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The Sahara: an ever-present challenge


RICHARD ST. BARGE BAKER is the founder of the Men of the Trees Society. In retirement, he now dives in New Zealand but he is as interested and active as ever in Saharan problems.

IT WAS SOON AFTER MY APPOINTMENT as an assistant conservator of forests in east Africa in 1920 that I became aware of the importance of attempting to arrest the advance of the Sahara in equatorial Africa.

Reports had arrived of what was happening to the north where the tribes had been caught in a wedge of vanishing forest with hundreds of miles of desert in front of them and desert closing in behind them. Chiefs had forbidden marriage and women refused to bear children for they were driven before the oncoming desert and could already see their end in sight.

This made a profound impression and I was determined to do what I could in my fairly responsible position in charge of thousands of square miles of Kenya, including near desert stretching north to Turkana and beyond, when it seemed that the steady advance of the Sahara was inevitable unless it were contained by a series of protective forest belts.

The planting grant was negligible and I was driven to the conclusion that it was essential to obtain the willing cooperation of the people to stem the tide of destruction.

Dance of the trees

It had been brought to my notice that, whenever any constructive effort was to be made, it started with a dance; for instance, there was a dance when the beans were planted and another when the corn was reaped. So I invited the captains of the dances to my forest station at Muguga to discuss the situation and arrange for a nationwide inauguration of a new dance -the dance of the trees-for tree planting.

It entailed much preparation, with the sending of runners to distant parts of the country. Eventually the great day of the first dance of the trees arrived and 3 000 morans or younger warriors turned up at my forest station, decked out in their war paint and carrying spears and shields as if prepared for battle, but on the point of each spear was a ball of ostrich feathers-a sign that they came in peace. At a given signal the warriors marched past the bungalow, clan by clan; on they came in a constant stream and fell into their ranks before a solitary, sacred mugumu tree-a ficus closely related to the banyan of India.

I should mention that, whenever the Kikuyu felled a forest to make a farm, they would leave a single mugumu tree to collect the spirits of the other trees so that these would not, as they put it, wander about and be uneasy. This thoughtful consideration for the spirits of the trees they were felling convinced me that at heart they were tree lovers and it would not be too difficult to teach them something of the biological contribution that trees make to life and their essential place in an agricultural community. At first when I had talked to them about the importance of tree planting, they said: that is shauri ya mungu-God's business. Trees just grow by themselves. It had not dawned upon them that, if they felled all the mother seed trees, there would be little chance of regenerating a new forest. Their nomadic methods of farming meant their having to go farther and farther afield to get sticks to cook their food. Whereas before a journey of an hour or two sufficed, now they might have to go two or even three days to meet their needs. It was their women who went to the forest to collect the firewood and it was the women who planted and cultivated the garden crops, such as beans, peas, yams, okra and sweet potatoes. And so to the first dance of the trees came women in their thousands with children and old folk.

All assembled on the clearing behind the forest station near the sacred mugumu tree. Never before in the history of their country had such a gathering taken place. It was a wonderful sight. From the platform that had been specially built for the occasion, I spoke through Chief Josiah Njonjo who, with his natural oratory and vivid imagination, amplified the appeal that I was so earnestly attempting to make to these nomadic cultivators who for generations had been felling the high forest to make their farms. That day, it was 22 July 1922, I called for volunteer planters of trees.

The volunteers were soon nicknamed: Watu Wa Miti -men of the trees. They had come forward and, like scouts, promised to do one good deed each day and, in addition, plant ten trees, seedlings or seeds each year and protect trees everywhere. The idea caught on, for in future no one was allowed to be present at the dance of the trees who had not fulfilled his planting obligation. Each branch of the Watu Wa Miti was under the supervision of a leader known as a forest guide. The trees were planted between their corn and sweet potatoes and left as a potential forest on the old farm when they moved on to cultivate a fresh clearing. In this way we were able to reestablish and improve on the original tree cover with such valuable species as mutarakwa (Juniperus procera), the Kenya pencil cedar and mutamaiyu, the Kenya olive, and other valuable timber trees. Incidentally it was of ecological interest to find that pigeons fed on the juniper berries and that the seeds that had passed through the guts of the pigeons germinated. The viability of the seeds was short and it was necessary for the outer covering or pericarp to be disintegrated before the seed could germinate. It was through studying nature's method that I was led to soak the seed in hot water with a small amount of sulphuric acid to approximate the effects of the gastric juices of the pigeon. When the juniper fruit was sown untreated, there was less than 5 percent germination. [Following nature, 95 percent germination was secured and soon there were tens of thousands of seedlings in the nurseries ready for transplanting. And this was at Muguga, meaning a treeless place.

FIGURE 2. - There were extensive forests of great trees of which ] and roots are found.

Muguga was one of the most beautifully situated forest stations in the world for soon after dawn I could usually see the 5 200 metre snowclad mountain of Kirinyaga, place of whiteness, for which Kenya is named, and to the south from the veranda was displayed the 5 800 metre flat-topped mountain of Kilimanjaro which looked like a giant breakfast table with real snow as a tablecloth.

To Muguga came members of the Watu Wa Miti whenever they could not think of a better good deed, to plant out small mutarakwa trees. This was a labour of love and undertaken as any other game or recreation, and in that first nursery they raised over 80 000 young trees.

I have mentioned these details because I believe so strongly in the voluntary cooperation of a people in contrast to any system of compulsion, especially with regard to large-scale afforestation under difficult climatic conditions when :much loving care is needed.

In appreciation of the :many years of devoted service of Chief Josiah Njonjo I invited him to come to London in ]953 as my guest for the Coronation of Queen Elizabeth II. When his plane had touched down he was interviewed by the British Broadcasting Corporation for their daily programme, In Town Tonight:

" You are a Chief from Africa? " inquired the interviewer. " Yes " said Josiah, " I hold King George's Gold Medal for long service and now I have come to see his daughter crowned." " And what are the duties of a Chief? " asked the man from the BBC. " The Chief is the voice of the government to the people and the voice of the people to the government." " Tell us about this Mau Mau business," said the interviewer. " That is a long story," said the Chief, " and I am no politician but I can tell you this. In my part of Kenya we have had no trouble at all." " How do you account for that, Chief? " inquired the interviewer. " Because over 30 years ago a forester taught us how to plant and protect our native trees. We have kept the promise made to him and so we have plenty of timber, plenty of fuel, plenty of clear water and we have plenty of food, so no trouble."

Surveys to restore nature

In 1953 there were two great adventures in progress one was known as the conquest of nature- a group of brave and hardy men suffered great hardships anal risked their dives to stand on the summit of Mount Everest. The ascent was visualized as a fight between the brains, muscles and powers of endurance of man, and what was called the blind forces of nature. So, if man ever stood on the summit, he would claim to have conquered nature; but the life of the everyday world would flow on, entirely unaffected by this: heroic expedition.

In the other adventure, a party of four men went out to the Sahara to fight the evil which men had done to the soil of Africa and find ways to restore to nature the deserts created by man's ignorance. They, like the Mount Everest party, suffered great hardships and risked their lives. One died. The exploration survey was successful, but the full effect of its work, which will continue, may not show for years and will still go on for generations. Unlike the mountain adventure to conquer nature, the desert adventure to restore nature was carried out with the object of giving back to the human race thousands of square kilometres of food-bearing lands.

Ten thousand years ago the Sahara was apparently teeming with human, animal and plant life. The art galleries of wall painting at Tassili-n-Ajjer and elsewhere could indicate the drying up of the rivers and the shrinkage of lakes, for the earliest drawings depict elephants and hippopotami. Geologists and anthropologists have given them a tentative date of 5000 BC and it is known as the Period of the Hunters. Next comes the Period of the Herdsmen around 3500 BC followed by a well-defined stage of the horse, the dog and the wheel, with the four horse chariot about 1000 years BC.

It is of interest to find remains of trunks of trees and root systems. Sometimes curious mounds enclose all that remains of what was once a tree stump. But what concerns us most as foresters and land reclamationists is the speed at which the Sahara is advancing today. There are indications that it is advancing faster thin: an ever before, and not only along the southern perimeter but presenting an equal threat in the north after long droughts.

The findings of the 1952-53 Sahara expedition were reported in the book Sahara challenge, the last chapter of which presented an overall plan for Sahara reclamation. Another round of the Sahara expedition was organized in 1964 after a conference at Rabat to which all heads of state had been invited by the Sahara Reclamation Programme of the Men of the Trees. This has been briefly recorded in Sahara conquest, which invites cooperation on an international scale not only to combat erosion and contain the Sahara but to help the political climate of the nations.

Driving along the foothills of the Atlas mountains while carrying out the ecological survey, with over 3 000 kilometres of desert stretching away to the south -through which we passed on our way to Kano - we thought of the Alb or Albian Nappe, that vast subterranean source of water lying beneath our track. Its existence had been anticipated by explorers and geologists but it is only in more recent years, by means of magnetometer surveys, drilling for pilot development wells and periodic measurements of discharges, that its extent and formation have been identified. Geologists explain that these are deposits left by streams and rivers perhaps 50 million years ago. In the early chalk period, which preceded this continental epoch, these deposits were sealed in by marl and clay left by the sea. This is the geological explanation for the subterranean Sahara, lake, Nappe Albienne, which stretches l 000 kilometres southward from the southern foothills of the Atlas mountains, is bounded on the west by the Saouva valley and on the east by Tunisia and the Libyan Fezzan.

FIGURE 3. - When tree cover is removed, the desert takes over. Tassili Ajjer.

FIGURE 4. - Dune stabilization and reafforestation under-taken by the Libyan authorities with the help of FAO foresters.

FIGURE 5. - A row of olive trees at Sfax, where 36 million olive trees have been planted and are already yielding over 2 million tons of oil a year,

The area of this vast underground reservoir extends more than 650 000 square kilometres - the size of France. In some places it may be 90 metres deep. but in others from 500 to 2 000 metres. Justin Savorin called the Alb the finest hydraulic device in the Sahara; and because he did more than anyone else to explore it, the Saharans know it as Savorin's sea. Savorin estimated that the Alb contained over 10 million cubic metres of water. An hydrologist has estimated that it would take the Rhine almost 190 years to fill a reservoir of that capacity.


Our first study of the western and northern countries of the Sahara began in 1952 with Morocco when we had the opportunity of studying their nursery practices, plantations of eucalypts of various ages under different conditions, and an arboretum or eucalyptum of some 30 species being studied for their suitability. On an excessively eroded hillside where too little soil remained to establish eucalyptus, prickly pear cactus was being planted and frequently cut back and left to decompose to form a humus paving the way for the establishment of eucalyptus plantations. Later, in 1957, Sultan Mohammed V inaugurated the youth forests. He merely had to ride up a hill when he would be followed by thousands of young planters kept well supplied with lorry loads of transplants in polyethylene bags, and in his horse's footprints a forest arose; 36 000 people offered themselves and an average of 10 000 were at work planting trees over the weekends. Five months after planting one youth forest many of the trees, Eucalyptus camaldulensis, had grown over 30 centimetres a month. This was at Bu Soukra where 140 hectares had been planted with 80 000 trees on Sundays. The Governor of Casablanca had set a good example, taking off his coat and wielding a planting mattock with the rest.

It is fortunate that the Koran teaches respect for trees and makes special promises to planters of trees. but the goat is still the bête noire of the forest. It is no small task to educate people among whom flocks and herds have been regarded as wealth, to turn from an animal to a silvan economy.


In Algeria the principal ways of -protection put into effect included the banquette system, with small banks; running at right angles to the slopes, descending like steps down the hillsides. They are protected from the upper extremity by a canal, diverting the water, furrowing the slopes in an almost horizontal network. Their cross section comprises a bottom which is flat or inclined upward, and an embankment which ensures that the mitigated flow of the torrential rain runs toward a natural outlet. The bottom of the banquette aerated by cultivation absorbs a fair amount of water, while it increases friction of the longitudinal stream which is able to establish itself and facilitate the deposits of the small amount of the material that comes from the banquette above. When the hillsides are too steep to grow cereals they are planted to trees such as aleppo pine, carob or olives. Each perimeter, each sloping basin, each piece of ground to be treated, becomes the object of a comprehensive plan which determines the method applicable to each part and leads to a combined use of different methods of treatment.

FIGURE 6. - Marginal palm, growth near Hun. Moving sand dunes are a threat even to the palm tree.

In Algeria I have since been impressed by the enthusiasm of young planters who devoted their weekends to repairing the ravages of war when so much damage was done to the cedar forests. Indeed, tree planting seems strongly associated with patriotism and love of their country, as it should be everywhere. It was in Algeria that an experiment in transpiration showed that a single Eucalyptus algeriensis, 14 metres high, transpired as much as 370 litres of water every 24 hours. Thus a forest of such eucalyptus trees would create a microclimate of appreciable influence. Rain-bearing winds from the sea would naturally be reinforced by such transpired moisture and tend to create clouds and precipitate dew or rain.


Foresters in Tunisia have demonstrated the value of the ridge system of planting devised in Algeria. To this ridge system has been added a method of using plastic bags for raising the young transplants. To release the roots from the bags the plastic is slit with a sharp knife or razor blade and after the young tree is planted the plastic is spread on the ground, a slit being made in the centre to allow the leading shoots of the young trees to come through. Afterwards swift touches are given, firming the earth with a slope toward the tree, before the plastic is covered with about 1 centimetre of soil. It has been found that, while allowing any rain to penetrate through the top slit, this plastic sheet prevents excessive evaporation of moisture and gives the transplant a good start. Watering is by injection under the soil direct to the roots with an exaggerated hypodermic needle. The moisture thus injected connects up with the capillary moisture. It is claimed that the first and only injection of water remains around the plant for many weeks, and the soil on the surface does not harden.

The reforestation institute set up by the Government of Tunisia at Ariana has been operated by FAO since 1965 with the help of funds of the United :Nations Development Programme (UNDP). It is now one of the most active research organizations in the country with over 30 arboreta. Another research station is in operation at Zerniza, in the northwestern coastal region.

One of the most spectacular plantings in Tunisia may be seen at Sfax where 36 million olive trees have been planted on sand dunes each in its own depression. These trees are already yielding nearly 2 million tons of olive oil a year.

FIGURE 7. -Successful dune stabilization has stopped the encroachment of sand near another clump of palms.


As in Tunisia so in Libya both Acacia and Eucalyptus grow vigorously shortly after planting, establishing firm roots and forming their own windbreaks. The Acacia becomes commercially useful at from 10 to 15 years and E. camaldulensis at from 15 to 20 years. The conventional method of planting is known as dissing, forming small hedges of grass to provide protection for the moving sand dunes, though this has to a great extent been superseded by spraying an oil mulch over the area after planting. Whenever there are moving sand dunes they threaten cultivations and even palmeries.


Since 1953 I have witnessed the remarkable rehabilitation programme in the United Arab Republic; in Tahrir Province land that has been desert for 2 000 years is now coming into full production with the help of shelterbelts of Casuarina, Eucalyptus of many varieties, Acacia arabica and Tamarix articulis, both drought resistant and tolerant of salinity in the soil. Over 400 hectares will eventually be brought into this reclamation programme providing thousands of new farms and absorbing many Arab refugees. Huge cement, canals bringing water from the Nile, with a network of smaller ones, are used to irrigate the land and pro" vice fish for food. Mud has been brought with aquatic weeds, and Tilapia nilotica from the Nile, Tilapia galilea from the sea of Galilee, and Tilapia zillii from Lake Victoria Nyanza have been introduced. The bottom layer feed on the aquatic weeds, the middle layer feed on the spawn of the bottom ones and the top layer on the fry of the middle ones and themselves are lifter'! out in tons for human food. I have also visited the New Valley project consisting of a series of depressions III the Western Desert covering an area estimated at 4 to 5.6 million hectares, and seen 30 of the 150 gushers at Dakhla where water was rising under pressure from a depth of 1 100 metres with such power that the electronic computer gave it 200 years before the necessity for pumping will arise.

I am not so happy about the high dam of Sadd El Aali, for the evaporation over the 500 kilometre-long lake it will form will be equal to the amount that reaches the crops. The vast pressures may form a sump in the bottom allowing an ever-increasing volume of water to escape and join the subterranean Nile whose waters at present are largely lost in the Mediterranean Sea.

FIGURE 8. - Shaping banquettes with a caterpillar tractor or terraces after a rooter had torn. up the soil. Beni-Saf, Algeria.

FIGURE 9.- A few of the many Arab refugees who are finding new farms and homes in the Tahir Liberation Province, some 140 kilometres northwest of Cairo.


Each time I have returned to Ethiopia, Kenya and the Sudan steady progress has been made in land reclamation and tree planting. Perhaps the most spectacular planting is in Kenya, where President Kenyatta is patron of the Men of the Trees and has inaugurated national tree planting weeks. The Kenyan Forestry Department has an enlightened and progressive planting policy.

In Ethiopia it was Menelik II who, when Addis Ababa was threatened with a wood famine, had the good sense and foresight to introduce into the area fast-growing eucalypt trees from Australia instead of moving his capital to a wooded area, as was the custom in those times. He presented young trees to his chiefs and elders who in turn raised trees for new seeds, and Addis Ababa was saved. His successor, Emperor Haile Selassie, has given his patronage to the Sahara reclamation studies and is himself encouraging a progressive planting programme in Ethiopia in which the perpetuation of indigenous species is not neglected.

Assistance by foreign commercial companies

It is encouraging to see how some of the petroleum companies have taken up the challenge of the Sahara. After several years of laboratory work and field experiments, ESSO in 1960 began experiments in Libya using a petroleum product to stabilize drifting dunes and assist growth of transplants. Initially spraying was done by hand using conventional tankers mounted on specially designed chassis. The latest is a toboggan-like vehicle towed or winched over the dunes by a caterpillar tractor. Sliding on the sand as a sled moves over snow, the unit carried cargoes in excess of 10 tons over some of Libya's most challenging dunes. It is estimated that 250 000 hectares in western Libya alone are suitable for afforestation using Acacia and Eucalyptus.

Another new method of large-scale afforestation in dune areas is in the process of being developed by an Austrian firm, Agrarflug-Glück; in February and March 1969 I visited Libya to study this latest effort to stabilize the drifting dunes and at the same time afforest with quick-growing species that will afford permanent protection and help to bring back natural vegetation. This method is by direct seeding from low flying planes using a fixative which has more or less the same function as an oil covering but with this difference-the chemical mixture used, derived from lignin, is a natural product and greatly stimulates the growth and function of the natural vegetation.

Perhaps the most sensational news from the Sahara is the discovery by Occidental Petroleum Corporation of an aquifer at Kufrah several hundred square kilometres in area and at least 750 metres deep. In some places it lies 90 metres below ground level. Since March 1968 five new wells have been drilled, the first crops were planted in October and harvested in January 1969. It is estimated that the Kufrah find will enable Libya to irrigate 80 000 hectares for the next 200 years. It is hoped that indigenous trees assisted by the soil improving casuarinas will create microclimates favourable to crop production and provide necessary fuel for the Libyan farmers who had been forced by the oncoming desert to move to Lake Chad and who are now coming back to Kufrah in droves. The 10 000 hectares already irrigated are producing wheat, alfalfa, barley, tomatoes, potatoes and beans, demonstrating -what can be achieved over ever-widening areas.

FIGURE 10. - Spraying toboggans designed by ESSO, towed by caterpillar tractors across the most difficult dunes.

FIGURE 11. - Twenty-four month old tree at Khallet Al Shorrfa, east of Tripoli, an area of sand dunes sprayed and stabilized for the Libyan forestry department by ESSO.

After forty years

At the Sixth World Forestry Congress in Madrid in 1966 participants from 92 countries supported proposals for calling upon all states members of the United Nations to use their manpower for large-scale planting; that the protection given by adequate tree cover be treated as a first line of defence, and that total war be declared against the oncoming deserts of the world. Forty years had taken their toll of delegates since the First World Forestry Congress in 1926 and on the final day of the Madrid conference only three of them answered the roll call - one American forester, one Spanish and myself, a veteran forester from Africa.

When visiting FAO recently I had the pleasure of meeting many old friends of past safaris and those who had closely cooperated with us in connexion with the Sahara reclamation research and studies. This visit inspired these flashbacks to the small beginnings of what I hope may become one of the most momentous events in the story of Africa. The Sahara affords a challenge not to Africa alone but, to the world. It, offers a glorious opportunity to sink the political differences and past exploitations of our planet into a new creative economy, a new way of living, a biologically correct way of life bringing health and security. The task is a gigantic one and it cannot be achieved overnight. It will need the dedication of generations of foresters and land reclamationists.

If our knowledge challenges us to explore space and put a man on the moon, let our wisdom lead us to accept the challenge of the Sahara and help the new states of Africa make it once again a garden wherein millions of people may live free from fear and hunger, in peace and prosperity- "Every man under his own vine and fig tree, with no one to make him afraid."

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