This is the original source of hay, and is still common in parts of Asia and Europe. It is decreasing in large-scale commercial farming since better hay can usually be made more cheaply from sown crops, but it is still popular with subtropical and temperate small-scale farmers. Hay has yet to catch on with small-scale farmers in the tropics, probably because of the absence of a winter and the very poor quality of mature tropical grass.
"Natural" pasture takes many forms, all of which have in common only that the herbage has not been sown. It is usually on land unsuited to arable cropping for some reason: because of stoniness, seasonal waterlogging, slope or a short growing season, or due to pattern of rainfall distribution or temperature. Most is grazed, but some is used for hay, which is made on sites as different as meadows, almost sheer clearings on hillsides, subtropical forest land closed for regeneration, alpine grassland, steppes, or a host of other uncultivated lands. Natural hay is mainly from grasses and herbs, but in a few cases shrubs are mown and dried. Hayfields may be private or under common ownership, the latter often with customary rights. Several traditional systems of hay production are described in the case studies, including vast areas of forest land closed for regeneration or protection in India, where grazing is forbidden but grass-cutting allowed; the steep clearings of sub-Himalayan mountains; meadows in Turkey; the steppes of Mongolia (where cooperative stock-rearing has recently been replaced by private); the Sahel; and the Ethiopian highlands.
Various degrees of human interference or "improvement" have usually been applied to natural grassland, and more especially to the areas to be mown for hay. Fire is a potent grassland management tool, especially for the control of woody species and the removal of senescent herbage. Introduction of animals, domesticated or wild, has a great effect on vegetation. Manipulation of grazing pressure and control of grazing leads to changes in botanical composition without deliberate introduction of species. Bush-clearing, fencing, drainage, application of fertilizers and trace elements are more intensive interventions in modifying natural vegetation as pasture. Introduction of grasses and legumes, without much cultivation, is yet a further stage in modification. Many good natural grasslands have been replaced by arable while, in some countries, marginal agricultural land has been allowed to revert to "natural" grassland as the profitability of crop production declines. Self-sown, grazed, fallows are important in some systems.
The better pasture is usually reserved for hay, but many factors must be taken into account, in addition to good growth and suitable botanical composition of the pasture.
- Title to the use of hay land is essential; in some communities there are traditional hay lands and local customary practice for their use.
- Protection from stock during the growing season must be possible; in other than fenced areas, this would require the agreement of all users of the surrounding grazing lands.
- Topography and land surface must be suitable for the method of harvest and transport to be used.
- Accessibility for transport, as, although hay may be carted by many methods, including porterage in mountain areas, the fields must be easily reached by the mode of transport which is used locally.
- Areas infested with toxic plants that retain their toxicity once dried must be avoided. Often, such plants are not grazed by stock but will be eaten once cut and wilted or made into hay. Grasses with a high cyanoglucoside content are safe once dried, but plants such as goat's-rue (Galega officinalis) or ragwort (Senecio jacobaea) are a serious pasture weed in western Europe and parts of North America. Loco weed (Astragalus spp.) remains toxic when dried. For example, Faliu, Puyt and Jean-Blain (1985), discussing Galega officinalis poisoning from hay in southern France, stated that there is little danger from young plants, but if gathered when the plant is flowering or fruiting, the hay is dangerous if it contains over 10% Galega. Dickinson and King (1978) found appreciable quantities of alkaloid in air-dried ragwort.
Toxicity is not limited to the higher plants: mycotoxins occur in several forages. Some of the more important toxin-producing fungi in forages are Claviceps spp., which form sclerotia (ergot) in grass seed-heads, and Acremonium spp., which are endophytes (Towers and Seigel, 1993). Both produce ergot alkaloids. Claviceps spp. occur worldwide: C. purpurea infects hundreds of C3 grasses, and C. paspali occurs in nineteen Paspalum spp. Danger from ergot can be avoided by mowing before the seed-heads are formed. Acremonium endophytes are maternally inherited components of a grass-fungus symbiotic association; they are widely reported in Festuca arundinacea and Lolium perenne. Control is by replacing the crop with endophyte-free material.
These present problems of management, especially where strong, traditional systems are lacking or have broken down. It is essential that mowing and grazing rights on specific areas are defined by traditional or legal means. This is the case in most places where haymaking from natural pasture is traditional, but where the system has been interrupted (see the case study on Mongolia) difficulties can arise. If rights are not defined, there is no incentive to maintenance if anyone may mow.
Usually, in addition to defining mowing rights and dates of closure to livestock, the seasons when grazing are forbidden are also defined and fields may be open to communal grazing in the off season. If enclosure takes place, then real improvement of the herbage is possible. Similar situations existed in many parts of Europe before land titles were developed and farming modernized (see Fenton, 1980).
In the tropics, the quality of stand-over feed (and hay from mature material) is not at all the same as at higher latitudes or in semi-arid areas where stock can often overwinter on dried-off feed. 't Mannetje (1981) states that
"Tropical pastures do not meet the nutritional requirements of ruminants for maximum production. The main limitations are availability of green feed for at least half of the year in seasonally dry regions, and low nutritive value during most of the season of active growth."
Butterworth (1985) points out that the greatest limit on intake of green forage in the tropics is often the restricted amount on offer, including presence of material which is unpalatable because of senescence. The season of scarcity in the tropics is governed by rainfall, not temperature; the length of the dry season varies with latitude and site, from a few months to over half the year, but even when there is adequate moisture late in the season, especially in high-rainfall areas, the mature herbage may be almost worthless as animal feed and only selective grazing, and fire to "freshen" the grass, may assure survival of the stock. Hay made from natural grassland in the tropics is, unfortunately, much less likely to give satisfactory results than that from other zones; bush hay is usually made late in the rains because of the difficulty of drying at other times and is no better than straw or stover. This, along with a relatively low stock density in the past, may be why there is little if any tradition of haymaking in the humid and sub-humid tropics. Hay from sown crops can be made on mechanized farms under tropical conditions, but its quality will be governed by the genetic limits of tropical grasses, except at high altitudes, where exotics can be grown.
Discussing herbage quality from tropical pastures - at all stages, not just over-mature - Butterworth (1967; 1985) indicates that the crude protein content of 235 samples was 7.5% ±3.5%, with 235 under 7% (7% is the level for zero liveweight gain.). Crude protein content decreases with maturity as the cell contents are diluted by structural components. As the crude protein content decreases, so does its digestibility. Of 473 samples, 58% were below the needs for growth of beef cattle. The average total digestible nutrients (TDN) of 312 samples was 54.0 ±7.9%, with 43.5% below the 55% level recommended by the Agricultural Research Council (ARC) for grazing cattle; in tropical pastures, TDN is less likely to be limiting than is crude protein.
Figure 18. Precipitous hay land in Uttar Pradesh, India; the slopes in the middle distance are hand-mown for hay
Hay in the monsoon zone
Haymaking is traditional and widespread in the hills of northern India, Nepal and Pakistan. In the monsoonal lower hills, hay is made from communal grazing which is closed to livestock for several months, from before the monsoon and through it. Sometimes the stock are moved to high-altitude pastures. These hay lands belong to the community, but family rights to cutting are often recognized; the seasons of closure are agreed at village level. Hay is also made from areas of forest closed to grazing but where cutting and carrying off of grass is allowed by permit; the cutting season is determined by the forest authorities. During the monsoon, the weather makes haymaking difficult so the herbage is usually not mown until after the rains, by which time it is coarse, overripe and of low nutritive value. It is in these areas of chronic feed scarcity that hay is highly prized as a winter feed. The hay consists almost entirely of tropical grass genera, such as Heteropogon, Chrysopogon, Bothriochloa and Arundinella, which mature and lignify quickly. These "hayfields" are often steep to precipitous clearings, and all operations - mowing, turning, bundling and transport - can only be done by hand. The "management" of these hay fields is limited to decisions on closure periods (they are usually grazed after harvest and through the winter) and occasionally removal of invading shrubs, such as Dodonea viscosa. The hay produced in the hills is almost entirely for local use. In the drier parts of peninsular India, large amounts of hay are made from closed forests, but this is largely a commercial operation to supply the peri-urban dairies of the great cities, especially Bombay, so mechanized cutting and baling for transport are used.
Figure 19. Monthly precipitation and temperatures in Musoorie, India.
Figure 20. Natural herbage drying, spread out and then heaped ready for transport to the homestead (Mehterlam, Afghanistan)
Figure 21. Mowing over-ripe grass by sickle, after the main rains (Viet Nam)
Hay in the steppe
Mongolian winters are long and hard, and the growing season is less than 100 days for most of the country. The economy is almost entirely pastoral, so some hay is essential to help see weak stock through to spring, and also for the horses on which the herders depend for their work. For a long time, the livestock industry was organized into a small number of very large grazing cooperatives.
Crop and fodder production is limited by climate, although a little oat hay was made in favoured sites during the cooperative era. Most of the hay is made from natural pasture, with some 20 000 km2 being mown annually in the early 1990s by mechanized cooperative teams. The bulk of the hay land is in the north, and cooperatives bought mowing rights there. Hay was transported over vast distances at subsidized rates, especially for emergencies. Yields were stated to be a little over 1 t/ha of made hay. Management was mainly limited to land clearing and, sometimes, rotation of cutting date. Repeated mowing of the same land led to a gradual decrease in yields; fertilizer responses could be impressive if the rain fell at the right time, but was totally uneconomic. With the de-collectivization of the livestock industry into traditional units of small family groups, mechanized haymaking has disappeared, as has transport over large distances. Hay is now made locally, where herbage quality and availability allow, mainly by manual methods, but also with some horse-drawn equipment. Although herders have title to grazing land, title to hay land is still being organized, so management is chaotic. No improvement is likely until groups have long- or medium-term mowing rights.
Hay from tropical pasture
The causes of low animal productivity on tropical grasslands is mainly nutritional, because of poor seasonal distribution and low feeding quality of fresh herbage. Both quality and quantity are influenced by the stage and season of growth, climatic conditions and soils, as well as by the genotype of the forage itself. Mature tropical grass is highly lignified and its feeding quality may be even poorer than that of crop stovers; this may be one reason why hay-making is not traditional with most tropical pastoral peoples.
The case study on hay in the Sahel describes extension work on conservation of natural herbage in a climate with a very long dry season and a short and light rainy period. Maradi (Figure 22) is a typical station. Humidity is usually low and there is usually enough sunshine to allow mowing and drying in one day. Many tropical and subtropical sites (such as Musoorie; see Figure 19) do not have good drying conditions, so haymaking during the rainy season is not possible.
Figure 22. Monthly precipitation and temperature in Maradi, Niger
Meadow hay
In temperate and montane regions, natural hay is often made in low-lying, seasonally waterlogged, meadows. Although they produce a flush of herbage tall and dense enough to be mown (often containing rushes (Juncus spp.), broad-leaved plants and other bog vegetation), they are unsuitable for cropping. Until the development of sown fodder within a crop rotation, which was the key to intensification of both livestock and arable farming, this was the little hay which was made in western Europe. The quality of hay from such meadows is often mediocre. The studies from Altai (China), Mongolia and Turkey mention meadow hay. Smith and Crampton (1914), in their classic report on British grassland, when discussing meadows stated that the soils are generally porous loams with a high water table and usually subject to periodic flooding.
Meadows require greater summer warmth, and here are found in lowlands or in sheltered places such as riversides and estuaries. This would be an extensive group if soil and topographies were not so much used as arable land. Meadows occur at high elevations in Alpine conditions, with a permanent snow-line but warmer continental summers; under these conditions, the spring flushing of the slopes is widespread and growth rapid. The turbid water from melting glaciers is highly valued in the Swiss Alps and used to irrigate high pastures in many parts.
Trees and shrubs are important dry-season sources of feed, especially good quality forage, during the dry season in warm climates, and in winter in some cold climates. For the most part, they are wild or semi-wild, protected plants which are lopped, bowed or their pods are licked from the ground. Some trees are, however, used in the dried form; either their dry twigs and leaves are used (Alhagi in northern Afghanistan (Figure 23); Ziziphus spp. in the semi-arid subtropics; Leucaena and pigeonpea (Cajanus cajan)) or their pods are used. Although many trees are referred to as "multipurpose," it is the species which is multipurpose, not the individual trees, which must be managed for whatever main product is most desired, be it fodder, timber, fruit or firewood. The fruits of several leguminous trees are dried and used as feed, either from cultivated plantations or semi-domesticated stands. Though not exactly hay, they are dried plant products and should be borne in mind for areas where they are adapted. Pods provide a concentrate feed but may require treatment and grinding before use, since some have anti-nutritional factors, and also much of the feeding value is in the seed, which, unless treated, passes undigested through the digestive tract of the ruminant. The pods of the carob or locust (Ceratonia siliqua) of the Mediterranean region have been used since antiquity for both human and animal food, and are sold internationally; the tree fruits in southern Africa but has not developed there as a feed source (Topps and Oliver, 1993). The apple-ring acacia (Faidherbia (syn. Acacia) albida), which is widespread in the low-altitude semi-arid areas of Africa, produces large spiral pods which are prized as livestock feed. Some trees are planted, but the most are wild, but protected. The pods are harvested either for domestic use or sold as concentrate feed in local markets.
Figure 23. Hay from camelthorn (Alhagi sp.) drying (near Balkh, Afghanistan). A rare instance of hay being made from a shrub.
The seed pods of the algaroba - a tropical American leguminous tree - (Prosopis juliflora) are an excellent feed for ruminants and monogastric stock once properly processed. It is a very hardy and versatile tree adapted to areas of unreliable and low rainfall, and which can produce on saline soils and utilize low-quality irrigation water. It is a plant of warm climates and withstands only light frosts. Algaroba is a multipurpose species which produces timber, firewood and honey, as well as edible pods. For pod production, it must be cultivated expressly for that purpose, in spaced rows to allow full flower production. The foliage is unpalatable, so the under-storey of established stands can be grazed, but stock should be excluded during pod production.
Algaroba is widely used in its native region and is being developed industrially in northeastern Brazil, where small-scale farming production is combined with centralized processing. (Habit and Saavedra, 1988; Riveros, 1992). The tree has been widely introduced, naturalized and planted for firewood and soil conservation throughout the drier tropics and subtropics, but is rarely managed as a pod-producer; bush encroachment and small weedy trees, coppiced very young, are a common sight. Leaves which have dropped naturally because of senescence are very poor in nutrients.
Elsewhere, in some areas of serious feed scarcity, especially northern Pakistan and parts of the mountainous areas of Afghanistan, leaves from fruit and multipurpose trees, notably apricot and mulberry, are carefully collected and made into "hay" for winter use.
Land preparation
Where hay-making is traditional, the hay lands are often meadows, although there are also very steep mountain hay fields, which have usually been gradually cleared over a long time. It is essential that any land to be mown (by hand or mechanically) be relatively free from bushes, large weeds, stumps, projecting stones, termite mounds, pig-holes and other obstacles to mowing and raking. It is absolutely essential that this be taken into account when haymaking is proposed in a new area. In tropical areas, termite mounds are a big nuisance, and are soon rebuilt after levelling. For mowing by sickle, obviously, levelling is less important.
Drainage and irrigation
Hay meadows are often liable to localized waterlogging; drainage may be desirable to improve herbage growth, facilitate access at harvest time and reduce infestation by rushes and other undesirable plants.
Various types of irrigation and water-spreading are used in traditional systems, usually in spring. In parts of Russia and Mongolia, spring water is spread in the cold weather, when it forms ice-sheets; these provide supplementary moisture in the growing season. This technique is discussed in the Mongolian case-study.
Fertility maintenance
Haymaking is a very extractive form of land use, because all the minerals in the crop are exported, unlike grazing, where much of the fertility is recycled through animals' excretions. Continued cutting from the same area, therefore, means that, unless adequate maintenance fertilizer is applied, yields will drop rapidly over time and stabilize at a very low level.
Dung is rarely returned to hay-fields; that which is recovered is used on the crop land or as fuel. Sold hay is, of course, a severe loss of plant nutrients to the overall farm system. Herbage generally responds well to fertilizer, but the economics of its use on natural grass has to be studied before use; in semi-arid conditions with unreliable rainfall, fertilizer application is risky. Where rainfall is reliable, fertilizer can be applied sufficiently ahead of the haymaking season to assure an adequate crop. Nitrogenous fertilizer is the most commonly used, but - over time - balanced fertilizer application becomes necessary. Where legumes are present in quantity in the herbage, as in some Mediterranean pastures and high-altitude Asian meadows, phosphatic fertilizer will encourage their growth and thus improve hay quality. The effect of phosphorus is slower and less spectacular than that of nitrogen, so nitrogen is generally by far the most popular.
Seasonal closure and rotation
The pasture must be closed to grazing for sufficient time to allow growth of the hay crop; there are, of course, many variations on how this is done. Fields may be only mown; but often they are grazed at the beginning of the growing season when feed is scarce, and then closed until after the hay harvest. Usually a single cut is taken, but, occasionally, on very high-yielding meadows, two may be possible, but fertilizer might be required. Heavy grazing early in the season is generally detrimental to pasture growth, but often is resorted to when no other source of feed is available. Good growth is necessary on land reserved for haymaking and every effort should be made to protect hay fields at the start of the season, until their herbage is well enough developed to stand grazing. Fields which are mown year after year often show declining yields and degradation of the floristic composition of the herbage. It can be advantageous to rest fields from hay periodically, grazing them for a season or two.
Techniques and equipment used are described in Chapter II. The time of mowing is dictated by both the weather and herbage growth; the aim as always is to make hay when the herbage is at its best and the weather suitable for curing hay. These two conditions do not always coincide and while some manipulation of grazing to shift the date of herbage maturity may be possible, this is less than with sown fodder. Suitable weather is the over-riding consideration and this is taken to its most extreme in some parts of the Himalayas, where haymaking is delayed until the rains are over - and the herbage very mature indeed.
Late harvesting is frequently deplored by technicians in monsoonal and tropical situations, as noted in several of the case-studies. It is often not clear, however, how earlier harvesting and drying could be successfully attained. Much of the natural hay is made on poorly-levelled, often steep, land, using primitive manual tools and in monsoon climates, so mowing is pitifully slow and could not be mechanized; no artificial drying facilities are available and would not be economic. In such climates it is likely that hay will continue to be made at the start of the dry season. As soon as it is dry enough the crop (loose or baled) should be removed from the field and stored to allow re-growth of the aftermath and avoid damage by cocks or stacks of bales.
Figure 24. Carrying bundles of hay for further drying (Gujarat, India)
Photo: Ian Lane/C.S. Pandey
Yield estimation
Techniques for measurement of herbage yields are described in many textbooks[1]. An estimation of the available herbage, even if well done, is not, however, a useful guide to the amount of hay which will be produced. Much depends on the skill applied to haymaking - and the weather. Estimation by weighing or volume of the gross production of hay at time of storage, is much more likely to give useful information than sampling of green herbage, and at least provides a figure for the total available. Natural hayfields, especially in hilly conditions, are often irregular in shape and unsurveyed; estimates from sampling are meaningless if the area mown is not known precisely. Sampling of hay for quality analysis should be done on the made hay, not on the herbage from which hay is to be made! If only the standing herbage is sampled, losses in quality inherent in haymaking (leaf loss, leaching, transpiration) will not be accounted for.
Natural hay as a cash crop
Dried natural herbage is harvested in many areas and sold as hay or as fuel. Often in semi-arid areas, especially in Artemisia-dominated pasture, sub-shrubs are uprooted and sold as fuel in towns and villages. This destruction of rootstocks for fuel is a major cause of degradation of pastoral vegetation throughout much of the semi-arid regions.
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[1] For example: Brown, D.
1954. Methods of Surveying and Measuring Vegetation. CAB; Hodgson J., et
al., (eds) 1981. Sward Measurement Handbook. British Grassland Society;
Ivins J.D. (ed) 1959. The Measurement of Grassland Productivity. London:
Butterworths; t'Mannetje, L.H. (ed) 1978. Measurement of Grassland Vegetation
and Animal Production. CAB. |
