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Overcoming the major obstacles to tree planting

Environmental Constraints

As in India, the major environmental constraints in Kenya are high temperature, low rainfall, and soil characteristics (depth of rooting zone, alkalinity/salinity). Human resource constraints and the lack of meteorological data imply that accurate determination of the degree of aridity can be done in only a few places. However, a greater problem in the ASAL of Kenya is the erratic nature of annual precipitation. Not only does this imply very low precision in establishing isohyets (e.g., figure 2) but, more important, it necessitates repeated trials of species and afforestation techniques over several years. Results of survival and growth from a trial in a year of relatively abundant moisture cannot be extrapolated reliably to years of relative drought.

FIG. 9. Some Causal Factors in Desert Encroachment in Northern Kenya (based on Lamprey 1978)

Because of the natural and man made scarcity of vegetation in the ASAL and the poor texture of the surface layers of the soil, rainfall is often not conducted to deeper soil layers for storage and use by plants but is lost as surface run off with consequent erosion. These problems could be mitigated by the re establishment of vegetation and by the use of planting and cultural techniques that conserve the limited precipitation and make it available to the tree crop.

Because afforestation in Kenya to date has been con centrated in the high rainfall areas, there is little experience in planting in the ASAL. Consequently the various pitting, ploughing, subsoiling, terracing, and other ground preparation techniques that are established elsewhere (see chapter 2 or Ghosh 1977 for examples from India, or Delwaulle 1979b) have not been evaluated fully.

It is true that the systems developed in one region, country, or district are not necessarily optimum in another area, but they may be good starting points for research and development. The low agricultural productivity of the ASAL and the relatively low density of the human population suggest that methods of site preparation and tree crop establishment that are traditional elsewhere (such as the taungya or shamba systems) will not be suitable. Further, as Owino (1980) pointed out, the soil conditions in arid areas dictate that soil disturbance be minimized so that minimum tillage if not zerotillage methods are ecologically appropriate, although water conservation measures will be necessary, including post-planting weed control to minimize competition for limited water supplies. Mulching, including woody mulch, is also promising (Huxley 1981). On the other hand, as stressed by Delwaulle (1979a), the variation in soil type is so great over small distances that typical pure plantations do not capitalize on the site potential and are less productive than mixed crops, indicating that agro-forestry combinations may be the optimum land use despite the added competition for water. The range of crop combinations, spacings, and cultural methods (described for India in chapter 2) must also be evaluated in Kenya.

Whatever the ground-preparation method adopted, it must be timed to coincide with the onset of the rains and, if any form of artificial irrigation is to be contemplated to allow pre rain planting, it must be given in a form and frequency to encourage the natural pattern of root growth of the tree species. However, in many areas at the end of a dry season, water is often not available in sufficient quantities for humans and domestic animals so that pre rain irrigation of trees is unlikely to be feasible. Barrow (1980), a missionary noted for his trials of tree and agricultural crops near Nginya (Baringo), has suggested that deep planting holes with microcatchments (i.e., ridges surrounding saucer-shaped depressions, see fig. 6), should be prepared to collect 50-100 litres of water from the first rains, which would act as a reservoir facilitating tree survival and growth when planting is carried out at the second rains (some two to four weeks later); this technique has had considerable success.

The problem of tree planting on saline soils is similar to that encountered in India (chapter 2), but less is known in Kenya of the distribution and management of such soils. Fewer resources (of water, staff, engineering, or finances) are likely to be available for large scale flushing or soil amendment, and the most likely approach is the choice of salt-tolerant species. In the United Kingdom's proposed technical assistance project, a research station on saline soils is suggested for Isiolo.

Technical Obstacles

Nursery and Plantation Techniques

The technical obstacles form the group of constraints to tree planting that can be most easily overcome Techniques for raising nursery stock for subsequent out planting are reasonably well known for the ASAL (see chapter 2 and Ghosh 1977; Goor and Barney 1968; Kaul 1970; Synnott 1979; Weber et al. 1977) although they are not apparently widely known in Kenya. They are based mainly on polythenetubed seedling stock, cuttings, or stumps. For each species and major site type the optimum morphology of planting stock neds to be determined; although tube size should be minimized to reduce transport and handling costs, it must not be so small that out-planted stock are too small to survive. Also the common practice in wetter areas of root pruning to induce a fibrous, compact root system without a tap root may not be applicable to plants for the ASAL in which a strong tap root is desirable to seek the limited moisture at great depths in the soil. Research is needed into the feasibility of using growth retardants in the nursery to improve pre-planting hardening and antitranspirants for reduction of post-planting water requirements.

Ground preparation and crop cultural techniques already known to maximize water availability were discussed above in relation to the environmental constraints. These have not been assessed in Kenya, and research and development are needed before adequate extension advice can be given. Mulching with organic material would decrease weed competition and increase the water holding capacity, and it is likely to be practical even in arid areas that are already sparsely vegetated provided that woody mulch is used.

Disease and insect protection may be required in future for plantations, and protection against fire and domestic animals (see below) will certainly be needed in the ASAL of Kenya, thus adding to the costs.

Virtually nothing is known of the costs and benefits of nursery and field operations, and these will undoubtedly vary with the site, species, techniques, and labour available. It is essential to have this information precisely estimated for appropriate appraisal of land development projects. Distinction must also be made between revegetation projects (planned mainly for soil and water conservation with no premium on forest products and in which many species should be incorporated to maximize the chance of some usable products) and afforestation or agro-forestry projects (with one or several end products required from fewer tree species either pure or mixed with agricultural crops or pastures); both requirements exist within the ASAL of Kenya.

Species and Provenance

A large number of species have potential for planting in the ASAL of Kenya. Notable successes have been achieved in other African countries and some species have already succeeded in arid areas of Kenya itself. Owino (1980) listed 33 species, but his definition of the arid areas included those with annual precipitation of 250- 1,150 mm; Synnott (1979), however, described some 77 species or genera with potential in the ASAL of northern Kenya (up to 600 mm rainfall) and also classified them by site adaptability, uses, and livestock palatability. The UNESCO/ IPAL project established 49 taxa of trees, shrubs, and herbs at 11 fenced stations in three ecological zones, and after one to three years six species show promise. Other species were listed in Delwaulle (1979c, 1979d) and in the many references given in chapter 2.

Together these reports offer a large number of possible species, but this large choice is itself a constraint. First, it is difficult to obtain seeds or other propagules of many of the species and their provenances; for some of them even the nomenclature and taxonomy are confused. Second, little is known in Kenya about correct seed handling for many species. Third, even if these first two problems were overcome, it would be a major technical and managerial task to undertake the design, management, and evaluation of systematic trials of such large numbers, particularly if many provenances are available. Fourth, the "pickthewinner" approach is wasteful of resources.

The large number of potential species and populations should be reduced on the basis of ecological comparability, physiological understanding of drought and salt tolerance, and experience elsewhere. It was shown in chapter 2 that in India a large number of species and provenances have been systematically tested and a few chosen as having great promise. Some of these will undoubtedly be of value in Kenya, and Kenya should participate to the greatest extent possible in the FAO/IBPGR international trial of tree species for the arid zone with replicated trials on a large number of sites. These may be in the areas assigned to individual bilateral and multilateral assistance projects but should be centrally co-ordinated and evaluated by the silvicultural research staff of the Kenya Forest Department and KARI. The facilities at KARI should be upgraded to facilitate the selection, storage, distribution, and documentation of seeds.

Economic, Social, and Institutional Problems

Sources of Wood

It was shown above that actual consumption of fuelwood alone within Kenya may be as much as one thousand times the officially recorded consumption, although the estimates of Kamweti (1979) were somewhat higher than those of Western and Ssemakula (1979) and certainly higher than those cited by Hall (1980) and Howe and Gulick (1980). Whatever the exact figure, it is clear that vast quantities of fuelwood are being removed (largely from areas outside forest reserves), that demand is increasing as the population increases (at a rate that is virtually the highest in the world), and that both urban and rural demand are such that transport distances have increased between growing area and user (increasing the need for conversion of wood to charcoal).

It is true that all these contribute to the removal of forest and tree cover with no attempt at artificial replacement and the consequent damages of desertification. Until recently the cost of fuelwood in most urban and some rural areas equalled or exceeded the costs of kerosene or butane, which mitigates against further use of wood. However, traditional methods change slowly, and it may be more effective to offer cheap, efficient wood-burning stoves than to rely on a further massive swing to the use of butane or kerosene. As shown by Openshaw (1980), the substitution of non-renewable energy is neither economically nor practically feasible, and renewable energy sources such as biogas and solar heaters are at best only partial solutions. For the Machakos area discussed by Openshaw and for many other parts of the ASAL, the simplest and most practical solution is to guarantee the fuelwood supply by investing in plantations, woodlots, and agro-forestry. However, it should be noted that the study by Openshaw understates the costs and overstates the benefits to farmers of growing fuelwood by giving it a value equal to its price in Nairobi.

Cultural Attitudes toward Wood

Wood is often said to have been a free product in the past, but careful attention has to be given to how "free" was defined by the local people. Depending upon the society, access to land and trees were sometimes formally defined, with access determined by whether one was a member of a particular group. For example, to have rights of access and of gathering wood in a certain area one would have to belong to a particular lineage or other kinship group. Although some Kenyan agricultural societies are said to have been important agents of deforestation in expanding their settlements and farms, these groups sometimes formally recognized the value of trees. Leakey (1977), in his study of the pre-colonial southern Kikuyu (often said to be one of the most active groups in causing deforestation) points out that local councils sometimes set aside forest areas to be protected and maintained.

Wood is also a crucial resource for pastoralists. Many stereotypes of pastoralists exist, with some viewing them as "sons of the desert," while others suggest that "fathers of the desert" might be more accurate. In a recent study of the Masai, Western and Dunne (1979, p. 75) found that they have a "sophisticated knowledge of the environment," and the Masai "exhibited an appreciation of environmental processes and characteristics." These generalizations can probably be applied to other pastoral groups.

Western and Dunne emphasized that the presence or absence of vegetation is an essential element in settlement site selection among the Masai. No settlement is possible in areas devoid of woody vegetation because materials are needed for construction and fuel (Western and Dunne 1979, p. 92). At the same time densely vegetated areas are not favourable because of danger from predators. Western and Dunne also state that settlements generally are located near a good supply of wood because demand for it is so substantial and that collection efforts might be minimized. The Masai recognize particular values of trees and bushes:

Firewood is selected on the basis of its hard, dry qualities to provide a long burn with minimum smoke emission. Many species fulfill these criteria, but there is nevertheless a conscious selection. Because fuel demands are low compared to the amount of material needed in the construction and maintenance of the settlement fence, relatively long trips (to supplies) are possible and settlements are usually closer to construction materials than to firewood.

Choosing different settlement sites during seasonal and yearly migrations allows vegetation to regenerate.

Some observers suggest that the concept of wood as a free product inhibits tree-planting efforts, since people do not perceive wood as being scarce. The time and labour of women and children who collect most of the wood are not seen as having a cost by the local people. Such a view fails to take into account some important socio-economic changes at the local level. Land adjudication has meant the privatization of property. Even if wood itself is not scarce, the privatization of land means that access to available wood supplies is being curtailed. In some areas adjudication has resulted in confusion at the local level rather than in a simple restriction of access, but the privatization of land appears to be the dominant trend. Once people begin to plant cash crops, a concept of the opportunity cost of labour soon develops.

In some areas private landowners are recognizing the scarcity of wood and are planting trees to meet future needs. These plantings have been spontaneous and not the result of Government efforts. As mentioned previously, there are among some groups cultural precedents for tree planting and protection.

Perhaps more an obstacle to tree planting and protection than the perception of wood as a free product is its perception as a source of income. Wood fuels have become commercialized in many areas, and with a rapidly growing urban and rural population this trend is likely to continue. The improvement of transport facilities has linked the rural hinterland with commercial networks. Many rural dwellers, especially the poor, see the sale of wood fuels, particularly charcoal, as a supplementary source of income. The presence of a market thus creates an incentive for consuming resources as fast as possible and without regard for future needs.

Some of the commonest errors in identifying and planning rural community or household-level forestry projects arise precisely from such failure to perceive and understand what are the real costs and benefits to those involved. As in India, there is a lack of dissemination of anthropological information that might help to explain why changes take place and their impact on the people concerned (see, e.g., Brokensha and Riley 1978).

With good management the best tree species will require five years or more in the ASAL to Yield significant quantities of products (even with coppicing for fuel or pruning for fodder). Good management includes ground preparation and post-planting protection (against fire, rodents, domestic animals, and humans themselves). These in turn require security of land tenure. Yet for much of the arid zone of Kenya, as well as the Sahelian zone of Africa and the arid lands of other continents, nomadism, transhumance, and pastoralism are the major land uses, and common land is the major form of tenure. As we have noted, 20 per cent of Kenya's 15 million people live in the ASAL (82 per cent of the total land area). Although local (unofficial) councils of elders make decisions on the use of grazing lands, only a few of the official district councils have set aside areas of common land for tree planting.

Pastoralism, Nomadism, and Land Tenure

Some observers suggest that settling nomadic and transhumant pastoralists might be necessary if tree-planting efforts are to succeed. Past experience with various grazing schemes and group ranches demonstrates that settlement schemes often end in ecological and economic disaster. Desertification by overgrazing, soil compaction, and deforestation around the village may create even more problems than existed previously. Moreover, such a scheme is usually based on the premise, shown to be false in the preceding section, that pastoralists are irrational managers of natural resorces. Numerous studies (Dyson-Hudson 1980; Fumagalli 1978; Gulliver 1955; Helland 1980; Hogg 1980; Schneider 1974; Swift 1975) have convincingly documented the rationality of pastoralism. For a tree planting scheme to work, planners and foresters must work with the pastoralists, not against them.

Because most observers have strong views about pastoralists, and because of the sharp divergence of such views, it is worth amplifying these remarks. Many administrators and planners have a pronounced anti-nomadic bias, in part because nomads are seen as inefficient anachronisms and in part because settled peoples often perceive nomads as a threat. Thus administrators are often ready to blame the stupidity and conservatism of pastoralists as reasons for development failures, while anthropologists hasten to explain how pastoralists' behaviour is really rational and an effective adaptive strategy to their hostile environment. As Chambers (1977, p. 2) recommends, what is needed is a systematic approach that combines research, consultation with local people, and training.

Several detailed studies have recently been made of pastoralists in Kenya (for an excellent review of the literature on "Nomadic Pastoralism," see Dyson-Hudson 1980). Dahl and Hjorts (1976), Baxter (1975), and Hogg (1980) have all made intensive studies of pastoralists and their economic systems They conclusively demonstrate that most present strategies are rational, that pastoralists will consider and adopt agriculture in the right conditions, and that, far from being resistant to change, the herders readily accept innovations and new investment opportunities when these are available.*

The Cattle Economy vs. Monetarization and Markets

Because of the harsh ecological conditions and limited production capacity of the land in the ASAL, relatively little area exists under agricultural crops (although with increasing populations more marginal land is being cultivated) and livestock raising is the principal source of livelihood and is the basis of the economy. Traditionally large numbers of animals are maintained as insurance against loss in periodic disasters such as severe droughts, and these numbers are increasingly exceeding the carrying capacity of the land. This capacity itself has not been adequately studied, but there is an urgent need to determine and maintain a stable equilibrium and Konczacki (1978) suggests a model of pastoral economy that includes the basic conditions for the achievement of that equilibrium. He concludes that to achieve the equilibrium and to maintain pastoralism as a way of life requires outside intervention, including introduction of insurance schemes, reform of land tenure systems, and provision of alternative employment. The widespread planting of tees would offer the third of these requirements and provide for the first, given that the second can be ensured.

In planning development for African pastoralists a major problem is that livestock production hitherto has been practiced for subsistence, not for markets. (See, e.g., Helland 1978.) The economy is essentially not monetary, and sales and marketing systems are poorly developed. Cattle are rarely sold, except under extreme duress, and other products do not enter into market streams except in close proximity to major villages; even here road and transport systems are primitive. The planting of trees is inhibited initially by these constraints, yet at the same time trees could offer means of developing a monetarized economy (and hence marketing and transport systems), particularly through their yields of multiple products, especially fuelwood and fodder. However, this is not substantiated by the present study, and further work is required to focus on the social science aspects of involving nomads in tree planting.

Integrated Land Management

Given that, for obvious reasons, the high-potential areas have been emphasized first and also recognizing that the ASAL must now receive its fair share of attention, the urgent need is for an integrated approach to development involving agricultural and forest departments together with the provincial and district planning authorities. These authorities and financial assistance agencies still require precise estimates of costs of establishing trees in various farms, woodlots, and plantations. For village woodlots, World Bank estimates range from US$300 to over US$1,000 per hectare including the first five Years' maintenance, although Howe and Gulick (1980) quote significantly lower figures for some African villages. Without initial national Government or international assistance, rural communities will obviously be unable to finance major ventures of this type. The relationships of the various factors contributing to desertification are illustrated in figure 9, and suggestions for the development of multiple land use to combat these problems were given by Maydell (1978a, 1978b, 1979) for the Sahelian zone of Africa and are relevant to the Kenyan ASAL. However, these require a rational approach to the use of communal land that has not yet been developed in Kenya although, according to Spears (1978), in some parts of Ethiopia, Nigeria, Rwanda, and Tanzania, rural communities suffering from wood shortage have begun voluntarily to set aside marginal areas such as hill tops and slopes for afforestation.

Staff and Training

Even in the less arid areas, where more permanent agriculture is practiced, distances between administrative centres are great; trained administrative and educational staff are limited; policy makers do not perceive the severity of the problem; and housing and communications are poor. Above all there is a marked reluctance among professionally trained foresters to work in the ASAL. It is a regrettable but common feature of developing countries that professionals prefer to work in capital-city offices rather than in the field (and this is already apparent in Kenya with the declining standards of nursery and plantation practice in existing forests), and in Kenya they prefer to work in the high-potential areas rather than the ASAL, particularly avoiding the north. This of course largely reflects their origin and in turn reflects the former concentration of populations and education in the more productive areas. Further, the problems of arid zone development have not been considered seriously in professional and technical courses to date. To undertake the research and development that is required for widespread tree planting in the ASAL, a major revision of existing curricula is required, and a highly suitable core curriculum has been developed for the University of Nairobi's Department of Forestry by Professor N. Kissick. This is being discussed by the university authorities, and it should receive high priority. It includes are high temperature, low rainfall, and soil characteristics (depth of rooting zone, alkalinity/salinity). Human resource constraints and the lack of meteorological data imply that accurate determination of the degree of aridity can be done in only a few places. However, a greater problem in the ASAL of Kenya is the erratic nature of annual precipitation. Not only does this imply very low precision in establishing isohyets (e.g., figure 2) but, more important, it necessitates repeated trials of species and afforestation techniques over several years. Results of survival and growth from a trial in a year of relatively abundant moisture cannot be extrapolated reliably to years of relative drought.

TABLE 8. Kenya Personnel Training Needs (1981-1990)

Public sector  
i. Rural afforestation in 40 districts out of the
existing 57 including forest management
needs = 40 x 3 =
ii. Research staff for the 5 stations of Muguga,
Turbo, Mombasa, Hola, and Kibwezi
(30 M.Sc. + 15 Ph.D)
iii. Training-appointees for the Department
of Forestry (M.Sc. level)
-teachers for the Londiani Forest Training
School (M.Sc. level)
iv. Regional programmes - 10 programmes are
already working, some of which are
listed below:
Tana River Development Authority
Lake Victoria Basin Development Authority
Kerio Valley Development Authority
Baringo Valley Development Authority, etc.
10x 2 =
Total public sector
Private sector
i. Factories and timber industry 15
ii. Small-scale mills and prefabricated housing 15
iii. Undetermined Yet 0
Total private sector 60
Total public and private sector 268
Additional needs  
i. Wastage, 5 per cent; retirement and
resignation, 5 per cent
ii. Foreign students, 10 per cent 6
Grand total 320

Source: Ministry of Natural Resources (Forestry Department),

Faculty of Agriculture, World Bank the course on agro-forestry outlined in Appendix II. ICRAF has already been concerned with agro-forestry training in Kenya through its joint sponsorship of a national seminar (with Nairobi University).

The existing facilities and size of staff (four permanent lecturers) in the university's Department of Forestry are wholly inadequate for the numbers of students and type of course required. However, the fifth World Bank education project currently being appraised includes provision for major expansion of the department's resources to meet the proposed annual requirement of 50 graduates. The composition of this manpower projection is shown in table 8.

It should be noted that a recent high-level projection of personnel requirements by the Kenya Ministry of Natural Resources indicates that Kenya needs 20-30 graduate foresters per Year to be trained for the next five years for employment in the public sector. According to the same source, the high-level staff needs in the private sector are expected to be in the region of 10 to 15 graduates per Year for the next five years. In light of these figures, 30 to 40 graduates per Year will be necessary to meet the needs of the forest sector, including in-service training. However, the physical facilities of the Department of Forestry will be planned up to an intake of 50 per year so as to meet long-term needs, including the possible increasing needs of the private sector and training of wildlife management.

Even if these numbers of professionally trained foresters are produced, there will still be an urgent need for specialized training in research, project planning, and rural extension. In these requirements Kenya is no different from India-it can ill afford to lose the services of staff for the two or three years necessary to obtain post-graduate degrees. The intensive short courses outlined in Appendices I-III would be suitable.

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