kentucky 31. Little data is available.
Jesup, the newest release from The University of Georgia, is more persistent than other endophyte-free varieties. It has shown better summer survivorability than other varieties. In studies in Georgia, animal gains have been excellent. It has good productivity in the Piedmont and mountain regions. It is not recommended for the coastal plains region of Georgia.
Other varieties tested in Georgia and found to be acceptable are Phyter, Festorina, Fuego and Southern Cross. For the most recent comparison of yield data, check The University of Georgia research bulletin no. 423, Cool-Season Grass Cultivar Trials in North Georgia.
Orchardgrass is adapted to the more fertile soils in the mountain and upper Piedmont areas. It is a bunch grass that produces an open sod, produces excellent quality forage and can be grazed or cut for hay. It is not as persistent as tall fescue, and stands usually thin after a few years. It is susceptible to leaf diseases and does not tolerate close continuous grazing. Grow orchardgrass with a legume, such as white clover or red clover. Mixtures of tall fescue and orchardgrass are widely used in the upper Piedmont and Mountain regions. Hallmark, Benchmark, Summergreen and Shiloh are acceptable varieties.
These grasses are best established on a prepared seedbed. Fall seedings are more successful in the Piedmont while early fall and spring seedings work well in the mountains. Plant 12 to 15 pounds of orchardgrass and 2 to 3 pounds of white clover seed, or 6 to 8 pounds of red clover seed, 1/4 to 1/2 inch deep, using a grain drill or sod seeding drill. When seed are broadcast and incorporated by disking or dragging, increase the seeding rate by 25 percent.
Bluegrass is adapted to the Mountain and upper Piedmont regions. It furnishes grazing during late winter and spring and grows well with white clover. Bluegrass is a low producer and is not recommended for planting.
Rescuegrass is a short-lived bunch grass closely related to bromegrass and cheat or chess. It is produc-tive in late winter and spring. It is a prolific seeder; do not plant on areas where crops are harvested for seed in spring. Rescuegrass requires high fertility and is not recommended for use in Georgia.
The cool season annual grasses are productive in late fall and spring and widely grown throughout Georgia. They provide high quality grazing as either overseeded in permanent pastures or on a prepared seedbed.
The University of Georgia test small grains for forage production each year. Check with your local county Extension agent for a current copy of the Small Grains Performance Test Bulletin.
Rye is the most drought tolerant and winter hardy small grain grown in Georgia. It can be planted in early fall and usually produces good grazing by late fall. Rye produces more forage in late winter than the other small grains. It matures early and is well-suited for grazing on rowcrop land that must be plowed in early spring for summer row crops. Forage quality declines in spring as the plants become stemmy and leaf production decreases. Adding ryegrass or annual legumes extends the grazing period.
Oats are a small grain often used for winter grazing in Georgia. When seeded in mid-fall, they furnish grazing in late fall and spring. Oats are not as cold hardy as rye and can winter-kill during harsh winters. This crop produces more grazing in spring than rye and can be cut for hay or silage. An oat- ryegrass-clover mixture produces more total forage over a longer grazing season than oats alone.
Wheat is a winter-hardy small grain that provides forage in late fall, early winter and spring and is suitable for grazing or silage. When ensiling wheat, cut the crop in the late boot to early bloom stage of growth. For best results, wilt the crop to 25 to 30 percent dry matter before chopping and ensiling. Wheat can be grazed in late fall and early winter and still produce a good grain crop. Remove cattle before the wheat starts to joint. Wheat works well in mixtures with other small grains, ryegrass and clovers.
Barley is a small grain used on fertile soils for grazing or grain in north Georgia. It is winter-hardy but produces less forage than the other small grains. Barley is susceptible to leaf diseases and is not widely grown in south Georgia.
Ryegrass is a well-adapted winter annual that can be planted in prepared seedbeds or overseeded onto perennial grass sods for late winter and spring grazing. Ryegrass is usually seeded in mixtures with a small grain and clover on a prepared seedbed. It is a prolific seed producer and will reseed in pastures. Ryegrass has a longer grazing season than the small grains and can be grazed until early May in south Georgia and early June in north Georgia when moisture is adequate.
Establish small grains in the fall on well-drained fertile soils. Ryegrass will grow well on soils too wet for the small grains. These crops can be seeded in late August in the mountains, early September in the Piedmont and late September in the Coastal Plain. Treat small grain seed with an approved fungicide prior to planting. Seedling diseases such as helminthosporium, rhizoctonia, pythium and others reduce stands when planted in the warmer months of September and October, especially in south Georgia.
When practical, prepare the seedbed two to three weeks before planting. Allow the soil to collect moisture and settle to improve seed germination and seedling development. Although deep soil preparation is not necessary for the grazing crop, deep tillage may benefit row crops planted in the spring.
Seed can be placed more precisely with a drill or cultipacker seeder than by broadcasting and disking. When seed are broadcast, increase the seeding rate by 25 percent to allow for variable seed placement. Plant small grain seed 1 to 1-1/2 inches deep in moist soil. Do not plant ryegrass and clover seed deeper than 1/2 inch. When planting ryegrass and small grain pastures, many farmers broadcast ryegrass seed then drill the small grain seed into the seedbed. Seeding rates for winter annual crops are shown in Table 3. Seeding rates of cool season annual legumes are in Table 4.
Apply 40 to 60 pounds N per acre soon after the plants emerge to increase growth and provide earlier grazing. A second N application of 60 to 80 pounds in mid-winter will increase winter and spring forage production. A third N application may be needed when ryegrass is used for late spring grazing.
Begin grazing as soon as the plants are well-established and have accumulated 4 or more inches of growth. Overgrazing or grazing when the soil is too wet (when animals can bog in the soil) decreases potential production. Excessive growth during the winter can be killed by extremely cold weather. Winter annual grazing may be used more efficiently by limiting the amount of time cattle are permitted to graze. Consider the forage quality, nutritional needs of the cattle, amount of forage present, availability and the cost of other feed items when deciding how much time to permit the cattle to graze.
Consider alternative land use, crop rotation and forage value in deciding when to terminate
grazing. If ryegrass and legumes are permitted to mature seed, a volunteer crop will usually
develop the following fall.
| Table 3. Seeding Rates for Winter Annual Grazing Crops in Pure Stands or Mixtures | ||
| Crop | Seeding Rate per Acre | |
| Pure Stands | Mixtures | |
| Rye | 2 bu. | 1 to 1-1/2 bu. |
| Wheat | 1 to 1-1/2 bu. | 1 to 1-1/2 bu. |
| Oats | 3-4 bu. | 2 to 2-1/2 bu. |
| Ryegrass | 30-40 lbs. | 20-25 lbs. |
| Crimson clover | 15-20 lbs. | 10-15 lbs. |
| Arrowleaf clover | 6-8 lbs. | 5-6 lbs. |
| Vetch | 15-20 lbs. | 10-12 lbs. |
Warm season perennial legumes are productive during the warmer months and live for more than one year.
Alfalfa is a high-yielding crop that is well-suited for hay or silage production. It produces excellent quality, high protein forage that can be used in beef, dairy and horse rations. Alfalfa grows best on deep, well-drained soils with good moisture holding capacity. It develops a deep root system if root growth is not restricted by hardpans, high water tables or acid subsoil. Alfalfa can be grown throughout the state where suitable soils occur. Stands in south Georgia generally have a shorter life (three to five years) than stands on the heavy clay soils in the Piedmont and Mountain regions where stands can persist for four to seven years or longer. Alfalfa can be cut four to six times per year at 30 to 40 day intervals. Alfalfa is most productive in spring, early summer and fall. About 60 percent of the annual production occurs in spring and can be rotationally grazed without harming the stands. This crop has a high lime requirement (pH 6.5 to 7.0) and must be well fertilized and properly managed to maintain productive stands.
Seed alfalfa on a well-prepared, firm seedbed. Seed 18 to 25 pounds of inoculated seed with a cultipacker-seeder or broadcast seed and cultipack after seeding. Cover the seed with 1/4 to 1/2 inch of soil. Preferred seeding dates are late August in the mountains, mid-September in the Piedmont and early October in the Coastal Plain. Some stands of fall-planted alfalfa in the Piedmont and Mountain regions have been severely affected by Sclerotinia. This fungal disease, which affects alfalfa in the spring after fall seeding, affects fields that have grown clover in recent years. Spring planted stands are not affected. When establishing alfalfa in north Georgia, plant in the spring (March) if clover has been grown on the field in past years.
Several high-yielding alfalfa varieties are well-adapted to the Piedmont and Mountain regions. Suggested varieties include Alfagraze, Apollo Supreme, Cimarron VR, and DeKalb DK133.
Alfagraze, a new alfalfa variety released by the University of Georgia, is the only variety that tolerates grazing without stand loss in Georgia. It is also an excellent hay variety that yields as well as other adapted varieties. The best use for this new variety is where the crop will be grazed at least a portion of the year. While this variety experiences winter dormancy, a new release from The University of Georgia, AmeriGraze 702 is considered to be nondormant and will resume spring growth faster than Alfagraze. In mild winters, AmeriGraze 702 will provide winter grazing without dormancy. It is a productive variety for the lower Piedmont and coastal plains region of Georgia. It has a longer productive season than Alfagraze. In severe winters, some damage may occur in the lower Piedmont areas. AmeriGraze702 is the only variety recommended for use in the coastal plain region of Georgia. It is suited for both grazing and hay production.
Perennial Peanut is a rhizomatous peanut that produces high-quality grazing and hay. It is best suited to south Georgia on well-drained sandy or sandy loam soils. The only varieties suitable for planting in Georgia are Florigraze and Arbrook. They do hot have good cold tolerance and will winter kill during severe winters. Perennial peanuts are established by planting rhizomes during December to early March at 60 to 80 bushels per acre. Perennial peanut may require up to two years of growth after sprigging to establish a good stand. Crude protein ranges from 13 to 20 percent depending on maturity.
Serecia Lespedeza is a long-lived, deep-rooted, drought resistant perennial that will grow on heavy, well-drained soils throughout the state. Serecia grows erect, with stems two to four feet tall and can be used for grazing, hay or soil conservation. It responds well to fertilization but can be grown on soils too acidic and infertile to support other forage legumes. Serecia is frequently used for cover on roadbanks to prevent erosion.
Manage serecia to keep the plants vigorously growing. Rotationally graze when plants are 6 to 8 inches tall. Harvest for hay when plants reach a height of 15 to 18 inches. Serecia provides good quality forage in summer when dry weather has reduced the growth of other forage crops.
Serala is an upright growing variety that has finer stems and more stems per plant than common.
Interstate is a leafy variety with fine stems and a prostrate spreading growing habit. It was developed for use on roadbanks but is suited for forage uses. The prostrate growth characteristic limits its use as a hay crop.
Serala 76 is similar in appearance to Serala and has resistance to three species of root-knot nematodes.
Interstate 76 is intermediate in height between Serala and Interstate and has a more open growth habit than Interstate. It produces higher yields than Interstate and is also resistant to three species of root-knot nematodes.
Au Lotan is an upright growing variety with small soft stems and is resistant to three species of root-knot nematodes. Au Lotan forage contains lower levels of tannin, is more digestible and provides better animal performance than the other serecia varieties. Yields are lower for Au Lotan (about 85 percent of Serala) and observations indicate that this variety has lower seeding vigor (making stands more difficult to establish).
Au Donnlley is a new low-tannin variety that is higher yielding, has better seedling vigor and is more persistent than Au Lotan.
Arlington is an upright variety that produces higher yields than common serecia.
Cericea has a branching growth habit and forms a thick dense canopy. It produces higher yields and is similar in quality to common serecia.
Seed serecia lespedeza on a prepared seedbed in the spring as soon as the last spring frost has passed. Use a cultipacker seeder to seed 15 to 20 pounds of inoculated, hulled, scarified seed per acre when a pre-plant incorporated herbicide has been used. Increase the seeding rate to 25 to 30 pounds per acre if no herbicide is used. Do not cover the seed with more than 1/4 inch of soil. Generally do not graze or cut for hay first year stands unless weather conditions have been excellent, resulting in rapid growth.
The warm season annual legumes are productive during spring and summer. They are not frost tolerant and do not survive winters.
Annual Lespedeza used for forage in the south consists of two species (striate lespedeza and Korean lespedeza) that were introduced from the Orient. They are adapted to a wide range of soils and fertility levels and are used in pasture mixtures to provide good quality grazing from late spring until fall. The annual lespedezas can be cut for hay but yields are relatively low. These plants are prolific seed producers and will reseed in pastures.
Striate lespedeza varieties have narrower leaves than Korean varieties and produce seed in the axils of branches directly along the stem. Common, Kobe, and Marion are the three identified varieties of striate lespedeza. Common is a low growing plant that is best suited for grazing. Kobe (introduced from Japan) is a larger, taller growing variety that can be grazed or cut for hay. Marion is the newest variety. It was released by the University of Arkansas and the University of Missouri and USDA. It is a good reseeder, yields well and has good disease resistance. It has slightly less upright growth than Kobe.
Korean lespedeza matures earlier than the striate varieties. Korean provides earlier grazing in summer than Kobe, but growth declines earlier in the fall. This variety does not volunteer well in south Georgia and is less tolerant of acidic soils than the Straite varieties. Rowan and Yadkin are improved varieties of Korean lespedeza. Rowan is intermediate in maturity. Yadkin matures 10 to 14 days later in fall than Rowan and has resistance to two species of root-knot nematodes.
Annual lespedeza can be sown from mid-winter until early spring. Broadcasting seed without covering normally provides adequate stands in pastures, on fallow land or in growing small grain crops. When planting in late spring on prepared seedbeds, use a grain drill or cultipacker to cover seed with about 1/4 inch of soil. For a pure stand, seed 25 to 30 pounds of inolculated, unhulled seed. When overseeding onto pastures in early spring, 10 to 15 pounds of seed per acre provides sufficient stands for reseeding to occur.
Soybeans may be used for late summer temporary grazing or harvested for hay or silage. Soybean forage has good digestibility and a medium level of crude protein. The late maturing varieties are best suited for forage uses. Other warm-season legumes that are suitable for grazing, produce high-quality forage but lack yield or persistence that make them generally unacceptable for planting in Georgia are kudzu, velvetbean, cowpeas, and Alyce clover.
The perennial cool season legumes are most productive in spring and fall. Stands usually survive for more than one year.
White Clover is one of the most widely-grown legume forage crops in the world. It is adapted to a wide range of soils and climates and is grown for forage from Florida to the northeastern United States. White clover is a low growing legume that spreads by stolons and can tolerate close grazing. It furnishes grazing in fall, late winter and spring and is widely used to overseed fescue pastures. White clover grows best on moist soils and can die during hot, dry summers. This legume is most productive on fertile soils along streams in north Georgia. In the upper Piedmont and Mountains, white clover does well on upland soils.
There are three types of white clover: large, intermediate and low growing.
Ladino, Regal, Arcadia, Tillman and Will are varieties of the large or tall growing type of white clover. They are best suited for overseeding fescue pastures in north Georgia but do not reseed as well as the other types.
There are many naturalized varieties and strains of the intermediate and low growing types such as Louisiana S1 , Nolin and Osceola. These varieties, best adapted to the lower south, are prolific reseeders and usually act as annual plants in south Georgia. Many cattlemen plant a mixture of the large growing and intermediate white clovers in pastures to take advantage of the reseeding characteristics of the intermediate clovers. The Osceola variety was developed at the University of Florida and should be well adapted to moist soils in south Georgia.
The common white Dutch clovers seen growing on roadsides and in yards are examples of the low growing type. It can be used for forage where it occurs naturally but is not planted since superior varieties are available.
Red Clover is a deep rooted, herbaceous plant comprised of many stems that rise from a central crown. The flowers are borne on heads at the tips of branches and stems and leaves are generally hairy. Red clover is a biennial. The plants flower and produce seed the second year after planting. Red clover stands generally start to thin the second year. Some stands in Georgia have persisted for several years -- perhaps because natural reseeding. Red clover is best adapted to heavy fertile soils in north Georgia and can be seeded into fescue or orchardgrass stands along with white clover. Red clover does not tolerate close continuous grazing and diseases may limit stand life during cool moist springs. Redland III, Kenstar, Cinnamon and Acclaim are good varieties for North Georgia.
Cherokee, a variety released from the University of Florida, is the first red clover developed that extends red clover's adaption to South Georgia, Alabama and north Florida. It is resistant to root-knot nematodes and is well adapted to coastal plain soils. Cherokee red clover should not be planted on droughty soils such as deep sands. It is less winter dormant and produces more spring and autumn forage than other varieties. It is less winter hardy than other varieties and is not well suited for north Georgia.
Cherokee can be used in overseeding pastures or in a mixture of small grain and ryegrass in temporary pastures. It should be seeded in the fall. Spring planting of Cherokee in south Georgia is not considered suitable for obtaining good stands.
White and red clover are best used in combination with tall fescue or orchardgrass and can be seeded in the fall or in winter (late February to early March). When seeding into fescue sods in the fall, graze or closely clip the fescue before seeding. On thick sods, some seedbed preparation is needed to thin the sod to improve stands. Herbicides may be used to retard the fescue in the fall to aid in obtaining a good stand of clover. Sod-seeding drills which cut through the sod and place the seed into the soil is the preferred method of seeding. Broadcasting and dragging seed onto a rough prepared seedbed can be successful. With late winter seedings, seed may be broadcast or drilled into a closely-grazed sod. Many farmers have had better results with late winter than with fall seedings because of better moisture conditions and fewer insect problems.
Seeding rates are 2 to 3 pounds of white clover (drill or broadcast) and 6 to 8 pounds of red clover in drill rows or 12 to 15 pounds broadcast per acre. When seeding these legumes in the same pasture, reduce the seeding rate to 2 pounds of white clover and 6 to 8 pounds of red clover per acre.
Birdsfoot Trefoil is a fine stemmed, leafy, perennial legume that resembles a fine-stemmed alfalfa. Slender stems arise from a central crown. Trefoil has a strong tap-root system. It is widely grown in the northeastern Atlantic states but very little trefoil has been successfully grown in the lower south. This situation may change in the future. Scientists with the University of Georgia College of Agricultural and Environmental Sciences are evaluating trefoil varieties that have been developed for southern conditions.
Trefoil is better adapted to acidic, poorly-drained soils than alfalfa. It tolerates close grazing and can reseed under grazing. Trefoil does not cause cattle to bloat. It should be grown only in north Georgia.
Establish trefoil on a firm, well-prepared seedbed in early fall at 5 to 6 pounds of inoculated seed per acre. Use a cultipacker-seeder and don't cover seed with no more than 1/4 inch of soil. Trefoil has poor seedling vigor and does not compete well with fescue or clover during establishment, so it should be seeded in pure stands. Fescue can be drilled into trefoil stands the year after establishment. Trefoil seeded in the fall can be grazed the following spring. Fergus and Au Dewey are the best varieties for Georgia.
Cool season annual legumes are generally seeded in the fall and provide forage in late fall and spring before flowering and producing seed in late spring. These plants die after seed is matured and do not live over the summer.
Crimson Clover furnishes some grazing in late fall and winter and abundant grazing in early spring. Crimson matures (flowers) earlier in spring than the other annual clovers and has a shorter grazing season. It grows best on well- drained soils and is frequently used in grazing mixtures with ryegrass and small grains for winter grazing. It can also be overseeded into bermudagrass and bahiagrass pastures. Crimson is a good reseeding clover when the plants are not heavily-grazed in spring. Dixie and Chief are good varieties. Tibbee is a earlier maturing variety that provides earlier grazing than Dixie or Chief. Au-Robin and Flame are varieties which flower 7 to 10 days earlier than Tibbee. Forage yields are similar or slightly better than Tibbee.
Arrowleaf Clover is a high-producing winter annual clover grown from East Texas to Georgia. It is most productive when grown on well-drained clay to sandy loam soils. It will not tolerate acid soils. This clover generally produces less forage in late fall and winter than crimson clover but will produce six to eight weeks longer in spring, and in most areas of the state will provide excellent quality grazing until late May. Digestibility remains high until maturity. Arrowleaf is a good clover to include in grazing mixtures. Its late spring production extends the grazing season and provide excellent quality forage.
Arrowleaf will reseed and can be used in warm season perennial pastures. The vigorous growth in spring can, however, reduce early spring growth of the perennial grass. In overseeded pastures, closely graze arrowIeaf clover in spring to avoid a full canopy developing over the perennial grass. Reduce stocking rates when the clover starts to flower to allow the plants to reseed.
Arrowleaf was once considered to be a good reseeder and could be used in warm season perennial pastures. In recent years though, a disease complex of Fusarium spp. and viruses have seriously reduce its productivity as a reseeder and a dependable forage.
Three varieties of arrowleaf clover are grown in the Southeast. Amclo is the earliest maturing, reaching full bloom in mid-May. Meechee blooms four to five weeks later while Yuchi is intermediate. Yuchi is the most widely-grown variety in Georgia.
Subterranean Clover (sub clover) is native to the Mediterranean and Near East and is well-adapted to areas with relatively warm moist winters and dry summers. In the United States, sub clover is widely grown in Oregon and California.
Georgia plantings indicate that sub clover is best adapted to overseeding on perennial grass pastures. It provides forage in late winter and early spring. In a stocker program, sub clover overseeded on permanent summer pastures can serve as a reserve feed source. The productive season is similar to crimson clover.
Sub clover is a good reseeding plant. After flowering and fertilization occur, a bur enveloping the seed forms and the peduncle elongates toward the ground. The stiff forked bristles of the seed bur serve as a mechanism that buries a portion of the bur in the soil, giving rise to the common name and making seed harvest difficult. The hard seed with high temperature dormancy makes the plant well adapted to reseeding. Mt. Barker is a widely-planted variety.
Berseem Clover is a non-bloating winter annual that is adapted to the southern part of the state. Stands in north Georgia are frequently frozen-out. Berseem has a longer grazing season and produces higher yields than crimson clover. This clover has a higher boron requirement than other annual clovers. Berseem is a fair to good reseeder. Bigbee is the best adapted variety. Berseem is best suited to sandy loam and loamy soils and is not tolerant to acid soils.
These winter annual clovers can be established on a prepared seedbed in combination with a small grain crop or ryegrass or they can be overseeded on summer perennial grass pastures. On prepared seedbeds, plant inoculated seed and cover with 1/4 to 1/2 inch of soil. Covering too deeply is not usually a problem when overseeding. Seeding rates in pounds per acre are: arrowleaf 6 to 8, crimson 15 to 20, and subterranean 12 to 15.
Rose Clover is native to the Mediterranean areas of Europe. Until recently, rose clover has not been adapted to the southeastern United States; however a new variety, Overton, was developed by Texas A&M in 1993. It has hairy leaves and stems and grows similar to crimson. It is winter dormant and produces forage later and flowers later than crimson. It is more drought tolerant than crimson and is more tolerant of acid soil conditions. Overton appears to be a good reseeding variety.
Hop Clover is a small, fine-stemmed winter annual that grows best on upland soils. It reseeds readily and furnishes grazing in late winter and early spring. It is usually not seeded, but volunteers in low fertility pastures. Yields are usually quite low.
Bur Clover grows in late winter and spring and re-seeds readily. Cattle do not readily graze bur clover very well when it starts to mature. The Manganese variety is superior as an early grazing crop, but does not last as long as other strains of bur clover. Bur clover produces seed in abundance and reseeds readily. The bur clovers have not been used extensively in Georgia.
Ball Clover is a reseeding legume for pastures. It has long, succulent, branching stems growing prostrate to partially upright and white to yellowish-white flower heads. Ball makes its major growth about one month later in spring than does crimson. In comparative tests, Ball clover has not produced as much total forage as crimson. It is an excellent reseeder and more tolerant of wet soils.
Vetch is usually seeded in combination with a small grain or ryegrass on a prepared seedbed for winter grazing or silage. It has a spreading, viny type growth and matures later in spring than crimson clover. Four new varieties have been released by Auburn University. Cahaba White is more cold tolerant than Vantage, Vangard or Nova II. All are resistant to root-knot nematodes. These vetches are better suited for south Georgia.
Lupine is best adapted to sandy loam and loamy sand soils in the Coastal Plain. Do not plant it north of the lower Piedmont region because it is not cold hardy. Lupine grows slowly in fall and winter, but grows very vigorously in spring. Plants will flower from late March to early April. The relatively short productive season limits lupine's use in forage programs. It is less palatable to livestock than are most legumes. Only the sweet varieties are suitable for grazing. Tifblue-78 and Tifwhite-78 are sweet varieties suitable for grazing.
Winter Peas are are frequently seeded with rye, wheat or oats for silage production. Do not plant
winter peas north of the lower Piedmont region because they are not cold hardy. Romack and
Austrian are the most widely-planted varieties. Austrian is the most winter-hardy variety.
| Table 4. Seeding Rates for Some Winter Annual Legumes | ||
| Crop | Seeding Rate (lbs/acre) | |
| Drill | Broadcast | |
| arrowleaf | 5-7 | 8-10 |
| ball | --- | 2-3 |
| berseem | 10-15 | 18-20 |
| crimson | 15-20 | 20-30 |
| hop | --- | 4-8 |
| rose | 12-15 | 15-20 |
| subterranean | 8-10 | 10-20 |
| vetch | 15-20 | 20-25 |
The symbiotic relationship that exists between legumes and rhizobia bacteria is an important biological phenomena. The rhizobia bacteria found in the nodules on the roots of healthy, legumes can absorb atmospheric nitrogen and fix it into stable amino acids that are used to build complex plant proteins. The plant supplies the energy for the bacteria to function and the bacteria makes nitrogen available for plant growth.
Legumes that are effectively nodulated can fix appreciable quantities of nitrogen. The amount of nitrogen fixed is related to crop growth rate and length of the growing season. Vigorous, rapid-growing perennial legumes such as alfalfa, fix more nitrogen than annual legumes which produce less total forage during a short growing season. Factors that negatively affect crop growth reduce nitrogen fixation. Drought, unfavorable temperatures, low soil fertility, low soil pH and poor nodulation frequently reduce legume growth.
Table 5 shows the estimated potential nitrogen function for several legumes. These values were
obtained from several sources and represent a range of the estimates reported in the literature.
They are not absolute values and will vary with conditions that affect legume crop growth.
| Table 5. Estimated Nitrogen Fixing Potential of Several Leguminous Crops | |
| Legume | Amount of Nitrogen fixed/acre (lbs) |
| Alfalfa | 175-300 |
| Ladino clover | 175-300 |
| Blue lupine | 75-150 |
| Crimson clover | 75-150 |
| Arrowleaf clover | 75-150 |
| Vetch | 75-150 |
| Lespedeza | 75-150 |
| Winter peas | 75-150 |
Before symbiotic nitrogen fixation can occur, legume roots must be nodulated by the proper species of rhizobia bacteria which are not native to our soils. The bacteria can be added to the seed at planting to ensure that nodulation will occur.
Commercial sources of inoculant are available to inoculate the various crop and forage legumes.
It is important to use the correct inoculant. Legumes are grouped for the purpose of inoculant
identification (See Table 6).
| Table 6. Grouping of Legumes by Inoculant Type | |
| Inoculant Type | Crops |
| Alfalfa | alfalfa, bur clover, sweet clover |
| Clover | crimson, hop, red, white, ladino |
| Lupine | blue, yellow, white |
| Pea and Vetch | field pea, Austrian winter pea, vetch |
| Cowpea | cowpea, lespedeza, beggarweed, kudzu, peanut, velvetbean |
| Arrowleaf clover | special type 0 inoculant |
| Rose clover | specific inoculant |
| Subterranean clover | specific inoculant |
Inoculate seed with fresh inoculant just before seeding. The inoculants are usually packaged in plastic bags to protect the bacteria from drying. One 8-ounce bag of most inoculants will inoculate 50 pounds of seed. Read the label and follow instructions.
To inoculate, fill a large metal or plastic tub about half full with seed and apply enough water to moisten the seed (you will need to stir the seed). Sprinkle the right amount of inoculant on the moist seed and stir until the seed are uniformly coated. Moist seed tend to stick together, so let the seed dry for a few minutes before seeding.
The inoculant sticks to the seed better if a water-sugar solution or syrup-water solution is used to moisten the seed. Recent research indicates that a commercial sticker material significantly improves inoculation. Protect the packages of inoculant from direct sunlight or hot temperatures.
Some companies market pre-inoculated legume seed that have been coated with an inert material, usually lime, to protect the inoculant. No further inoculation is required before planting unless the seed has been stored past the expiration date listed on the label.
The nitrogen fixed by legumes is used for vegetative growth and reproduction and is not directly available for grasses growing with legumes. Approximately 80 percent of the nitrogen fixed is found in the above ground parts of the plants. The associated grass does benefit, however. As the legume grows, some roots and nodules die and decay. At the end of the growing season of annual legumes, the entire root system dies, adding organic nitrogen to the system. Legume forage not consumed by livestock or cut for hay also serves as a source of organic nitrogen.
Another source of nitrogen for grasses is nutrient recyling after the legume forage has been grazed by cattle. More than 85 percent of the nitrogen and potassium in forages consumed by cattle is excreted in feces and urine and is added back to the soil.
Pasture plants are best established on fertile, well-prepared seedbeds. The amount of tillage necessary to prepare a good seedbed depends on what crop was last grown on the site. When converting cropland into pasture, less tillage is needed than when establishing new pastures on soils formerly in weeds and brush, or old sods of native grasses. Two or three plowings and diskings might be needed for soil preparation. When tilling pasture sites, consider the erosion potential and try to minimize erosion in new pastures. Most pasture seed is small; therefore, a firm, moist seedbed is essential to obtain a good stand.
A good liming and fertilization program helps to establish and maintain productive pastures. Soil pH and fertility status of soils varies because of past fertilization and liming practices. A soil test taken several weeks before preparing the seedbed helps determine the lime and fertilizer elements needed. .
Lime supplies calcium and magnesium and neutralizes soil acidity (increase soil pH). It also promotes desirable bacterial activity in the soil, improves organic matter decomposition and increases the plant's ability to efficiently use fertilizer elements. Most crops grow well at a pH of about 6.0. Alfalfa requires a higher soil pH (6.5 to 7.0). Apply limestone uniformly before the soil is prepared and work it into the top 6 inches of soil. It is very important to incorporate lime when establishing pastures because all subsequent applications will be surface applied and cannot be incorporated. Use dolomitic limestone (because it contains magnesium) when soil test results show low soil magnesium levels.
Proper fertilization promotes rapid early growth and helps ensure good stands. Apply and incorporate phosphorus (P205) and potassium (K2O) as indicated by soil test results before planting. Incorporation is necessary for phosphorus because the element is not mobile (does not leach) in the soil. Rates vary depending on native soil fertility and the crop that is being established.
Nitrogen is necessary for rapid early growth of seedling grasses. Apply 30 to 60 pounds of N per acre before seeding or soon after the seedlings start to grow. Additional N may be needed later in the growing season.
Most forage plants (except the hybrid bermudagrasses) are established from seed. When purchasing seed, buy weed-free seed of known origin. Certified seed is a good buy. When establishing the hybrid bermudagrasses, good sprigs are important. Dig sprigs from fields that are pure and have few weeds.
Legume plants (when nodulated by the proper strain of rhizobia bacteria) can fix atmospheric nitrogen into a form that the plants can use for growth. The bacteria necessary for nodulation do not occur naturally in Georgia soils and must be applied to the seed at planting.
Crops established from seed can be planted several ways. It is important to get the seed into the soil at a uniform depth and firm the soil around the seed. Do not plant seed too deeply. Plant large-seeded crops such as rye or wheat 1 to 1-1/2 inches deep. Cover small seeded crops such as ryegrass, clovers or alfalfa with 1/4 to 1/2 inch of soil.
Grain drills are good seeding implements and can be equipped with a small seed attachment to accurately seed small-seeded clovers. Sod seeding drills are equipped with a disk coulter that slices through sods for planting established sods. Cultipacker seeders are well suited for seeding small seeded legumes, such as alfalfa, on well-prepared seedbeds. An alternative method is to broadcast seed and incorporate by disking. Broadcasting seed and disking is less precise so increase the seeding rate by 25 percent.
Warm season perennial forage crops such as bermudagrass, bahiagrass and dallisgrass supply forage for five to six months. Overseeding these pastures with winter annuals provides an additional 75 to 100 days of high quality grazing in late winter and spring.
Fall overseeding does not provide fall and early winter grazing. The quantity of forage produced increases rapidly in mid-winter and early spring. Forage production from winter annuals continues until the summer grasses begin growth. Summer grass growth can be delayed if a dense growth of the winter annual accumulates in late spring. If surplus forage occurs, harvest it for hay to permit near- normal development of the summer grasses.
Overseeded crops are usually more successful and require less land preparation when planted on sods of bermudagrass and dallisgrass rather than on bahiagrass. Overseeding is not always successful. Most failures are caused by failure to remove excess growth of the summer crop before seeding winter annuals, failure to get seed of the overseeded crop in contact with the soil and lack of adequate plant nutrients.
Use any of the adapted annual cool season grasses or legumes for overseeding. Ryegrass and annual clovers (crimson, subterranean and arrowleaf) are well suited for overseeding with minimum seedbed preparation. Use rye, wheat and oats alone or in a seed mixture with ryegrass and clovers. More land preparation is required when small grains are used for overseeding.
Overseed in the fall when cooler temperatures have slowed the growth of the summer grasses (about October 15 through November 15). Seeding too early, when the summer grass is still rapidly growing, usually results in poor stands. Actively-growing summer grasses provide too much competition for the new seedlings.
For overseeding to be successful, the seed must be placed into the soil (or in contact with the soil) and the soil firmed around the seed. Established bermudagrass or bahiagrass stands that have a large amount of surface thatch are difficult to seed into. In these cases, seedbed preparation will result in better stands and faster early growth of the overseeded crop. Bahiagrass offers more competition to new seedlings than bermuda and could require more seedbed preparation. Two passes with a tandem disk set for shallow penetration should be sufficient preparation. Extensive disking in the fall can cause some stand loss in hybrid bermudagrass pastures.
Grain drills, sod seeding drills or broadcast seeders may be used for planting. The new sod seeding drills can place seed into the soil, even in thick sods, and offer an alternative to land preparation. When seed are broadcast on disked sods, use a drag to cover the seed and smooth the surface.
A good fertilization program is necessary for high yields of good quality forage and to maintain healthy productive stands of grasses and legumes. Rates and types of fertilizer vary with crops, intensity of management and native soil fertility. Soil testing is a valuable tool when developing a good pasture fertilization program.
Soil pH is a measure of soil acidity. When soils are too acid (pH is too low) crop growth will be reduced. On the other hand, soils become too basic by over-liming (pH over 7.0) which has a detrimental effect on plant growth. Overliming is seldom the case in Georgia. Most crops grow best when the soil pH is about 6.0. Alfalfa requires a higher soil pH (6.5 to 7.0).
Most Georgia soils are acid and require liming to increase soil pH and to supply calcium and magnesium. Common liming materials, calcitic and dolomitic limestone, contain calcium. Dolomitic also contains magnesium and should be used when the soil magnesium level is low.
Soil pH is reduced when ammonium forms of nitrogen are applied. Heavily-fertilized hay or silage fields require more frequent applications of lime than grazed pastures to neutralize the acidity resulting from high rates of ammonium forms of nitrogen.
Forage crops, like other crops, need at least 13 mineral elements for normal growth and reproduction. These elements are grouped into three categories based on the concentration found in the plant. The major elements (nitrogen (N), phosphorus (P2O5) and potassium (K2O) ) are required in greater quantities than the secondary elements (calcium (Ca), magnesium (Mg) and sulfur (S) ) or the micro-nutrients (boron (B) , copper (Cu), manganese (Mn), zinc (Zn), iron (Fe), molybdenum (Mo) and chlorine (Cl) ). Plants get these elements from the soil. Georgia soils do not contain sufficient concentrations of some of the elements to meet the plant's need for rapid growth and supplemental fertilizer must be applied.
Nitrogen is necessary for rapid growth and influences plant protein content. The amount of fertilizer needed and the correct timing of applications varies with crops and how the crops are used (for grazing or hay). More nitrogen can be effectively used for hay production than for pastures that are grazed.
Phosphorus is an essential plant element that plays a key role in many vital plant processes such as root development. Low soil levels of phosphorus can cause difficulties in establishing new pastures. This element does not leach from the soil and one application per year is sufficient.
Potassium is essential for producing economical yields. Potassium is second only to nitrogen in the concentration found in plants. It affects plant vigor, disease resistance, forage quality, winter survival and stand life. Prevent potassium deficiencies through a good fertilization program. Multiple applications are more efficiently used by plants and ensure an adequate supply of potassium throughout the growing season. This is particularly important with alfalfa and bermudagrass harvested for hay. Two to three applications per growing season are advisable for these crops. Potassium is a mobile element and will leach from sandy Coastal Plain soils.
Boron is needed in very small quantities by plants. In Georgia, it is necessary for alfalfa and clovers that are grown for seed. Boron may be mixed with other fertilizer materials and applied in the spring.
Sulfur is needed by plants that accumulate high levels of nitrogen in their tissues. In Georgia, yields have increased for sulfur applications. Deficiencies have occurred recently because of a shift to the use of high analysis phosphate fertilizers which contain only small quantities of sulfur. Sandy soils are more likely to be deficient in sulfur than heavier soils. Sulfur can be deficient on soils containing little organic matter or where such factors as drought or low pH cause decomposition of the organic matter to be slow.
Molybdenum is required by legumes for nodulation and nitrogen fixation. Molybdenum deficient legumes are stunted, the plants may become yellow and the lower leaves can die and drop prematurely. Use molybdenum on alfalfa and soybeans.
Calcium deficiencies are rare if the soil pH is about 6.0. Legumes accumulate higher levels of calcium than grasses. A good liming program prevents deficiencies.
Magnesium deficiency causes yellowing between the leaves and is found on acid sandy soils and soils low in magnesium. Use dolomitic limestone to increase soil magnesium and reduce deficiencies. Additional magnesium applications might be required for alfalfa and irrigated corn.
Manganese deficiencies (rare in forage crops in Georgia) can be caused by poor drainage or high soil pH. Deficiencies may occur in depressions or poorly-drained areas where the soil pH is higher than the surrounding areas. Manganese problems have been observed on small grains and soybeans grown on poorly-drained soils in southeast Georgia when the soil pH was over 7.0. Leaves of deficient plants show a mottled yellowing between the veins, similar to iron or magnesium deficiencies, but the veins never turn yellow.
Zinc deficiencies are more likely to occur on coarsely-textured soils in the Coastal Plain than on the heavier soils in the Piedmont and Mountain regions. Zinc has not been a significant problem with forage crops.
Hybrid Bermudagrasses will produce high hay yields when well fertilized and moisture is not limited. Apply 80 to 100 pounds of nitrogen per acre in spring before growth starts and 60 to 100 pounds of N after each cutting except the last cutting in the fall. Rates of P and K needed vary with soil fertility and the rate of N used.
When the bermudagrasses are grazed, use lower N rates (150 to 200 pounds per acre) during the grazing season. Apply in two or more applications. Splitting N applications improves utilization and levels out forage production.
Bahiagrass and Dallisgrass produce lower yields than bermudagrass and are usually grazed rather than cut for hay. Apply 100 to 200 pounds of N in split applications during the grazing season. Base the N rate on the quantity of forage needed.
Fescue-Orchardgrass grown in pure stands can use 100 to 150 pounds of N per acre. When producing hay, apply 60 to 80 pounds of N in late winter (February to early March). Fescue can be fertilized with N (40 to 60 lbs/A) in the fall (September) and forage produced for deferred grazing in early winter. Apply P and K as indicated by soil test.
Fescue/Clover and Orchardgrass/Clover. When pastures contain a good stand of white or red clover, use lower rates of N. When the clover constitutes 20 to 30 percent of the stand, apply 20 to 40 pounds of N per acre in spring. When more clover is present do not apply any N. Be sure to apply adequate P and K.
Winter Annual Grasses (Rye, Ryegrass, Wheat, Oats). Use up to 150 pounds of N per acre. Apply 40 to 60 pounds of N in fall at planting or when the seedlings start to grow. A second N application of 60 to 80 pounds per acre in early winter will produce grazing in late winter and spring. Ryegrass grows longer into the spring than the small grains and can use an additional N application of 40 to 60 pounds in late March or early April.
Winter Annual Clovers (Arrowleaf, Crimson, Rose, Berseem and Subterranean). Like other legumes, fix atmospheric nitrogen into a form that they can use for growth and do not require applied N. They do, however, require good soil fertility. Apply P and K as indicated by soil test results. When producing seed, 1 to 2 pounds of boron per acre can be beneficial.
Perennial Legumes (White Clover, Red Clover) are most frequently grown with fescue in north Georgia. The clovers will produce more forage and survive longer with good P and K nutrition. Apply fertilizer in either spring or fall. In most cases, fall applications will improve winter survival.
Alfalfa and Perennial Peanuts, a high-yielding perennial legume, can be grown on well-drained soils throughout the state. Alfalfa must be well fertilized to produce high yields and to keep stands healthy. A typical fertilization program for high-yielding alfalfa consists of: Phosphorus (P205), 70 to 100 pounds per acre; Potassium (K2O), 200 to 300 pounds per acre; Sulfur, 10 to 30 pounds per acre and Boron, 3 pounds per acre. Molybdenum applied every other year (1/2 lb/A) improves nodulation and nitrogen fixation. Potassium is used more efficiently on sandy soils when split applications are made. In south Georgia, make three to four applications during the growing season. Two to three applications per year are sufficient in the Piedmont and Mountains. Perennial peanuts are best suited to south Georgia.
Animal performance is improved when pastures are closely grazed. The forage in closely-grazed pastures is younger, has a higher leaf content, higher protein level and is more digestible than forage in undergrazed pastures where excess forage accumulates and matures.
There is a major difference between close grazing and overgrazing. When pastures are overgrazed and forage availability is limited, animal performance declines because of reduced intake. A closely-grazed pasture can become an overgrazed pasture very quickly if forage growth slows and the stocking rate is not reduced. Most cattlemen tend to operate on the safe side and allow some forage to accumulate as a buffer against periods of reduced forage growth.
How close pastures can and should be grazed varies with species. Perennial pastures, such as bermudagrass, bahiagrass and endophyte-infected tall fescue, will tolerate close grazing (2 to 4 inch stubble height) and maintain good stands. Do not closely graze orchardgrass and endophyte-free tall fescue in the summer when the plants are under moisture or temperature induced stress. Maintain at least 4 inches of growth in these pastures.
Pastures can be grazed continuously or rotationally. With continuous grazing, the cattle stay on the same pasture for extended periods, perhaps for the entire season. In rotational grazing, the cattle are moved from pasture to pasture during the grazing season.
A continuous grazing program requires less fencing to subdivide large pastures and less labor to handle cattle. The major disadvantage of continuous grazing is the difficulty in matching the stocking rate to the forage growth rate. During rapid growth, the supply of forage exceeds demand and excess forage accumulates. Because young forage is more digestible and palatable than older forage, the cattle start to "spot graze." Some areas of the pasture will be grazed heavily while the forage in ungrazed areas grows and matures. When conditions are not favorable for forage growth the pasture might not be able to supply enough forage for cattle. Overgrazing occurs and cattle lose weight unless supplemental feed is provided.
With rotational grazing, large pastures are fenced into smaller units. Cattle are confined in one area until the forage is grazed to the desired stubble height. The cattle are then moved to the next area and the process is repeated. The length of the grazing period in each area depends on stocking rate and forage growth rate. When conditions are favorable for rapid forage growth it is not necessary to graze each of the grazing areas or paddocks. Harvest and store the forage in areas not needed for grazing during the winter. When forage growth is slowed by dry weather or other conditions, all of the grazing areas might be needed to meet the forage demand. Rotational grazing provides flexibility and allows more efficient utilization of the forage that is produced.
Most Georgia cattlemen continuously graze pastures or use a modified rotational grazing system. Forage utilization could improve with rotational grazing. However, for most operations the returns do not justify the additional fencing required to subdivide pastures into smaller units. Supplying water for the cattle can be a problem when pastures are subdivided. Rotational grazing is profitable for intensively-managed cattle operations.
Top grazing is a management concept that can be effectively used in rotational grazing programs. Cattle select the highest quality forage available before grazing lower quality forage. Place cattle that have high nutrient requirements (yearling cattle or replacement heifers) on pastures for a few days before other cattle are allowed to graze. The first animals to graze will select the highest quality forage and perform better than if grazed along with older cattle. Continue rotating the younger cattle or other animals that require higher quality forage onto pastures before the bulk of the herd grazes the pasture.
Intensive grazing programs are not suitable for all situations but are effective for many intensively-managed operations.
Weeds can be serious problems in forage crops. They compete with crops for light, nutrients and water and can reduce forage production and lower forage quality.
Weeds are less severe when pastures are well-managed. A vigorous, healthy grass sod provides good competition for most weeds.
Herbicides can be used to control weeds in pastures. Your county extension office will have publications to help you in this area.
Pasture management influences forage quality, yields and the useful life of the pasture. The following recommendations are provided as a guide to keep pastures productive.
For more specific information on forage crop production and utilization refer to the following Cooperative Extension Service publications: Bulletin 911, Bermudagrasses in Georgia; Circular 633, Renovating Fescue Sods; Circular 676, Tall Fescue; Circular 645, Winter Annual Forage Crops; Bulletin 898, Alfalfa in Georgia, Bulletin 716, Silage Production, Harvesting and Storing; Leaflet 244, Overseeding with Winter Annuals; and Leaflet 172, Arrowleaf Clovers.
A highly recommended source of information on forages is the book, Southern Forage. The second edition is available from the Potash & Phosphate Institute and the Foundation for Agronomic Research at 655 Engineering Dr., Suite 110, Norcross, GA 30092-2843.
Bulletin 573/Revised July, 1997
The University of Georgia and Ft. Valley State College, the U.S. Department of Agriculture and counties of the state cooperating. The Cooperative Extension Service offers educational programs, assistance and materials to all people without regard to race, color, national origin, age, sex or disability.
An Equal Opportunity/Affirmative Action organization committed to a diverse work force.
Issued in furtherance of Cooperative Extension work, Acts of May 8 and June 30, 1914, The University of Georgia College of Agricultural and Environmental Sciences and the U.S. Department of Agriculture cooperating.
Gale A. Buchanan, Dean and Director
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