Two of this large genus are used as pasture and hay crops, namely birdsfoot trefoil (L. corniculatus) and greater trefoil (L. uliginosus (syn. L. major, L. pedunculatus of authors)). They are fine-leafed, stemmy perennials with sessile leaves and showy flowers. Their pods are long and narrow. Trefoils are interesting for soils low in phosphate, in places where fertilizer is dear or difficult to transport.
A native of temperate Europe and Asia, it is used for pasture and sometimes hay. It is a hardy perennial with a strong tap root, procumbent stems and yellow or red flowers. It is also grown in North America, Australia, New Zealand and South America. It is more tolerant of poor soil, waterlogging, salinity (cf the case study on Altai) and high temperatures than the more important temperate clovers, but does not compete well with clover and lucerne where conditions suit them.
Cultivation is as for clover; the seed rate is 5 to 7 kg/ha in pure stand, but much less in mixtures. It is slow to establish compared to clover and is not suited to short rotation use. Seedling vigour is much less than that of lucerne or red clover and establishing stands can be lost through shading by competing crops or weeds. USA practice is reviewed in detail by Seany and Henson (1970), who recommend that hay fields should be managed to avoid very early or late autumn cuts. Birdsfoot trefoil is very prone to lodging as it approaches maturity, with consequent losses during mowing and curing hay; this is reduced if it is associated with cocksfoot or timothy. Viking is a popular cultivar in Canada, together with Empire, Leo and Maitland. It is usually mown for hay as the plants come into bloom. Potential seed yield is probably 600 - 1000 kg/ha, but harvest is not easy since the pods shatter explosively when ripe: field yields may be as low as 50 - 150 kg/ha.
Lotus uliginosus (syn L. major and L. pedunculatus of authors)
Greater or big trefoil resembles L. corniculatus and is used in the same way, but is much less winter hardy, does not withstand salinity or drought, and needs more moisture. It is grown on low, wet land, and in high rainfall areas of Europe, North America and New Zealand; it is naturalized and well established in the wet, temperate Andes. The New Zealand cultivar Maku has been used with success for pasture improvement on poor soils in wet conditions.
Lucerne or alfalfa is an upright, deep-rooted perennial with many, usually erect, stems which arise from crown buds. It is the world's most important forage crop and a high-quality feed for all types of livestock. Under suitable conditions, it is the most productive fodder legume, and probably the first fodder to be cultivated. It was grown in Iran in 700 BC, reaching Greece 200 years later. It spread throughout southern Europe, North Africa and Asia, and was taken to the Americas by the Spaniards, and later spread to the USA in the mid-nineteenth century. Lucerne reached China in the second century BC, when Iranian horses were acquired for military use. It only came into use in northern Europe and Australasia during the past two centuries. It is a common small-scale farming crop in the drier parts of Asia and North Africa; in some areas, the young shoots are traditionally used as a vegetable. Lucerne is noted as a soil improver, in both small-scale and large-scale farming. It is highly melliferous, and because of its many flowerings throughout the year, is of great potential interest to beekeepers. For warm, arid and semi-arid areas, a full treatment is given in the FAO publication by V.L. Marble (FAO, 1989).
It is a crop which requires low humidity and neutral-to-alkaline, well-drained soils, but can be grown on moderately acid ones. It does not, however, tolerate humid climates at high temperatures; its poor performance in humid, tropical and subtropical sites on acid soils has often been proven. Cultivars are available to suit conditions from the dry subtropics to the coldest limits of agriculture. For rainfed cultivation, a minimum of 500 mm per year of precipitation is required in subtropical regions, but in colder zones it can be grown on 300 mm. High rainfalls, over 800 - 1 000 mm, unless on very well drained, deep soils, are less suitable. Above 1 000 mm, soils are usually more acid and humidity greater, leading to more leaf disease, and there is danger of periodic waterlogging. Good, well-drained land with a deep root-run should be chosen to sow lucerne for hay, as rooting depth can be 3 to 5 m if moisture is not limiting.
Two main subspecies of Medicago are involved in the development of the wide range of lucerne cultivars now available: the purple-flowered M. sativa subsp. sativa is the standard form, and yellow-flowered M. sativa subsp. falcata (sickle-pod lucerne) which is rhizomatous and frost and drought resistant. M. sativa grows in more clement climates, south to the Mediterranean region. Where the distribution of the two forms overlap, hybrid forms arise, formerly identified as M. media or M. varia, but now known as M. sativa subsp. varia.
Cultivars may be classified into four groups according to origin and hardiness:
The Common group comprises pure M. sativa subsp. sativa types, with purple flowers and limited winter-hardiness. It is represented by the common lucernes of the USA and regional strains from central Europe, Argentina, South Africa, New Zealand and Australia.
The Turkistan group consists of M. sativa subsp. sativa types. Their growth habit is shorter and more spreading than the Common group. It has slow recovery after cutting, with low seed yield, but is resistant to cold and bacterial wilt.
The variegated group of cultivars, which have variegated flower colour and probably originated as hybrids between M. sativa subsp. falcata and M. sativa subsp. sativa. Most are winter-hardy.
The non-hardy group that is adapted to short days and a long growing season, and characterized by erect growth, rapid recovery after cutting, susceptibility to cold injury, bacterial wilt and leaf diseases. Representative strains occur in many warm, lucerne-growing countries: Egypt, west Asia, North Africa, India, Peru, and some Argentinean and Chilean strains.
Many local ecotypes exist throughout the traditional lucerne-growing areas, and these are often well adapted to local conditions and management practices. For example, much of the lucerne in the Near East is cut very low by sickle and often on a shorter cycle than is usual elsewhere. Unfortunately, local seed is usually expensive, scarce, dirty and of poor quality, with severe weed contamination. Cuscuta spp. (dodder; a parasitic plant) is a most serious weed and is a common contaminant in bazaar seed. Imported cultivars are not necessarily better than local landraces: Marble (FAO, 1989) presents data showing that local Near East varieties were as good as or better than imported varieties in a seventeen-cut trial in Saudi Arabia. A trial in Xinjiang-Altai of very cold-tolerant lucernes from other areas (mostly North America) showed very superior growth of the exotics during the establishment year, but all were dead next spring - only the local varieties survived the severe, snow-free winter. Although some countries in western Asia and North Africa have seed certification facilities, there is still a lot of room in the traditional areas for: (i) evaluation of local material; (ii) cleaning up the seed supply; and (iii) organizing marketing.
Since lucerne is grown in so many ways and places, installation methods vary and must be adapted to local realities. The remarks here are specific to crops for cutting. Lucerne can be included in semi-arid pastures, often at very low seed rates, but that is not our concern here. For hay production, land preparation should be thorough and deep. Where there is any possibility of hard pans or impermeable layers, especially for irrigated crops, sub-soiling or chisel-ploughing can be very beneficial. Seed should always be examined for the presence of dodder (Cuscuta spp.) seed if obtained from a non-certified source; samples containing even traces of dodder should be rejected. Rotation of lucerne with other crops is advisable; it should not be re-seeded immediately after ploughing out another lucerne crop, as, apart from the usual reasons of pest and disease control, there is a problem of autotoxicity which suppresses establishment (e.g., Jennings and Nelson, 1998) although the effect is usually short-lived and can probably be leached out by irrigation water.
Inoculation with the appropriate strain of Rhizobium is recommended on all newly-broken land, on fields which have not borne lucerne for several years and on all fields where the pH is less than 6.2. Suitable inoculants are widely available commercially. Lucerne seed of high quality is readily available on the world market. As noted above, however, there is often a scarcity of clean high-quality seed of locally adapted cultivars and landraces; a striking example is given in the Altai case study.
Lucerne is a cross-fertilized autotetraploid; its flowers must be tripped and cross-pollinated by bees if high seed yields are to be attained. Wild bees will trip lucerne, but it is advisable to place hives of honeybees near large seed fields to ensure pollination. Seed can be produced from fields close-planted for hay but, for specialized seed production, wider row-plantings usually give superior yields. In order to attain high seed yields it is essential that the plant has stored adequate energy in its roots; this is far easier to attain with spaced plants than in the dense swards desirable for hay or grazing, which are mown several times in a season. Row-planted lucerne gives better access to bees, light penetration and less humid conditions within the crop canopy. Row spacing depends on local conditions, with 90 cm a useful starting point. Seed rates should be low, 2 to 5 kg/ha, and thinning plants in the row may be beneficial. Weeding is very necessary in newly sown stands, to improve seedling survival and growth and to remove undesirable contaminants.
Seed stands should not be mown or grazed before first harvest, unless a cut is necessary for weed control. Established stands should be mown in spring prior to the development of the seed crop; depending on local conditions, several hay cuts may be taken before the seed crop, which must be so timed as to flower and ripen under favourable conditions. The seed crop may be cured and prepared for harvest by: (i) hand stripping, drying and threshing pods; (ii) mowing, windrowing, curing and threshing with a combine; or (iii) spraying with a desiccant, followed by direct combining of the dry standing crop. The last method is commonly used in intensive seed production, the first under small-scale farming conditions.
For irrigated lucerne, seed-bed preparation and land levelling must be done with the greatest care; any local variations in level which cause surface accumulations of water, even temporarily, predispose toward crown diseases. A firm, clean, seedbed, free from large clods, is necessary, and tillage operations should be designed to this end. All perennial grasses and weeds must be destroyed before the crop is installed; Cynodon dactylon is a serious pest in warm climates. Fertilizer is essential and rates should be determined by local trial and experience; phosphorus (P) is the most important nutrient; sulphur (S) and potassium (K) may be locally important. Nitrogen is never required for properly nodulated lucerne and should not be used at any time. Occasionally, micronutrient deficiencies occur. Fertilizer should be applied immediately before sowing and worked into the top 1.5 cm of the soil. Where there is a serious P deficiency, a heavy basal dressing (80 - 100 kg/ha P) should be ploughed in.
The timing of sowing will have to be decided in the light of local conditions and experience; in areas with a rainy season, it may be possible to establish on rain and irrigate thereafter. High seed rates, 25 to 30 kg/ha are often used under flood irrigation, broadcast or close-drilled. Where small-scale farmers save seed of local ecotypes, excessively high rates, up to 80 kg/ha, are used, but this probably reflects the poor quality and low germination of that seed. Flood-irrigated fields should be watered a few days before sowing so that the seed germinates on residual moisture and only a light first irrigation need be given. On very light soils, however, it may be necessary to irrigate immediately after sowing. Under small-scale farming conditions, hand-drills worked by two people have proved very efficient and economical of seed. Where overhead irrigation is available, lower seed rates (15 to 20 kg/ha) are used. A seed depth of 0.5 to 1 cm should be aimed at; seed sown deeper than 2.5 cm will have very poor emergence. Where there is danger of high winds or sandstorms at emergence, it is advantageous to use a light seeding of a nurse crop (such as barley, oats or wheat), sown immediately before the lucerne, which is cross-drilled over it.
Weeds are a problem at establishment, except on some newly-broken land. They must be controlled early. On very small areas, weeding may be possible, otherwise control can be through cutting or herbicides. Cutting early is cheaper but less effective, and may weaken the stand; young plants should not be cut before there are two to four stems on each crown, but if they are being stifled by weeds an earlier mowing may be necessary. Pre-planting and selective herbicides are available and should be used according to the manufacturers' instructions.
For rainfed lucerne, again, a clean, fine and firm seed-bed is required. Seed rates are generally lower (5 to 10 kg/ha). Sowing must coincide with rainfall and autumn sowing must allow sufficient time for the plants to become well established before winter. The seed must be firmed in the soil, so drills with press-wheels are preferred. Broadcast seed should be rolled, with a ring-roller if possible. Fertilizer is necessary and rates should be judged by local conditions. In some cold areas with snow, lucerne can be established by sowing before snowfall, to germinate after the thaw.
Lucerne is the hay crop par excellence and has been so used since the beginning of its cultivation. However, as its growing points and growth habit differ from the more usual hay plants, which are grasses, and since multiple cuts are taken annually in all except the coldest parts of its range, care is required in both the timing and the height of cutting. The main source of loss is usually leaf shattering during handling and baling. Small-scale farm haymaking techniques often take this into account, employing methods such as rolling into small bundles after wilting and then drying, or drying at the homestead and sweeping up fallen leaves. For mechanized conditions, Frame, Charlton and Laidlaw (1998) quote the Pennsylvania State University Extension Service recommendations for minimizing forage loss and good conservation practice, as including:
- mowing when there is little chance of rain, but be ready to take risks to avoid slippage of the cutting schedule;
- laying the cut herbage in as wide a swathe as possible to aid drying;
- "raking" at 60% DM, as slowly and as few times as possible; and
- baling at about 82% DM, so that the hay is not too dry, which would result in leaf-shatter during raking, or too wet, which would lead to high in-store losses.
As a general rule, lucerne should be mown at 25% - 50% flowering. After each cutting, lucerne, as a perennial, must recover and try to produce another crop; the energy for new shoot, leaf and feeder root production comes from carbohydrate stored in the root system until such time as the plant can once again photosynthesise sufficient energy for its needs. Root-reserve depletion continues until re-growth is 20 - 25 cm in height and the ground is almost fully covered by leaves. It is, therefore, of the utmost importance that the growth stage of the plant at mowing (and therefore the cutting frequency) be chosen to ensure both optimum re-growth and yield. This is related to elongation of basal crown shoots: at the 25% - 50% bloom (not 25% - 50% bud!) stage, 80% of the crowns should have basal shoots between 35 and 50 mm long for this to be a suitable cutting time. To ensure that the lucerne can compete with weeds, a full leaf canopy covering the whole soil surface must develop a few days after cutting; early cutting reduces plant vigour, encourages weed invasion, reduces yield and shortens the life of the stand. Leaving the crop after 50% flowering lowers the number of cuts possible and, hence, annual output; it will also reduce hay quality. Often in small-scale farming practice the field is not cut all at once, as some is cut daily to fit in with other tasks, so exact timing by growth stage is not always possible. In very cold areas, the last cutting should be sufficiently ahead of the first frosts to allow some re-growth to strengthen the root system; this can be grazed off once killed by frost.
Height of mowing
A stubble of 5 to 10 cm should be left to avoid damage to the young basal shoots, which provide the re-growth. This is not a problem with mechanized mowing, but hand-cutting, especially with a blunt sickle, is frequently done at ground level and causes considerable damage to growing points. Cutting height is an essential subject in small-scale-farming extension.
Maintenance and management
Lucerne does not tolerate continuous grazing for prolonged periods. In general, a five-week rest between grazings is optimal. Cutting regimes have been discussed above. Fertilizer application will depend on local soil conditions. Nitrogen is not required by correctly-nodulated stands, but phosphorus and potassium will probably have to be supplied annually to high-yielding, irrigated crops. A phosphorus content of below 0.18% for the whole top would indicate a probable response to applied P. A value of 1% K in the top indicates a need for K fertilizer. A dressing should be made late in the season, with 100 kg/ha of phosphorus and 300 - 500 kg/ha of potassium. Weed control may be necessary. Herbicides can be used for some weeds, while for mechanical cleaning and cultivation of established stands, narrow-pointed "lucerne tines," which pass between the crowns without uprooting them, can be used.
The dodders (Cuscuta spp.) are by far the most serious weed of lucerne. They may come in as seed contaminants, through irrigation water, dung from grazing stock, or by other mechanical means of transmission; stock fed on infested hay must not graze on lucerne fields. Once a field is infested, dodder seed will continue to germinate for many years. Seriously infested fields should be taken out of lucerne and cropped to cereals; clovers are alternate hosts. Dodders are parasitic and the seedlings must attach themself to a lucerne plant within 20 - 30 hours of germination. Some degree of control can be attained by hand-cutting affected patches, by using burners or contact herbicides like Paraquat (GramoxoneÒ); the parasite and the lucerne stems should be destroyed to ground level. Treatment must be before the dodder has set seed.
A cold and drought tolerant, creeping-rooted perennial, found over a wide range of harsh environments, including far into Siberia, Mongolia and the higher zones of the Himalayas, and as far south as North Africa. It is grown on a limited scale, but seed is difficult to harvest because of shattering pods. It is an important spontaneous fodder in many areas, including Nepal.
"Variegated" group of lucernes
This name is sometimes used for lucernes developed from hybrids (M. sativa subsp. ´ varia (syn. M. media)) of M. sativa and M. falcata, and corresponds to the "variegated" group of lucernes. Cultivars such as Provence, Grimm and Ladak belong to this group.
Annual lucernes or "medics"
Several annual medicagos are important in the natural vegetation of the wheat-fallow rotations of the Mediterranean region, and some have been domesticated and widely sown in Australia, usually as self-re-seeding annuals in semi-extensive cereal-fallow-grazing systems. Most are suited to grazing, but some more erect species, such as M. orbicularis and M. scutellata, can be mown for hay.
Several species of Melilotus have long been cultivated for grazing, as fodders and as green manures. They are erect annuals or biennials, which smell strongly of coumarin (found in all parts of the plant), with a growth habit somewhat similar to lucerne, and trifoliate leaves with long leaflets. Poorly made hay or silage may be toxic to animals since a coumarin breakdown product causes internal bleeding. The seed of sweet clovers survives for years in the soil, so if a crop is allowed to seed before mowing or ploughing-in, sweet clover will come up as a weed for a long time.
The indigenous Melilotus spp. of North Africa have similar agronomic needs to medics (annual Medicago spp.) in wheat-fallow rotations, but Melilotus spp. seed more freely, are less palatable and have a lot of hard seed; sometimes they take over from and shade out medics and are difficult to eradicate. They can, of course, be left to grow tall and cut as hay.
Sweet clover is used in North America as fodder and green manure. It is also grown in northern China for soil improvement and fodder, as an over-wintering catch crop sown after wheat and harvested in spring, then ploughed in before a summer crop; it may be undersown in winter wheat.
It is widely used as a pioneer plant in re-claiming degraded grassland on the Loess Plateau; under such conditions the plants are often cut when mature and dried at the homestead. The coarse stems are valued as fuel and the finer parts used as fodder.
Three of the commonly grown sweet clovers have similar growing conditions and cultural needs, namely M. alba, M. officinalis and M. suaveolens, and are dealt with together. M. indica, a subtropical annual grown in India, is treated separately.
Sweet clover; Bokhara sweet clover; Daghestan clover
Melilotus alba; M. officinalis; M. suaveolens
Sweet clover (sometimes called white sweet clover) (M. alba) is a white-flowered biennial, but annual forms exist. Bokhara sweet clover (M. officinalis) is yellow-flowered. They originate in Europe and northern Asia, but are widely introduced and naturalized. Daghestan clover (M. suaveolens) is a biennial with some annual cultivars.
The sweet clovers are suited to temperate climates and alkaline to neutral soils, but grow well at medium altitudes in the tropics. They can withstand very cold winters. M. alba and M. officinalis are widely sown in Canada and the USA. M. suaveolens is less widely used; in the USA it is grown in the north-central states. Sweet clovers can be grown in the high-altitude tropics; the annual Hubam cultivar of M. alba grew very well at Kitale, Kenya, as a cover crop and green manure. Sweet clover can re-grow from crowns with buds; to avoid it becoming a weed in the succeeding crop, it should only be ploughed in after the crown buds have developed into shoots.
Seed rate and establishment
Sweet clover is broadcast or close-drilled into a fine seed-bed at 10 - 15 kg/ha. Usually it nodulates freely, but lucerne inoculant should be used in new areas. The seed may benefit from scarification. Cvs Polara and Yukon are widely used in Canada, the latter for northern sites; cv Madrid is suited to warmer areas.
Spring-sown crops should have their first cut in late summer, giving adequate time for re-growth before winter. In the second year, two cuts are taken: the first should be cut high (25 cm), just before blooming, since old plants become woody and unpalatable.
Indian clover; senji
This yellow-flowered annual was previously an important rabi fodder crop in the irrigated tracts of northern India, but has been almost totally replaced by Egyptian clover (berseem), and, to a lesser degree, shaftal, both of which are higher yielding and produce better fodder. It does, however, tolerate salt, hot conditions and drought much better than either of its replacements and still finds a place on marginal land. It is smaller and more bitter than the annual forms of M. alba and its palatability is moderate. It is usually broadcast and gives two or three cuttings of green fodder. Nowadays its value lies in its ability to produce some feed on land too poor or degraded for the better clovers, and for using or reclaiming saline land. Only local landraces are available.
The genus Trifolium contains about 300 species; many are important in natural pasture and some twenty-five are cultivated. They are annual or perennial herbs and are among the most important fodders of temperate and Mediterranean climates. Some occur at high altitudes in the tropics, and most prefer rich soils.
Egyptian clover; berseem
Berseem is an erect, rather hairy, annual with a deep root system, and is trifoliate, with elongated, oblong leaflets. It is a very important cool-season fodder of the Mediterranean, western Asia, northern India and Pakistan. It is now grown in the USA and parts of Europe.
It is of ancient cultivation in Egypt, where it is a major winter crop, and from there was introduced to Sind in the early years of the twentieth century, where it proved so well-adapted to the conditions and farming systems of the irrigated tracts of the sub-continent that it spread rapidly throughout northern India (Roberts and Singh, 1951). It is now the major rabi season fodder, and cultivated on millions of hectares. This is probably the most rapid spread of a fodder species in recent times, and is all the more notable for being used mainly under small-scale farming conditions.
It is grown in the USA and, as a summer crop, in parts of southern Europe and at high altitudes in the Himalayan zone. Both single and multi-cut cultivars exist; the multi-cut Miscawi type is commonest. Egyptian clover has a high growing point and is not suited to grazing, but recovers well after mowing. Note that the name berseem is also used for other leguminous forages in Arabic speaking countries. Thus "berseem Hedjazi" is lucerne.
Figure 16. Training on farmers' fields - a good crop of berseem (Punjab, Pakistan)
It is a crop for areas with mild winters: while it withstands a light frost, growth is slowed or stopped by low temperatures. According to Fairbrother (1991), the usual limit in the USA is a winter temperature no colder than -6°C, apart from the cultivar Bigbee (Knight, 1985), which was selected from the Italian Sacramonte and will survive winters down to -15°C to -18°C. Bigbee is quick establishing and gives a good autumn cut if sown early. In southern Italy, it is grown as a rainfed winter crop. It will grow on a wide range of soils, preferring heavy loams, provided that they are not waterlogged. It is tolerant of relatively high salt concentrations.
Seed rate and establishment
In its main areas, berseem is sown in autumn, preferably early autumn, and establishes very rapidly; under irrigated conditions it gives four to seven or more cuts before flowering and dying off around May. Under irrigated conditions in Punjab, sowing is from late August to early November; the land is ploughed two or three times and planked to give a firm, level seedbed. Phosphatic fertilizer should be incorporated at 125 kg/ha P2O5. An irrigation is given immediately prior to seeding with 20-25 kg/ha of seed. The seed is soaked overnight and sown broadcast (often mixed with sand to aid even distribution) into shallow standing water. Chicory (Cichorium intybus) is a very common contaminant of berseem seed and may be removed by flotation at the time of seed soaking. If a nurse crop is used, such as oats, then that should be drilled in before irrigating and sowing the berseem. Only light seed rates of oats (20-30 kg/ha) should be used. Sometimes sarson (Brassica juncea) is mixed with berseem to give bulk in the early cut, but, unless very low seed rates are used, it depresses clover growth and reduces the overall yield since it does not persist into the later cuts. Sarson is a favourite vegetable in the berseem-growing areas. Turnips are also mixed with berseem. Italian ryegrass has frequently proved excellent in trials, but seed supply is a problem for small-scale farmers.
Much berseem is grown from local landraces of the Mescawi type, but many improved cultivars are available, although seed production often lags behind research. In Pakistan, cvs Agaithi and Pachaiti are recommended. In Egypt, the recommended seed rates are higher than those used in India and Pakistan.
It can be sown into standing rice at the last irrigation but, unless the rice is very thin, only limited success is likely. Sometimes, when speed is more important than good husbandry, berseem is sown into rice stubble without further land preparation; yields are, of course, lower, but when the last sowing date is approaching this assures some spring feed with minimal labour input. In more northerly areas or higher altitudes, cool-season crops must be sown early.
Where the crop is traditional, seed is usually available in the markets, often contaminated with chicory, shaftal and melilotus. Farmers often sell seed they do not need, or want, themselves. Berseem seed is easy to clean and good commercial samples are usually available; Egypt is the main source in international trade. Recently, the quality and availability of berseem seed in India and Pakistan has improved markedly.
Berseem is a free seeder where climatic conditions are right. Cultivation for seed production purposes is as for fodder, and one or two cuts are usually taken; late mowing, however, reduces seed yield. Good, clean seed must be used for seed fields and the usual precautions taken to ensure purity and trueness to type. The crop is harvested by hand, with care being taken to avoid shattering, and then dried and threshed. From 800 to 1200 kg/ha of seed can be obtained.
Maintenance and management
Ten to fifteen irrigations are required for fodder and about eighteen for seed production; very early sowings must be irrigated weekly at the initial stages, thereafter according to need. The first cut can be taken after fifty to sixty days if sown early in the season; the interval is greater in a late-sown crop. Cutting thereafter is at thirty- to forty-day intervals. The last cut will be in late April or early May.
The succulent stems are not easy to dry; hay is only made from the late spring growth when there is a peak of production, temperatures are high and the herbage is slightly drier. It is difficult to cure, and leaf drop is usually heavy once dried. Small-scale farmers often partially dry the crop in the field, then move it to house-roofs or other protected areas around the farmstead, and complete the drying there; the dropped leaves can then be swept up. In mechanized harvesting, a mower with a crimper speeds drying.
Crimson clover is an upright annual with striking, bright crimson conical flower heads. It is grown in southern Europe and the USA in the cool season for hay, often as a catch crop. It adapted to Mediterranean conditions and light soils, and is neither very cold tolerant nor drought resistant. Its seed has neither dormancy nor hard-seededness, and germinates immediately after ripening if in contact with moisture. It is easily made into hay in the hot season, when it is mown, but is hairy and not very palatable. Its cultivation is decreasing. It is drilled or broadcast, usually in autumn, at 15 - 20 kg/ha.
Red Clover is a fodder of ancient cultivation. It is an erect perennial, originating in the temperate and sub-arctic regions of Eurasia. It has probably been cultivated since the fourth century, but its wider use began in the seventeenth century in Spain, Holland and northern Italy. In cool, favourable conditions, the plant may persist up to seven years, but it should generally be regarded as a two-year crop. It became very important in temperate agriculture in Europe and North America as a soil-improver within arable rotations in the eighteenth and nineteenth centuries, and is still an important hay crop. In UK, it has regained some of its popularity and is now used as a dominant component in swards for silage making.
In warmer climates it behaves as an annual or biennial. Because of its upright growth, and shoots developing from its crown, it is better suited to mowing than grazing. There are two main types and an intermediate one, with a multitude of cultivar types. The Common group are early, rapid-growing, short-lived and less winter hardy types. The Late or Single-cut are slower growing, hardy and more persistent. Single-cut types are more productive than Common under the temperature conditions and long days of high latitudes.
It is cultivated in cool, humid, temperate regions, and withstands very cold winters. In North America, it competes with lucerne in the north, where the growing season is short. It has spread into subtropical regions at high altitude and under irrigation. A Chilean cultivar succeeded and seeded well at 1 800 m altitude in Kenya, grown as a one- or two-year crop.
Seed rate and establishment
Red clover is broadcast or drilled at shallow depth at 10 - 15 kg/ha into a firm seedbed. The seeds are small, so care must be taken in seed-bed preparation. In cool climates, it is generally spring sown under a cover-crop; in warmer climates, it is sown at the end of summer or the beginning of the wet season, usually in mixture with grasses, and perennial ryegrass is the commonest companion, although timothy and meadow fescue are also used, as a mixture of 4 - 5 kg/ha of grass seed and 10 - 15 kg/ha of clover seed. Spring sowing is preferred in areas of cold winters, since late sowing does not allow the seedlings to develop sufficiently to withstand the winter, and heavy losses can occur. Direct seeding is preferable to sowing under a cereal, since a laid crop will kill much of the clover. Seed is widely available and easily produced; the choice of cultivars, however, is often limited.
Red clover is an excellent and well-adapted hay crop, more easily handled when mixed with a little grass. Care must be taken to avoid leaf shattering, requiring careful turning and, in fast-drying conditions, by early putting into cocks or windrows.
Maintenance and management
Red clover is not suited to continuous defoliation, which rapidly leads to loss of stand. When not laid up for hay it should, therefore, be rotationally grazed or cut for silage.
White clover is a prostrate, creeping, white-flowered perennial with stems which root at the nodes. It is a pasture plant, mainly grown in association with grasses, but is used for hay. There are numerous cultivars, which can be divided into three main groups: the small-leafed wild types, which are more prostrate and suited to grazing, but low in yield and with very short stems; the medium-leafed or common group, which is intermediate; and the large-leafed Ladino types, which are tall, coarse and suited to haymaking.
Ladino clover is a general term used for the upright, large-leafed types of white clover, which are suitable for conservation. It is a spreading plant 40 - 50 cm tall, and almost a different crop from the small, grazing-type white clovers. It is as winter hardy as medium red clover, but less so than the small cultivars of T. repens. It is widely cultivated in North America, but rarely in pure stand except for seed production, since pure clover gives a dense swath which is difficult to aerate and dry, whilst mixture with a grass facilitates handling and drying. It associates well with tuft-forming grasses such as cocksfoot and timothy. USA cultivars include Regal, Sacramento and Lousiana. The Australian Haifa cultivar belongs to this group.
In northern Italy, it is usually cultivated as a three-year rotational crop (Piano and Pannicchiarico, 1995) and the landraces used do not persist well after the third year; mixture with timothy or cocksfoot is recommended. Espanso is an improved cultivar. Wild ecotypes closer in form to medium types are much more persistent than landraces.
White clover is a plant of humid temperate conditions, and which grows in all temperate climates where there is adequate moisture and soils are fertile. It also grows well at altitude in the tropics and subtropics if moisture and soil fertility are adequate. In East Africa, the Louisiana types are best adapted. It is not a plant for very poor soils, nor for dry areas, and stops growing when hot dry weather sets in, but can revive rapidly when conditions improve.
Seed rate and establishment
White clover is usually grown in association with a grass, mostly in multipurpose swards which will be grazed as well as mown. It is added to seed mixtures at about 2 kg/ha. When sowing along with relatively large-seeded grasses (some of the ryegrasses, for example) it may be best to drill the grass and broadcast the legume over it, covering the seed by roller. Ladino is the main type grown for hay in the USA - usually in mixture with cocksfoot. White clover is very sensitive to competition at the establishment stage, so grass seed rate, early management and grazing must be designed to assure the strong establishment and growth of the clover seedlings.
White clover is usually a component of mixtures, not a pure-stand crop, so mowing time will usually be dictated by the overall mixture. Ladino should be cut at full bloom. It forms a dense swath, which requires early but careful turning; to minimize leaf-loss, the crop should be windrowed as early as conditions permit.
Maintenance and management
Clover cannot be maintained in mixtures which are only mown - the grass will shade it out fairly quickly, especially where nitrogenous top-dressings are used. Clover-based swards must, therefore, be grazed hard early in the season and, where necessary, top-dressed with phosphate, and possibly potash, to encourage the legume. Nitrogenous fertilizer must be avoided. The fields should be laid up for hay in late spring and early summer; the aftermath should be grazed.
Shaftal; Persian clover
An annual from central Asia, which is grown as a winter crop in western Asia. The cultivated forms are robust clovers up to 40 cm tall. Small, weedy forms are common in pasture and on rough ground in the Mediterranean zone through to Punjab. It was common in Punjab, but has lost ground to Egyptian clover in frost-free areas since the latter's introduction to the subcontinent early in the twentieth century, and is a common contaminant of berseem seed there. It is a very important hay crop in Afghanistan and similar Asian areas of cold winters. It is a minor hay crop in Australia and USA.
Shaftal is a plant of the Mediterranean and subtropical zones. It prefers neutral to alkaline soils and will withstand a fair degree of alkalinity, much more so than will T. alexandrinum. It thrives on heavy, moist soils and tolerates waterlogging; it commonly colonizes the wet patches in fields of Egyptian clover. It withstands hard frost, but generally is very slow-growing at low temperatures. In the higher parts of the western Himalayas and in Afghanistan, however, it is grown both as an overwintering annual and as a summer catch-crop. The young shoots are used as a green table vegetable in Pakistan and Afghanistan. In upland Afghanistan, it is grown, autumn-sown, to above 2 500 m altitude, where winter temperatures fall below -12°C; under such conditions the plant is dormant, and snow-covered for months, but grows rapidly when temperatures rise in spring. In the larger part of its range it is cultivated as a winter annual, sown in autumn but producing little before spring.
Figure 17. Shaftal, with trusses drying on a bund (Herat Afghanistan)
Seed rate and establishment
Irrigated shaftal is established in the same way as berseem, but at a lower seed rate of 5 - 10 kg/ha. In its traditional areas, most is from locally-grown seed which has had little or no quality control, and in some places farmers use much higher seed rates. Seed quality should not be difficult to improve, as it is a free seeder. Landraces in Afghanistan, especially in Ghazni and Herat Provinces, where shaftal is a very important hay plant, are much superior to ordinary Pakistan material. Improved tall-growing cultivars are available internationally, such as cv Maral.
Sowing into another crop
Shaftal may be broadcast into standing rice at the time of the last irrigation. This can give a reasonable stand for minimal effort if the crop is a thin one with poor ground cover (as is often the case with basmati cultivars). In any well-grown crop, however, the clover seedlings are likely to be shaded out and the resulting crop is often late and poor. As a summer catch crop on high altitude sites in Afghanistan, it is sown in ripening wheat in late spring.
Shaftal makes good hay and is easy to cure, although the usual care must be taken to avoid leaf-loss. Traditional practice in parts of Afghanistan is to tie the crop into small trusses as soon as it is wilted, dry those first on the bunds, turning from time to time, and then in loose stacks before final storage. In this way, most of the leaves are retained within the trusses.
Several species of Vicia are grown as fodders, in areas of mild climate, often mixed with oats or other cereals. Most are rambling vines climbing by tendrils; the commonest are: common vetch (V. sativa), and woolypod, winter or hairy vetch (V. villosa subsp. varia (syn. dasycarpa)). Others of lesser importance include purple vetch (V. benghalensis (syn. atropurpurea)); bitter vetch (V. ervilia); Hungarian vetch (V. pannonica); and narrow-leaved or blackpod vetch (V. angustifolia).
Vetches are cool-climate crops that tolerate soil acidity and gravelly soils. They are grown as summer crops in temperate zones, and some are grown as winter crops in the Mediterranean and subtropics, especially V. benghalensis (syn. atropurpurea) and V. sativa.
In cool climates, vetches are usually sown mixed with cereals (oats or wheat), for hay or silage. Cultivars should be chosen so that the two crops mature at the same time. Seed rates vary greatly with species and cultivar, but 20 - 30 kg/ha of vetch is common, with twice as much of oats. Vetches seed heavily and on-farm harvest is simple, as it is a self-fertilized crop; seed crops may be grown with a cereal for support.
Harvesting as hay
Pure stands of vetch and mixtures should be mown when the lower vetch pods begin to fill. Again, it is important that the maturity of the vetch and its companion plant be synchronized. Vetch may tangle round the swathe board, so care must be taking in setting and using the mower.
North China milk vetch
A tall, hardy, robust long-lived perennial, which may attain 1.5 m in height, with a deep tap root. It occurs wild from central China to Mongolia. Cultivated types originate from central Chinese material. It has been widely used in pasture renovation, watershed management and fodder development in the Loess Plateau area. Its palatability is only moderate, and it is better accepted as silage or hay than in the fresh state. North China milk vetch withstands very cold winters, but requires a hot growing season. It prefers well-drained soils of high pH and survives on low rainfall, from 300 mm/yr, but uses a great deal of the available moisture. The common cultivars are very late flowering and their range in cold, northerly areas is limited by difficulties of seed production; they flower towards late summer, which is often too late for seed set if they are cut by frost. The crop may, of course, be grown for fodder in areas with too short a growing season for good seed-set. It grows wild as far north as the Mongolian Republic, so ecotypes adapted to shorter growing seasons must exist.
Seed rate and establishment
It is line sown at the onset of the rains at about 5 kg/ha of scarified seed, but may be broadcast. It is not usually harvested in the first year in semi-arid areas. Seed production is by cutting the whole plant once the seeds are fully formed, drying and threshing; seed growing areas must fit the flowering pattern of the cultivar.
The plants are usually cut once annually, at early flowering, then partially dried in the field and finally cured at the homestead. As with sweet clover in fuel-scarce areas, the stems may be used as fuel and the finer portions reserved for feed.
Maintenance and management
Mowing and perhaps weeding is all the crop usually receives once established, but top dressing with phosphatic fertilizer would improve its longevity and production.
Chinese milk vetch
A short-lived shrub which is widely grown in central and south China as a winter crop on rice fields which are not sufficiently well drained to allow the growing of wheat. Unlike many milk vetches, it is non-toxic and palatable, and well grazed by both large ruminants and swine.
It thrives in areas of mild winters, but will withstand light frost. It is tolerant of temporary waterlogging.
It is broadcast when the rice is harvested in autumn and grows luxuriantly in spring. The crop is cut in early spring, when other green feed is scarce. Immediately preceding ploughing, when the milk-vetch is usually in flower, it is grazed and some may be mown and dried. The remainder is ploughed under as green manure. It is a free seeder, and farmers save seed from reserved parts of green-manure fields.
A creeping, rhizomatous perennial, 30 - 50 cm tall with showy flowers, widely used in southern Europe as cover on road cuttings and other banks in need of protection. It is of European origin and is grown in the USA. Crown vetch's palatability is only moderate and it is very aggressive, so it tends to choke out associated plants in grazed mixtures. It is difficult to extirpate once established and will often re-establish after ploughing out.
Crown vetch is a plant of neutral to alkaline soils. It prefers warm summers but withstands cold winters. It is drought tolerant and will grow with under 500 mm annual rainfall. In northern Asia it has shown promise in experimental plantings on the Loess Plateau, and was the only really successful fodder seen in the Lhasa River Valley, at between 3 800 and 4 000 m altitude.
Seed must be hulled and scarified, and, in new areas, inoculated with a specific inoculant. Drill or broadcast at 5 - 10 kg/ha on a well-prepared seedbed in spring.
Harvesting as hay
The stems are coarse so conditioning would be useful. Under small-scale farming conditions, field wilting, followed by tripod or homestead drying, could be tried.
Sulla is a biennial, or short-lived perennial, herb with a deep rooting system. The cultivars grown for hay are erect, coarse, and grow to 1.5 m in height. The pods, which are lomented, almost thorny, and indehiscent, break into sections on harvest. It is important in southern Italy, Greece, southern Spain and North Africa. Prostrate ecotypes suited to grazing exist in the wild. Those cultivars of which seed is usually available are best suited to mowing, but can be grazed in winter and early spring (Kernick, 1978).
It is a plant of Mediterranean climates with mild winters, and will only tolerate light frost. It occurs naturally on deep, calcareous clays, but can be grown on a wide range of soils provided that they are alkaline, contain adequate lime and if the seeds are inoculated at the time of sowing. It is drought resistant and can be grown under rainfalls down to 500 mm/yr.
Seed rate and establishment
For hay it must be grown closely spaced, with an even stand, otherwise the stems will be too coarse for easy drying (the stems can be over 1 cm in diameter). A fine, compact seedbed is necessary and the sowing must be shallow. Hulled seed can be very shallowly drilled at 10 - 20 kg/ha; unhulled seed is usually broadcast at 30 - 50 kg of pods per hectare. Pods must be barely covered. Sowing is in autumn, but must be early enough to allow the plants to establish before temperatures become too low. In the Tunisian Tell, sulla should be sown before the end of October. When hot dry weather has prevailed at harvest (which is usual), there is a high proportion of hard seeds; scarification may be necessary. Hulled seed usually germinates evenly, whereas unhulled does not; the former is best for establishing hay fields; the latter is only suited to pasture improvement. Sulla for hay is sown in pure stand since its lush, tall growth from mid spring tends to choke out other forages in mixtures.
Harvesting as hay
Sulla grows slowly in winter but develops very rapidly in spring, with a peak of production from late March into May. It is usually dormant through the heat of summer. Several cuts may be taken in the second year. It may be grazed in winter and early spring when green feed is scarce, then set aside for hay. Martinello and Ciola (1996) state that, in Italy, sulla and sainfoin are usually grazed during October to April, and made into hay in May-June.
Maintenance and management
Sulla is a two-year crop and given little treatment other than grazing or mowing once established and any early weed control completed.
An erect, long-lived perennial growing to 50 - 75 cm, with a deep tap root and erect, hollow stems arising from basal buds on a branched crown. It originated in central and southern Europe and temperate Asia. Its indehiscent pods contain a single seed. It can be used for hay and withstands grazing better than does lucerne.
There are two types: common and giant. The latter gives more luxuriant growth but does not persist, and is used for two-year hay crops; common may persist for four to eight years. It does not cause bloat due to the presence of concentrated tannins in the leaves.
Sainfoin is not as high-yielding or as excellent a fodder as lucerne, but withstands drier conditions and poorer soil. Therefore, when used in the same area as lucerne, sainfoin is sown on sites where lucerne would not persist. It is adapted to dry, calcareous soils with a pH of 6 or higher under temperate conditions, and will withstand cold winters. It can grow with 300 mm annual precipitation and over, but must have good drainage. It is cultivated in central Europe, Turkey and the central Asian highlands, Kyrghyzstan, and Tadjikistan, and some Mediterranean countries, as well as North America. It has been tried on a field scale, successfully, in the Loess Plateau area of NW China. In Turkey and central Asia, it is traditional and popular.
Seed rate and establishment
Unhulled sainfoin contains a high proportion of hard seed. For hulled seed, rates of 20 - 30 kg/ha broadcast or close-drilled are used, with up to 100 kg/ha for unhulled seed. Eski is a cultivar developed from Turkish material; Melrose is Canadian; Zeus and Vala are Italian cultivars.
As for lucerne, but often only one cut is taken since the crop is on the poorer soils. The aftermath may be grazed lightly, but it is safer to rest the plants in late autumn and graze the aftermath once growth has ceased.
Ornithopus sativus and O. compressus
Serradella is the common name for two annual forage legumes from southwest Europe. O. sativus, pink serradella, is an erect, cultivated plant with no wild counterparts. O. compressus, yellow serradella, is widespread in natural grazing around the Mediterranean. They are semi-erect plants with pinnate leaves, which reach up to 50 cm in height. Their segmented seed pods break, on maturity, into segments, each containing a seed. Germination of unhulled seed is often low and erratic; they are hulled mechanically.
Both serradellas are grown as cool-season annuals in areas of mild winters and are well adapted to sandy soils. Outside its native area, serradella is grown in the winter rainfall zone of Cape Province and as a minor crop in Australia. It showed promise at high altitudes in Kenya in the 1950s, but was not adopted into farming systems.
Seed rate and establishment
Seed rates vary widely, from 5 to 15-20 kg/ha, as hard-seededness is common. Inoculation of seed on land where the crop has not previously been grown is recommended, but is unnecessary where serradella or lupins have been grown in the past. Lloveras and Iglesias (1998) state that pink serradella is grown on the Atlantic coast of Spain in double cropping systems with maize, or in multi-level cropping with grapes. The cv Carnota is mentioned and the seed rate used was 50 kg/ha of pure germinating seed.
It is mown in the usual way, with precautions against leaf-loss. In the Mediterranean basin, haymaking is usually from the peak of spring growth to early summer.
Some pulses are grown for hay. The haulms of many are good fodder, if they can be conserved. They are not, however, nearly as important fodder as the cereals.
Common groundnut; peanut
Groundnuts are rarely specifically grown as a forage but, properly handled in suitable climates, the haulms can be made into a high-quality fodder equivalent to good hay. Their harvesting is described in Chapter IX.
It is a warm-season crop that is killed by frost. Dry weather is essential for ripening and harvesting. Well-drained light, fertile soils are suitable; it will grow on heavier soils but harvesting on them is difficult. The crop cannot tolerate waterlogging. Commercial cultivation is usually in areas with about 1 000 mm annual rainfall, half of which should fall during growth.
It is usually grown as a row crop. Cultural practices which favour nut production also favour forage.
Guar or clusterbean is a strong-growing bushy annual, 1 - 3 m tall, with erect linear pods in clusters. It is traditionally grown in India and Pakistan as a vegetable, fodder and green manure crop. Its seeds are the source of a gum which has industrial and agro-industrial uses, and guar is now grown as an industrial crop in India and several countries with hot growing seasons, especially the USA.
It is a crop of the drier tropics and subtropics, and requires a hot growing season. It is very drought resistant and grows best on light soils. Some fodder cultivars have been developed in India.
In pure stand for fodder, the crop is broadcast at 30 kg/ha or drilled in close rows at a slightly lower seed rate. It takes about 15 weeks to come into pod. It is usually mixed with sorghum as a fodder on light soils under dry conditions. In India, it is often irrigated, and for fodder is often mixed with sorghum.
Guar and mixtures with sorghum, are made into hay, although care has to be taken in assuring that the stems dry through without incurring too much leaf loss, so windrowing or tripod drying is probably best.
Soybean or soya has been grown for hay in the USA and some subtropical regions, but needs a lot of labour and is out of fashion.
Soybean grows over a wide range of climatic conditions, provided that they have a hot growing season which is not too humid and that the soil is fertile and well drained.
Cultivar choice is very important, since it is a short-day plant and cultivars have a short range of photoperiod tolerance. Cultivars for hay are later maturing than those grown for hay. Sow thickly so that stems are not too coarse. It is usually row-cropped, seeded at 30 - 50 kg/ha, but can be mixed with Sudan grass for forage or hay.
Harvesting as hay
Mow when the beans are well developed and lower leaves yellowing - but earlier if weather so indicates. Cure in cocks if possible, or dry on tripods.
Field pea is an ancient and important crop, widely grown in temperate conditions as a vegetable and dried pulse. It is sometimes grown in mixture with oats or another small-grain cereal. The haulms of peas grown for fresh use or conservation are a valuable fodder if conserved at the time of harvest.
Peas need a cool and relatively humid growing season and fertile soils. They can be grown in the high-altitude tropics and as a winter crop in the subtropics, but their best growth is as a summer crop under temperate conditions.
A little is grown as fodder, usually mixed with oats. Pea haulms, available on a large scale from industrial crops for freezing and canning, as well as the fresh crop and pease straw are very useful by-products. Oat-pea mixtures were used to support peas grown for their grain but, with the development of modern pea cultivars that are much less affected by lodging, such mixtures have greatly decreased in importance. For hay, with or without a cereal, cut when the pods are filled, but well before ripening, as leaf-fall can occur at that stage.
Fenugreek is a highly aromatic annual used as a pot-herb, spice and fodder. It is widely grown in India and neighbouring countries as a flavouring and fodder, and in North Africa and western Asia as a fodder and spice.
It is grown as a cool-season crop in India and the Mediterranean region, both irrigated and as a rainfed crop. It will grow on a wide range of well-drained soils.
It is broadcast or drilled at 20 - 30 kg/ha in pure stand, or mixed with oats. Mixtures with small-grain cereals are best for haymaking. It should be mown when the pods are well formed. The hay is nutritious, but highly aromatic and may flavour milk.
Cowpea is a common bushy, trailing or climbing annual pulse of the tropics, subtropics and regions with hot summers. It originated in Africa, with a large number of types and cultivars. It is widely cultivated as a pulse and a green vegetable, and on a lesser scale as a fodder. It is grown for hay in South Africa and the USA.
It is a requires a hot growing season and good drainage, but tolerates poor, acid soils. On the equator, it can be cultivated up to about 1 500 m altitude. Cowpea can grow under low rainfall conditions and will give some crop on 300 mm.
Choice of cultivar is very important, as cowpeas are sensitive to photoperiod. They are usually row-cropped and may be mixed with maize, sorghum or similar for green forage.
Harvesting as hay
Cowpea should be cut at the green pod stage, but is not easy to dry; traditional methods involve tripods and a lot of labour. Cowpea can also be cured in long, narrow cocks after windrowing.