HAY CROPS - CULTIVATION METHODS

No crop is grown for hay alone; most of those described are used for sown pasture, or are field crops such as cereals or pulses. The cultural techniques and levels of input for other uses may differ from those for haymaking, and therefore that information should be sought elsewhere. Cultivation for hay is discussed, with the emphasis on techniques suited to small- and medium-scale farms. Hay crops are grown on arable land, where they must compete with other field crops on the grounds of profitability. As haymaking costs are proportional not only to the area worked, but also to the weight of the crop, intensive to semi-intensive methods aiming at high yields per unit area are therefore generally advocated.
Where land scarcity is the major limiting factor, increased yield per unit area may be the best way of improving fodder availability. This was demonstrated in Pakistan in an FAO-assisted project (Bhatti and Khan, 1996). Fodder crops cover some 19% of Pakistan's total cropped area, but there is still a chronic forage deficit; the area under fodder remained static during 1977 - 1994, at around 2 600 000 ha, while yields rose over 20%, from 17.4 t/ha to 21.4 t/ha, during the period. Well-grown crops of proven cultivars can produce 60 to 80 t/ha of green fodder (most fodder is irrigated), but there are still problems in assuring the supply of good seed and planting material at farm level.
In another study, in Punjab, Hanjra (1996) gives the results of 200 on-farm trials carried out over three years with the poorest and smallest dairy farmers in central Punjab. The "improved" methods mostly had three parameters which differed from the farmers' own methods: seed quality; sowing method (including land preparation); and date of sowing. The results are presented in Table 2. Yields are below the very high levels attained on research units and some large farms, but the effect of good seed, sown at the correct time, on a well prepared seed bed - all cheap inputs - is striking, with yields improved by 20 to 40%, except for sorghum, where no improved fodder cultivars are available.
Table 2. Yields of fodders with traditional and improved cultivation in the Punjab

Crop	Yield (t/ha; green)		Percentage increase
	Traditional	Improved method
Sorghum	18.5	20.0	7.5
Hybrid sorghum(1)	-	52.5	-
Maize	15.5	19.4	20.1
Berseem	26.3	38.5	30.9
Lucerne	25.0	34.4	27.3
Oats	15.0	24.6	39.0
Berseem+sarson+oats	32.0	41.3	22.5

Note: (1) Hybrid sorghum is multi-cut.

Land preparation

Clearing and levelling
Where fodder is cultivated for hay-making, the land must be prepared for mowing as well as put into a fit state for sowing and establishing the crop. Stones, stumps and termite mounds should be removed. Land with a long history of cultivation by the plough may require little or no treatment, but any field to be sown must be cleared of all obstructions to harvesting equipment. Under rainfed conditions, land levelling to facilitate mowing, as well as to make sowing of small seeds at even depth possible, is often necessary: even small humps and hollows make sowing at a uniform, shallow depth impossible and lead to gaps and uneven stands. For irrigated crops, of course, proper levelling is essential for effective water distribution. In-field irrigation structures should be designed to facilitate harvest, especially for perennial and multi-cut crops.
A firm, level seed bed is necessary for all fodders for hay, and for small-seeded pasture-type crops it must also be fine. Preparation methods vary with the type of farm and soil conditions. Whatever the means of primary and secondary cultivations, rolling in the final stages of seed-bed preparation, where possible, is advisable for all small-seeded crops. In tropical and semi-arid areas, work should follow the contour and, where necessary, precautions against washout should be taken. Most fodders have excellent erosion control qualities, once established, but the time of sowing and a short while thereafter are critical.
Fertilizing
Hay is a demanding crop and mineral deficiencies must be made good before sowing. It is a highly extractive crop, since all is removed from the field. Farmyard manure is rarely returned to fodder fields in developing countries, although it may be used on other parts of the farm, especially for horticultural crops. In large areas of the irrigated subtropics where fodder cultivation is important, most of the dung is used as fuel. In mechanized, intensive, large-scale dairying, however, the excreta is now handled in aqueous solution - slurry - which is widely used for top-dressing grass, adding fertility (from concentrates and other bought in feeds) and disposing of a difficult by-product in an ecologically benign way.
Soil fertility status should be determined before pasture installation. Local knowledge may allow a reasonable estimate to be made, but analysis may be necessary. While levels of laboratory accuracy may be very high, the value of analyses are only as good as sampling accuracy, so care should be taken, and advice sought if necessary on sampling methodology.
Phosphorus (symbol: P) is a major nutrient for all crops and its value is well established for fodder and grassland. Soils are usually deficient in available phosphorus unless they have been heavily fertilized in the past. It is essential for root and seedling establishment and should be present in the seedbed in adequate quantity and in a readily available form. It is also very necessary for legume persistence, and phosphatic top-dressings are frequently necessary to support persistence. It is progressively fixed by soil minerals after application, and on some tropical soils this process may be rapid and severe and almost permanent. However, there is thereafter a slow release, on which the sward relies for development. In grazed swards, much of the phosphorus is recycled through droppings. In hay crops, of course, this is not the case.
Potassium (symbol: K) is an essential nutrient, with a relatively high concentration in green leaves. Hays contain 2 - 3% in their DM, so it is a very potassium-extracting crop (a two-ton crop would remove the equivalent of 55 kg of potash fertilizer). It is required to complement nitrogen where high yields are the aim, as in hay production. Soil availability varies widely. Clovers are very sensitive to potassium deficiency.
Sulphur (symbol: S) is required in about the same quantity as phosphorus by plants, and legumes are often very responsive. However, it is much less used consciously as a fertilizer. Soil availability varies very widely. Some of the older fertilizers contained large amounts of sulphur; single superphosphate contains more sulphur than phosphorus; sulphate of ammonia supplies a lot of sulphur; basic slag, which was a major pasture fertilizer in industrial countries, contained appreciable amounts. More concentrated fertilizers with little sulphur are now common (partly to reduce transport and handling costs) and the steel-making process which produced slag is now little used, so the possibility of sulphur supply limiting production must be kept in mind.
Trace elements, or micronutrients, are limiting in some areas and application of tiny quantities in such cases can have spectacular effects. However, they should only be used, including cocktail mixtures, when a deficiency has been identified.
Nitrogen (symbol: N) is, of course, essential to all crop growth and its supply is one of the major limiting factors in forage production. An adequate nitrogen supply is essential, either as fertilizer or through biological fixation by legumes. Leguminous crops with effective nodulation will fix an appreciable amount of atmospheric nitrogen and add it to the overall farm nitrogen balance, but inputs of non-nitrogenous mineral fertilizer are needed to support this, as are increased management inputs in the case of mixed swards. For hay crops, heavy applications of N, including maintenance top-dressings between harvests, are limited by the resultant increasing density of sward, which hinders drying and can cause lodging and subsequent harvesting difficulties and losses. In small-scale farming situations, unbalanced use of fertilizer is a common fault: for unsophisticated users, the eye-catching responses to nitrogen top-dressing tend to eclipse the essential basal inputs of phosphorus and other necessary minerals. Nitrogenous fertilizer on legumes is wasteful and depresses biological nitrogen fixation.
Dressings for establishment will vary greatly according to local conditions, while maintenance fertilizer will depend on the management system. Levels should be decided according to local experience and research. A basal dressing of phosphatic (P) fertilizer is almost always necessary, and potash (K) is frequently needed; for non-legumes some nitrogen is necessary in the seed bed. Sometimes sulphur is deficient and leguminous crops, especially lucerne, can give large responses.
Calcium (symbol: Ca) is necessary for growth and legume nodulation. Under humid temperate conditions, heavy periodic liming, to raise the pH, is sometimes done. This is not suitable for tropical acid soils, but these may benefit from light dressings (600 kg/ha) of lime as a nutrient.
Micronutrient deficiencies should be dealt with where reported.
The forms of fertilizer used will often depend on local availability. For example, single superphosphate is recognized as being the best phosphate source for most fodders and pastures, but its phosphorus content is relatively low (17 to 18% P₂O_5, as opposed to 42% in triple superphosphate), so it is not interesting if long transport is involved.

Seed and planting material

The choice of crops for different situations and conditions is discussed in Chapter VIII. It is always advisable to use clean, healthy seed of the best adapted cultivars available. In developed countries, the pasture and fodder seed market poses few problems, although the availability of seed in bulk tends to be limited to a relatively narrow range of species and cultivars. In many developing countries, the fodder seed situation is difficult, especially for specialized fodder and pasture plants (as opposed to cereals or pulses used as fodders). Often, national priority has, in the past and probably correctly, been placed on producing seed of the major subsistence and cash crops, with fodder taking second place. The importance of livestock in most small-scale farming systems, and the present need for on-farm fodder production, however, mean that this imbalance should be rectified. The international seed market often provides only cultivars suited to a limited range of conditions (whatever the claims of the merchants) and is dominated by countries with a large internal fodder market, notably Australia, New Zealand and the USA.
Traditional fodder landraces, in developing countries, are often only available as farmers' seed from unselected crops, of very doubtful cleanness and purity. It has often been clearly demonstrated that fodder yields per unit area can be greatly increased, often more than doubled, by using good seed of locally proven cultivars and landraces. Many countries have the knowledge and basic seed within their research systems; the problem is how to develop a sustainable, local commercial production and distribution chain. In the sections on individual crops, cultivars will be mentioned; it must, however, be kept in mind that although a cultivar has performed well under similar agro-ecological conditions on another continent or in another country, it does not mean that it can be transferred to a new area with confidence. For example, local disease patterns differ, therefore fodder sorghums selected abroad and imported to Africa, where there is a strong disease challenge, often perform very poorly.

Irrigated hay

Fodder is a widespread irrigated crop in arid and semi-arid zones. Under small-scale farming conditions, usually within a mixed farming system, the greatest areas of cultivated fodder in the developing world are on irrigated lands in the Near East and the Indian subcontinent, often in wheat-rice farming systems and associated with milch buffaloes. Irrigation areas specifically for fodder are rare in the small-scale farming and pastoral sectors, but that in Xinjiang (Altai) (see Case Study 4 in Chapter XI) is a notable exception. In the large-scale sector, however, highly specialized fodder growing, again often associated with dairying, is common. Irrigation layouts should be so designed as to present the minimum hindrance to agricultural and haymaking equipment and should allow easy access for transport of the bulky crop. An adequate drainage system, to allow the fields to be dried off before mowing, is highly desirable.
Components of an irrigation system
Irrigation is not an end in itself, nor does the simple supply of water and seed to land assure a sustainable and economic increase in output. There is a complex interaction between the land and water base, agricultural practices and cropping choices, which interact on the system and affect its production, profitability and labour efficiency. The management and maintenance of irrigation require discipline; traditional systems depend on a stable community decision-making system, and all interventions require, well before proposal or execution, discussion at both household and community level. Irrigated farming communities are well aware of the systems' complexities. The main components are: (i) production activities (choice of crops, cropping and livestock system); (ii) on-farm water management (optimization of yield, and use of labour and inputs); (iii) the delivery system; (iv) the water supply system (relationship with local hydraulic system, reliability, quality, timing of supply); and (v) downstream implications (waterlogging, salinity, disposal of drainage). These are considered in more detail in the following sections.
Production activities
The choice of crops and cropping mixture is determined, within any climatic zone, by water availability, water quality, soils and the local market (both for sale of produce and supply of inputs). Where water is the limiting factor, the producers' aim is often to maximize return per unit of water.
On-farm water management
It is of the utmost importance that best use be made of the water delivered to the farm in order to optimize yield, not only of individual crops, but also of the farm crop mix, to optimize water-use efficiency, and to obviate land degradation due to waterlogging or salinization. The scheduling of water application to suit the plant-soil-water relationship of the site is essential. In addition to a good delivery system, in-field work is necessary. Proper land preparation, including levelling and grading, is essential to facilitate water application, economize on labour and power and to optimize input use (e.g., watering must be so designed that fertilizer remains within the root-run of the crops and is not lost in the drainage water.
These operations are essential to the correct running of an irrigated farm; their application requires knowledge of crop agronomy, land and water management
The delivery system
The system between the offtake and the farmers' fields requires both management and maintenance. Management must assure equity in water apportionment and assure the timing of each farmer's water delivery. It must also ensure that the canals and works are properly maintained; prior agreement on how this will be done is a prerequisite to any interventions. Maintenance, usually through communal participation, is arduous and can be time-consuming. It is often possible, through some redesigning and modification, to provide systems that are less liable to siltation and therefore require less maintenance.
The supply system
Two main aspects must be studied: the effect of an offtake on water availability for other areas downstream, and possible negative effects on the hydrological system. The final decision on most major offtakes, therefore, cannot be decided by discussion with the potential users alone, as all parties likely to be affected must be consulted. Modern, solid structures not only greatly reduce maintenance labour but allow a modification and prolongation of the cropping system by permitting irrigation over a much longer season.
Downstream implications
Irrigation systems can have undesirable effects on land downstream through salinization, waterlogging and damage caused as a result of drainage water disposal. Both the design of the delivery and the management of the water at farm level are involved. It is very important that these aspects be taken into account before interventions are undertaken. Since the user community may not be directly affected by the downstream damage, such effects must be judged in the light of their wider community and environmental effect.
Types of irrigation
Surface irrigation, in which the water is distributed through flooding by basin, border and furrow, is the ancient, traditional system, which still accounts for the vast majority of the world's irrigated farmland. It is likely that most irrigated small-scale farming fodder will be watered in this way. Surface water is distributed in several ways, and the main ones are discussed briefly below insofar as they affect fodder work.
The subject is very complicated. Standard texts should be consulted (such as Kay, 1986) for information on layout of irrigation units, their organization, and details of irrigation methodology. Crop water requirements and guidelines for their prediction are discussed in another FAO publication by Doorenbos (FAO, 1984). In considering irrigation of hay, however, care should be taken that the method chosen does not unduly hinder the use of whatever machinery is foreseen and that there will be adequate access at haymaking time for the type of transport to be used to remove the crop.
Basin irrigation
Basin irrigation is the oldest and simplest system: a field is divided into one or more basins; each basin is a piece of level land surrounded by a bund which retains water until it has soaked into the soil. It can be adapted to many crops and farming systems, but for fodder production it is very labour demanding and practically precludes any mechanization of harvesting, unless very large basins can be used. The in-field bunds have to be removed at each cutting, and in the case of multi-cut crops, reconstructed thereafter.
Border irrigation
Border irrigation (also known as border-check and border strips) resembles basin irrigation in that the fields are divided into units by bunds, but borders slope away from the farm channel in the direction of water flow. They are not level and the method of irrigating is different. The water is not retained on the field to soak in, but soaks in as it flows over the land, so it is important to use the correct flow for the correct duration to ensure that the correct amount of water infiltrates into the soil. This system is much better suited to haymaking than is basin irrigation. If cultivation and/or harvest is mechanized, border width should fit the equipment to be used.
Furrow irrigation
This is the most widely used system for row-crops: water does not flow over the entire soil area, but is confined to furrows between the crop rows, and infiltrates into the bottom and sides of the furrow. It is excellent for large fodder crops such as Napier grass, maize and sorghum, but it is not suited to hay corps. If cultivation and/or harvest is mechanized, row width should suit the equipment to be used.
Spate irrigation
Here the supply is dependent on torrents with only occasional flow, as after heavy rain or snow-melt. Traditional offtakes are very labour intensive, can often only be used when river levels are low, and may be completely destroyed by snow-melt floods in summer at a season when irrigated cropping can be very productive.
Qanat
This is a system (also called karez) of tapping underground springs by gently sloping tunnelling to transport it (underground) to cultivated land. It is widespread in parts of Iran and Afghanistan and is used as far east as the Turfan Depression in China.
Piped systems
Various systems of (usually underground) piping of water have been devised to reduce the enormous wastage of open-channel systems and to thus free more land for cultivation. The water is usually supplied to the field through up-pipes with valves (risers) in the case of underground pipes, or through gated pipes where they are on the surface. Accurate levelling and some in-field structures are still required for such systems. Alfalfa risers have their valves just below mean soil level so that once the crop is established the mower and other machinery can pass over them unobstructed.
Sprinkler irrigation
This requires a considerable investment in equipment, but has the advantage that great investment in land-levelling, drainage and other infrastructures is not needed; less land is occupied with irrigation structures; water is more efficiently used; and there is minimal danger of seepage losses and salinization through rising water tables. It does away with the need for in-field structures which hinder fodder harvesting.
Centre pivot
Centre pivot systems are large, computer controlled sprinkler systems which rotate around a central axis. They are widely used for fodder crops in semi-arid or desert areas, such as Saudi Arabia and California. They are primarily for large-scale commercial farms where fodder is a high-value crop, and are well suited to the task.
Cold season watering of hay-fields
Watering of natural hay fields before the thaw is traditional in parts of Russia and Mongolia. Water is diverted from springs and streams on to areas reserved for hay, with or without some in-field structures, and is stored by freezing on the surface. Traditional water-spreading methods practised in the Mongolian mountain-and-steppe zone involve sporadic diversion of streams to develop ice-sheets over hay land which will, thereafter, melt at the onset of the growing season.