Chapter Eight

WATER AND NO WATER

THERE IS EVIDENCE that this small farm was originally carved out of the Long Forest, which once clothed much of South Shropshire, by men and women from the mixed Celtic Christian monastery at Much Wenlock, which, in the seventh century, was presided over by St Milburga, daughter of the king of the Saxon sub-kingdom of Magonsaeta. Those pioneers certainly had an eye for water. Just below the circular earthwork which, I am convinced, was the site of their monastery, rises a spring, whose delicious water we still customarily enjoy, though it sometimes runs dry in times of drought. In the centre of the five-acre field, once called ‘Middle Stocking’, another spring rises from a perfect example of a ‘knickpoint’, the geological term for the lowest point of a hillside contour, where the slope flattens out and where the groundwaters tend to meet to form a spring.

Fig. 18 Early Celtic Christian settlement

The keen eyes of P. A. Yeomans, the Australian mining engineer, farmer and conservationist, trained in landscape assessment, intuitively recognised in the ‘knickpoint’ the clue to his Keyline System of land reclamation. He renamed the ‘knickpoint’ the ‘keypoint’ and called the contour which passes through it the ‘keyline’. The essence of his system is contourploughing parallel to the keyline with a non-inverting chisel-plough invented by himself. This has the effect of creating thousands of small channels, which cause the groundwater to spread across the slope instead of converging on the ‘knickpoint’. The circulation of mineral-carrying water so brought about has the effect of releasing stores of fertility ‘locked up’ by soil compaction. The result, as Yeomans triumphantly proved on his farm at Yobarnie, New South Wales, can lead to the regeneration of land condemned by agricultural experts as ‘irredeemable’, after it had been baked as hard as concrete by a forest fire.

The Keyline System might have great significance for rainforest areas whose thin ‘lateritic’ soils have also been concretised by the twin forces of tropical sun and tropical rainfall, after the forest had been burnt to death to provide brief pastures for ‘hamburger ranches’. In fact, Keyline would seem to provide a good chance of restoring those degraded soils and making them once more productive.

Yeomans developed his system into a comprehensive method of landscape architecture, applicable to any reasonably large undulating area. One refinement was the building of a series of small reservoirs along the contours, which could be temporarily dammed for sheet-irrigation. Another was the planting of shelter-belts of trees to distinguish the Keylines.

The idea of landscape design seems to be deeply rooted in the Australian consciousness, as the people’s ancestors of not-so-long-ago were involved in opening up virgin territory. Bill Mollison, also an Australian, makes landscape design the centrepiece of his system of Permaculture, which he first conceived in the early 1970s at the same time as I was, quite independently, working out my own system of Organic Perennial Subsistence Agriculture or Ecocultivation. In Permaculture One, written by Mollison and David Holmgren, the authors say:

Permaculture is a word we have coined for an integrated, evolving system of perennial or self-perpetuating plant and animal species useful to man. It is, in essence, a complete agricultural ecosystem… Perhaps we seek the Garden of Eden and why not? We believe that a low-energy, high yielding agriculture is a possible aim for the whole world.

I couldn’t agree more.

In his book Permaculture Two, Mollison speaks with authority and passion about a problem which is dominating ever-growing sectors of the earth’s surface: how to rehabilitate arid lands. Referring to Australia’s vast empty spaces, Mollison affirms:

I must state that, in my opinion, based on real examples sighted, the ‘dead centre’ is a myth. Not only will many important vegetables and tree crops grow in deserts, but the native vegetation, where not overburnt or overgrazed, is, in itself, a great resource. Water lies close underground in many places… Growth in desert soil is phenomenal if water is available.

Listing a number of systems for trapping, conserving and utilising every available drop of water, he shows that a large number of trees and other perennial plants can be induced to grow in areas regarded as barren wastes. These include figs, olives and grapes, the three staples of arid and eroded areas in the ancient Mediterranean, as well as mulberries, date palms, oranges, lemons, carobs, mangoes, cashew nuts, jujubes and pomegranates.

In his great book Permaculture: A Designer’s Manual Mollison describes in exhaustive detail numerous techniques for the reclamation of deserts and other arid lands – techniques which may well have to be applied in Britain and other European countries, as well as much of the rest of the world, if drastic steps are not taken to reverse the Greenhouse Effect.

Mollison paints a fascinating picture of the desert garden, as found in Central Australia, from which we in Britain may have much to learn if summer droughts continue. The garden is integrated with the house, for which it provides shade, shelter and climate amelioration. The roof may be covered with soil and planted with ice-plants, succulents and hardy desert species. This roof-garden cools the house in summer, when watered, and insulates it from winter cold. Trellised vines on the walls have a similar effect. Hedges of tamarisk, white cedar, paulownia or bamboo screen the house from cold winds. Arbours are formed adjacent to the house, in which strawberries, blackcurrants, gooseberries and herbs are grown, deeply mulched to retain moisture. Lean-to greenhouses provide winter greens, peppers and tomatoes, as well as spices and other flavouring plants such as ginger, turmeric and vanilla. All waste water from the house is fully utilised. Sewage and ‘grey’ water from baths and sinks is conveyed to perforated pipes beneath the garden. Sludge from septic tanks is conveyed to planting holes, covered with soil and then planted with dates, figs, citrus trees or mulberries. If the house is situated on a frost-free hillside, tropical plants such as guavas, papayas and mangoes, sheltered by trees such acacias and paulownias, may grow successfully, being irrigated by wind-pump. If possible, the house is built near a water run-off area, such as a rock, and care is taken to see that all the water is absorbed into sand-plots or ‘swales’ – contour ditches designed to trap water which release it gradually into the soil.

The staple plants of the desert garden are drought-tolerant species, able to survive on minimal watering, such as dates, olives, avocados, apricots, bananas, sweet potatoes, cucumbers and melons. However, most tropical and temperate vegetables can be grown in small beds, soaked every 3-10 days and shaded by slats, vines or leguminous trees. The legumes inject nitrogen into the soil. Other companion plants are used, including marigolds, gladioli and wallflowers, so that the desert garden can be gay with colour.

Many irrigation devices have been used in the past – and are still used – to ensure that gardens and orchards in arid lands are places of beauty and fecundity. A notable example is provided by the elaborate waterworks created by the Moorish cultivators in Southern Spain, which included dams, aqueducts, reservoirs, sluices, tunnels and siphons.

In the Far East many upland areas have been terraced with incredible skill, to ensure that every available drop of water is utilised for growing crops. Alfred Russel Wallace, the famous Victorian biologist, who conceived the theory of natural selection independently of but contemporaneously with Charles Darwin, recounts in his book The Malay Archipelago his astonishment at the system of cultivation which he discovered on the Indonesian island of Lombok, from which at that time almost all Europeans were excluded:

I rode through this strange garden utterly amazed, and hardly able to realize the fact that in this remote and little-known island… many hundreds of square miles of irregularly undulating country had been so skilfully terraced and levelled, and so permeated by artificial channels, that every portion of it can be irrigated and dried at pleasure… Here were luxuriant patches of tobacco; there cucumbers, sweet potatoes, yams, beans or Indian corn… The banks which bordered every terrace rose regularly in horizontal lines above each other, sometimes rounding an abrupt knoll and looking like a fortification, or sweeping round some deep hollow and forming on a gigantic scale the seats of an amphitheatre. Every brook and rivulet had been diverted from its bed, and instead of flowing along the lowest ground were to be found crossing our road half-way up our ascent, yet bordered by ancient trees and moss-grown stones so as to have all the appearance of a natural channel, and bearing testimony to the remote period at which the work has been done. As we advanced further into the country, the scene was diversified by abrupt rocky hills, by steep ravines, and by clumps of bamboos and palm trees near houses and villages; while in the distance the range of mountains of which Lombok peak, eight thousand feet high, is the culminating point, formed a fit background to a view scarcely to be surpassed in human interest or picturesque beauty.

Fig. 19 Water-wheel for irrigating bog-garden

A system of water control that was developed over 2,000 years ago in one of the harshest arid areas in the world, that of the Negev Desert, has been successfully revived by an Israeli professor, Michael Evenari. The system was originated about 200 BC by the Nabateans, builders of the famous rock-hewn city of Petra. It comprises an ingenious complex of run-off channels, small dams, trenches, terraces and cisterns, designed to gather up the meagre rainfall – three to four inches a year – and concentrate it in a single growing area. Evenari refined the system to the extent that he created microcatchments, each designed to irrigate a single tree or bush: olive, pomegranate, peach, apricot, fig, almond, grapevine or saltbush (used for fodder). Yields from this modern version of an ancient system were extraordinarily high, and so impressed a German relief group that they translated the system to a heavily eroded area of Bolivia. There, in a strange ‘lunar’ landscape of gullies and dome-shaped mounds, they recreated Evenari’s microcatchments into forms that were nicknamed by the local inhabitants medias lunas – ‘half-moons’. Each of these comprises a small rainfall collection area, with an earth wall on the downhill side to prevent erosion; in each two saplings are planted: leguminous trees bearing high-protein beans, intended to provide food, fodder and firewood, while improving the fertility of the soil by injecting nitrogen. The retention of moisture in the soil has had the effect of attracting the colonisation of wild plants, and it is hoped that a train of ecological succession has been set in motion, the culmination of which will be a dense climax forest, like that with which the area was originally clothed.

More and more it is being recognised that the tree provides the masterkey to the reclamation, fertilisation and regeneration of arid lands. Where large numbers of trees are planted there is no need for elaborate irrigation schemes. Such schemes, with their associated big dams, often involving the drowning of hundreds of square-miles of fertile land, may lead to ecological disaster. The irrigated soils tend to become heavily salinated and therefore incapable of growing crops, while the reservoirs become silted up and lose their utility. Trees, on the other hand, with their complex root-systems, create their own irrigation channels in the soil, through which pass pure life-giving streams of water, laden with subsoil minerals, which nourish other crops.

No country in the world understands the value of trees as does China, which, in recent decades, has planted countless millions for the reclamation of deserts, for shade, shelter and windbreaks, and for the control of water, to halt the cycle of floods and droughts which has been one of the banes of China’s history.

Trees can be used not only for the restoration of arid lands but also for the prevention of flooding. One of the main causes of floods in many countries, not least Britain, is the felling of forests and the draining of marshes in upland catchment areas where most rivers and streams have their sources. This means that there is little absorption of precipitation in those areas. Storm water races down the denuded slopes, and rivers and streams become suddenly swollen and burst their banks.

Forests not only make rain by transpiring groundwater into the atmosphere, but they also absorb rain through their roots and then release it gradually into the groundwater system, so that ‘flash floods’ are rare in a forested area. The simplest and most effective way to stop flooding, therefore, is to restore tree-cover to upland catchments. Marshes in the same areas could, I suggest, be transformed into economically viable wetland permacultures.

A large and very remarkable ‘forest garden’ called Sol y Sombra (Sun and Shade), including some 150,000 economic trees and shrubs, has been created by Beth and Charles Miller high up in the hills near Santa Fé, New Mexico. In this arid area rainwater is harvested by more than 100 ‘swales‘. Sewage and ‘grey’ water is treated by a reedbed system, comprising four-gravel beds and two ponds, planted with reeds, rushes and bog flowers.

In recent years a number of systems for treating waste water by natural, biological techniques have been developed in many parts of the world. These systems are highly compatible with agroforestry principles:

1.  They make use of plants and bacteria to purify and detoxify potentially harmful material, transmuting it into useful resources, including energy and fertiliser.

2.  They help to conserve the environment, creating beauty and attracting wild-life.

3.  They are largely self-sustaining, requiring minimal maintenance.

A feature incorporated into many of these systems is the ‘flowform‘, a series of concrete basins carefully sculpted to impart rhythmic, pulsing movements to the water, which, it is claimed, help to oxygenate it and enhance its ability to support the purifying organisms.

The reeds and rushes, which often play a key role in water treatment systems, have many traditional uses. Richard Mabey in his Plants with a Purpose (Collins, London, 1977) writes: ‘It is the common characteristics of the stems of reeds, rushes and sedges that make them so useful and adaptable. They are long and straight, always lightweight and often hollow. The grouping of tough fibres round the outside of the stems makes them pliant, durable and easy to work. They are ideal, therefore, for weaving or bunching into hardwearing articles like baskets or mats.’ ‘In Nevada,’ Mabey declares, ‘the Paiute Indians weave rush cradleboards for their babies and, with a real understanding of the natural waterproofing of a plant that spends its life up to its knees in the wet, makeshift boats.‘

The reedmace, Typha latifolia, often erroneously called ‘bulrush’, is a plant with a multitude of uses. The familiar long brown spiky flowers, which give it its American name of ‘cattail’, can be cooked and eaten. The seeds are also edible and yield an edible oil. The pollen is a first-class source of protein, and the young shoots can be eaten like asparagus. The core of the rhizome contains more carbohydrate than potatoes and as much protein as maize or rice. Of all wild plants, the reedmace has been described as the most useful emergency food source. But the leaves and stems also yield fibres that are used for weaving and have potential value for paper-making. Mexican studies have shown that woven reedmace leaves, when coated with plastic resins, are as strong as fibreglass.

At this time when the threat of the Greenhouse Effect looms over the lives of all of us, a special study should be made of temperate plants which require a minimum of watering, comparable to the studies made of drought-resistant plants in the tropics. The common characteristics of such plants seem to include:

1.  Small or waxy leaves which reduce evaporation;

2.  Hairy leaves that retain moist air, keeping them cool;

3.  Hollow stems, used for storing water (onions and thistles);

4.  Ability to survive in shallow grassland or on rocky slopes (thyme, marjoram and yarrow).

5.  Deep roots, which extract water from the subsoil.

Among tactics which I employed to combat the severe drought in England in 1995 were heavy mulching to preserve the moisture in the soil and drastic pruning and weeding to minimise stress in the more valuable plants.