Part II
COUNTRY BRIEFS (continued)

HAUTE-VOLTA (continued)

Bibliographie

1. Terrible, M. 1975 “Essai d'évaluation de la végétation ligneuse” - in Atlas de Haute-Volta - Centre Voltaïque de la Recherche Scientifique/Services Forestier, de l'Environnement et de la Protection de la Nature - Ouagadougou

2. Service forestier 1976 “Résumé de la situation forestière en Haute-Volta” - Rapport présenté à la Consultation sur le rôle de la forêt dans un programme de réhabilitation du Sahel (Dakar, 26 Avril–1er Mai 1976)

3. Terrible, M. 1976 “Carte et notice provisoires: végétation de la Haute-Volta au millionième” - in Contribution à la connaissance de la Haute-Volta - Bobo- Dioulasso

4. Kambou, M. 1977 “La Haute-Volta - La forêt” - document présenté dans le cadre du Stage pratique d'échanges et d'expériences dans les domaines forestier et industriel (Abidjan, 13–24 avril 1977)

5. Jeune Afrique 1977 “Les Atlas Jeune Afrique - Haute-volta”

6. Programme de coopération FAO/Banque mondiale 1977 “Sahel central - Mission de reconnaissance forestière” - Rapport No. 17/77 - CESA.1 - Rome

7. Ministère de l'environnement et du tourisme 1978 “Commission des forêts pour l'Afrique-Rapport de la Haute-Volta”

8. Programme de coopération FAO/Banque mondiale 1978 “Haute-Volta - Projet de reboisement - Mission de préparation” - Rapport No. 28/78 - UPV 3 - Rome

9. FAO 1979 “Développement des ressources forestières et renforcement du service forestier - Haute-Volta - Apports des collectivités rurales à la mise en valeur des ressources forestières” - sur la base des travaux de J. Devillé - FO: DP/UPV/78/004 - Rapport technique 1 - Rome

10. FAO 1979 “Note sur la forêt classée de Toumousseni” - par J.J. Samyn - Projet forestier UPV/78/004 - note de travail - Bobo-Dioulasso

11. FAO 1980 “Carte forestière: première esquisse” - par A.G. Cameratti - Projet forestier UPV/78/004 - Memorandum, carte et note explicative - Ougadougou

12. FAO 1980 “Ressources forestières - Haute-Volta” - Commentaires par M M. de Backer et Cameratti sur le résumé rédigé par le projet FAO/PNUE d'évaluation des ressources forestières tropicales - Ougadougou

KENYA

Kenya is situated approximately between parallels 4°40'N and 4°40'S and meridians 34°E and 41°E, and extends from the shores of Lake Victoria to the Indian Ocean. Its total area is 580 367 km² of which 11 230 km² is water and 569 137 km² is land surface.

The country is split by the Great Rift Valley, which is about 60 km wide and up to 330m deep. A large part of this valley is occupied by range lands. The region at the east of the Rift Valley lies at about 2 000 m above sea level and is dominated by Mount Kenya (5 230m), the highest mountain of Kenya, and by the Aberdare mountains¹, reaching almost 4 000 m. In the west, the country slopes down to Lake Victoria, but this side shows also the mountains of the Mau Range, and Mount Elgon (4 320 m) on the border with Uganda.

The highlands, forming most of the south-west and central parts of the country have an elevation from 1 400 to 2 800 m above sea level, and are well watered and fertile. On the contrary more than half of the northern and north-eastern part of Kenya is subdesertic.

Rainfall ranges from less than 200 mm in the semi-desert parts to 2 300 mm or more on the high elevations. The forested areas receive more than 750 mm of rainfall. East of the Rift Valley two rainy seasons occur (March–May and November) and to the west only one (April–September). The south-west monsoon (“Kusi”) blows from April to August.

The population can be estimated at about 15.7 million in 1980 and is growing at a rate of 4.0% per year, according to the 1979 census.

¹ Now called Nyandarua range

1. Present situation

1.1 Natural woody vegetation

1.1.1 Description of the vegetation types

The climax forest was more widely distributed before cultivation and burning reduced it to its present state. Most of it lies above 2 000 m with only few large blocks below this elevation. The following description of the woody vegetation is derived from (12) and presented according to the broad categories of this study.

Closed broadleaved formations (NHC)

Only small remnants are left of the coastal forests on the wetter soils of the hills and along the rivers. Below 350 m, on sites with more moisture, occurs a mixed evergreen forest with abundance of Afzelia and Trachylobium species.

At higher altitudes (over 1 500 m), in the south-west, the Teita Hills, are covered by an evergreen forest with camphor tree (Ocotea usumbarensis). Mt. Kasiagu has a small area of forest near its summit; Newtonia buchanani is predominant between 1 300 and 1 600 m.

Mangroves are scattered along the coastal belt on the inter-tidal zones on estuaries and along creeks. The two principal species are nikoko (Rhisophora mucronata) and mkandaa (Ceriops tagal); four other (non-merchantable) species are also present (8).

The upland forest belt in the wetter zones begins with the plateau forests, between 1 300 and 2 000 m, and occurs in the central part of the country (neighbourhood of Nairobi, Ngong, Kiambo and Nyeri), with an annual rainfall of 850 to 1 000 mm and a cool and equatorial climate. These forests are evergreen or semi-deciduous. The evergreen type is dominated by Brachylaena hutchinsii (muhugu) and Croton megalocarpus. The semi-deciduous type is less rich in species.

The largest areas of upland forest occur on the main mountains between 2 000 m to about 3 500 m: Mt. Kenya, Mt. Elgon, the Aberdare range, the Laikipia escarpment and the Mau-Elgeyo-Cherangani mountain system. This evergreen forest can be subdivided in the following types:

• forests dominated by Ocotea spp.: the most important species is O. usambarensis (east African camphor tree), a large tree up to 45 m high, often associated with Myrica salicifolia. These forests occur on very dissected terrain. The lower parts of the valleys and ravines may contain Syzygium sp., Ilex mitis, Ficalhoa laurifolia, Ensete vertricosum and tree ferns. The Ocotea forests present regeneration problems, as the seeds are threatened by predators, and the suckers by elephants;

• within the altitudinal range between 1 500 and 2 400 m the Aningeria adolfi friederici forest occurs in the wet montane zone. Aningeria is associated with Albizia spp., Alangium chinense, Allophylus abyssinicus, Casearia battiscombei, Tabernaemontana sp., Croton macrostachys, Syzygium guineense and others.

On the south-west and north-east of Mt. Kenya and in the north-eastern Aberdares the pilar wood (Cassipourea malosana) forest occurs. Tree species in the canopy (9–21 m) include also Albizia gummifera, A. schimperania, Fagara sp., Hagenia sp., Ilex mitis, Macaranga kilimandscharica, M. conglomerata, Ocotea usambarensis, Prunus africana, Rapanea rhododendroides.

Open broadleaved forests (NHc/NHO)

The upper zone of the upland forest belt usually consists of woodland from 12 to 18 m high. The Hagenia-Rapanea type is common under wet conditions, and may be replaced by Afrocrania-Aguaria woodland in drier areas. Around 3 200 m, the Hagenia abyssinica woodland (up to 18 m) forms a belt which, under favourable conditions and minimum disturbance, might extend up to 3 500 m. In this altitudinal range the only other tree species are Faurea saligna, Prunus africana and Rapanea rhododendroides.

In the southeast of Kenya some type of woodlands occur, dominated by Leguminosae: 80% of trees are Julbernardia sp. and Brachystegia sp. Locally co-dominant are Pterocarpus congolensis and Afzelia cuanzensis. Fires are frequent.

Acacia woodlands (A. labai and A. abyssinica) occur in the highlands.

In the more open types of vegetation, the woody component is generally composed of small broadleaved trees, predominantly Combretum spp., often together with Terminalia spp. In drier areas Acacia and Commiphora become more and more prominent (13).

In areas of derived savannas woody communities occur with the genera Parinari, Protea, Erythrina and Rhus among others.

In a broad belt around the Kenya highlands, between 1 200 and 1 500 m and within an annual rainfall range from 500 to 750 mm, the Acacia-Themeda wooded grassland with different Acacia species is the main vegetation type

Pure grasslands, without woody vegetation are confined to some highland areas (12).

Bamboo formations (NHB)

In the intermediate and wetter zone of the uplands, between 1 800 and 3 300 m, the mountain bamboo (Arundinaria alpina) covers large stretches on the Mau and the Aberdare ranges; and it also occurs in scattered patches on the eastern side of Mt. Elgon. In the bamboo thickets, shrubs can be found like those of Mimulopsis.

Coniferous forests (NS)

Patches of a forest type dominated by Ocotea usumbarensis and Podocarpus spp. (mainly P. milanjianus) occur often in the belt between 1 700 and 2 400 m above sea level with a rainfall of about 2 200 mm on the eastern slopes of the Alberdares and of Mt. Kenya. In the drier highland areas, ranging from 1 000 to 2 900 m, with a major development between 1 800 and 2 900 m and an annual rainfall of around 1 100 mm, the Juniperus forest is widely distributed. Juniparus may be accompanied by Olea africana, Podocarpus gracilior, P. milanjianus and Croton megalocarpus. An excessive population of big game damage these forests on the hills and mountains in northern Kenya. On the eastern side of Mt. Elgon, around 2 800 m, Podocarpus trees are widely spaced and growing up to 30 m, with in between a few trees up to 20 m of Olea hochstetteri. Many smaller hardwood trees are also present.

Shrub formations (nH)

Vast areas of the semi-arid eastern and northern parts of the country and of the Rift Valley are covered by so-called bushland and thicket vegetation, characterized by small trees, branching from the base, and often thorny bushes, with a sparse growth of grasses. In the denser forms (thickets) there is no grass cover. Commiphora is the most widespread genus with emergent baobab trees (Adansonia digitata) in places. Communities dominated by Euphorbia are found in very dry sites.

In the most arid parts of northern Kenya large areas of semi-desert vegetation are characterized by widely spread dwarf shrubs and bushes, without any ground cover, except during the short rainy season. Main genera are Acacia and Commiphora.

1.1.2 Present situation of the woody vegetation

Present areas

Areas of natural woody vegetation estimated at end 1980
(in thousand ha)

The following estimates and assumptions were made to arrive at the above figures, based mainly on the documents (4), (11), (13) and (15):

• the same percentage of coniferous forests as given by the FAO World Forest Inventory 1958 (8.8% of the total area of “forests in use” for “pure” coniferous stands and 27% of stands where coniferous trees are dominant were applied to the area of closed forests at end 1980, resulting in an area of 265 000 ha of forests with dominance of conifers, of which 86 000 ha are covered by pure coniferous forest. The assessment of the various categories within the NS and NHC areas has been done proportional to the totals of each category. However, it was assumed that all unproductive coniferous forests are protected by legal status (NSf2i = 0 and NSf2 = NSf2r);

• the huge area of nH corresponds to poor shrub vegetation in the extensive semi-desertic areas of the northern and northeastern zones: according to (13), there exist in these areas “some grazing and subsistance-oriented shifting cultivation”;

• 90% of forests on private land (141 000 ha in 1978 (11)) were considered productive closed forests already logged over (N.f1uc). The remaining 10% are black wattle plantations for tanning industry (see section 1.2);

• no significant deforestation is taking place in the mangroves, which occupy an area of 45 000 ha (13), (4), (11);

• about half of all non-gazetted, non-private forests (121 000 ha in 1974 according to (11)), was considered to be forest fallow (N.a), the other half being classified as closed forests already logged-over (N.f1uc);

• the same percentages of productive forests and protective forests for gazetted forests as given in (4) (respectively 53 and 47%) were applied to the areas estimated at 1980.

Legal status and management

(4) mentions that the following areas were under working plans (W.P.) in 1985:

The area covered by forest reserves with sanctioned and approved W.P. (estimated at 400 000 ha in 1980) has been distributed among NHc/NH01, NHc/NHO2, N.f1 and N.f2, according to their respective areas, resulting in an area of 72 000 ha of managed closed productive forest (N.f1m). The majority of the closed forests is gazetted and falls under the jurisdiction of the Forest Department. However there should remain in 1980 about 110 000 ha of forest in large private farms. The gazetted forest areas are divided in government lands and trust lands, which, according to the information contained in (4), made up 73% of all gazetted forest areas in 1966.

Apart from the gazetted forest reserves there were 2 410 000 ha of national parks in 1975 (13) in which flora and fauna are entirely protected; and 458 000 ha of other types of game areas as national reserves, where apart from protection of wildlife other land uses are permitted; and Country Council game reserves, managed by the local authorities, which might allow also for other land uses. It was roughly estimated that 20% of the area of unproductive woodlands fall under one of the previous mentioned categories.

Forest utilization

Log harvesting

The main commercial species from natural forests are podo (Podocarpus gracilior, P. milanjianus), east african pencil cedar (Juniperus procera), camphor tree (Ocotea spp.) and Elgon olive or oliondo (Olea spp.), but according to (3) they have been cut out largely in the economically accessible reserves. The proportion of timber extracted from plantations is increasing regularly. Around 1930 Juniperus was regarded as almost the commonest timber tree in Kenya (12). However, in 1965 plantations produced already 53% of the total saw and veneer log production in the country (3). According to (7), the total cut in 1968 (135 000 m³) consisted for 22% of cedar and for 16% of podo. Nowadays the cut in plantations occupies a still higher percentage.

According to the “1978 FAO Yearbook of Forest Products” the average annual production of sawlogs and veneer logs was 275 000 m³ and 360 000 m³ for the periods 1971–75 and 1976–78 respectively. Annual coniferous log productions was for the same periods 230 000 m³ and almost 300 000 m³. About 20% of total timber production is for export (11). Softwood exports to East Africa from 1968 to 1970 were for 85% cypress and for 15% podo and cedar (9).

Logging is mainly carried out by private firms with licenses obtained from the Forest Department. Skidding is done by rubber tyred and crawler tractors. In 1976 there were about 180 sawmills operating under long or short term licenses (15). Some logging is done by F.I.T.C. (Government Forest Industrial Training Centre) for private sawmills on a commercial basis (15).

Recovery rate from log to timber is estimated between 40 and 50%. Little is known about output per ha. In (8) for “cutting class 5” (merchantable forest of large size on good sites with trees over 75 cm DBH), a “gross commercial volume per ha” (trees over 30 cm diameter of commercially important species) was found equal to 114 m³/ha. However, this volume is much higher than the volume of extracted logs (VAC) over the whole country, the more so as cutting class 5 is the commercially richest forest. Likely estimates for VAC at the country level are 27 m³ and 30 m³/ha for broadleaved and coniferous forests respectively.

Other forest products

Wood consumption consisted for 95% of fuelwood and poles in 1970 (7). A non-wood forest product is cedar oil, of which exports amounted to 58 tons in 1972, being fairly constant over the years (11). Annual harvesting of bamboo was estimated at 2 900 tons in the FAO World Forest Inventory (1958).

1.1.3 Present situation of the growing stock

The following table gives very tentative estimates of the growing stock.

Growing stock estimated at end 1980
(totals in million m³)

Volumes per ha were based on the 1958 FAO World Forest Inventory, on corresponding figures from Uganda forests, and on (8).

1.2 Plantations

1.2.1 Introduction

Conifers were first tried in plantation in 1902. Large-scale planting started in 1929 when 250 ha were planted. From then on the annual planting rate increased steadily: 350 ha in 1932, 500 ha in 1939. A special development committee recommended in 1946 an intensified plantation programme. An annual planting programme of 2 000 ha started, which rose to 4 000 ha by 1958 and to 5 700 ha by 1960.

Until about 1945, almost all planting was with Cupressus spp. but since then Pinus spp. (P. patula and P. radiata) became increasingly important. Present composition is now 47% Cupressus and 53% Pinus.

The final target of the plantation scheme was established in 1963 at about 120 000 ha, with an annual planting of 4 800 ha. In 1966 a new final target figure was decided which amounted to 142 000 ha of softwood plantations by 1975 (7).

In 1965 planting started for the production of pulpwood. In 1968 annual planting had reached 1 200 ha at Turbo, 30 km east of Broderick Falls. According to (7), the Turbo plantations will start yielding pulpwood by the mid-eighties. 20 000 ha of already established plantations were set aside for the immediate supply of pulpwood to the proposed mill.

1.2.2 Areas of established plantations

Industrial plantations

Areas of established industrial plantations estimated at end 1980
(in thousand ha)

According to (1), the total plantation area was 66 000 ha at end 1959, of which 47 000 ha of “exotic softwoods” (with an annual planting rate to be increased to 5–6 000 ha, to reach a final target of 121 000 ha). The balance of 19 000 ha was consisting of “hardwoods” being planted at a much lower annual rate and including fuelwood plantations (see below). By the end of 1964 the area of plantations amounted to 85 000 ha, according to (2): about 68 000 ha of fast-growing exotic softwoods, 6 500 ha of hardwood plantations and 6 600 ha of fuelwood plantations. (4) gives a plantation area at end 1965 of 89 100 ha: 76 000 ha for softwood plantations, 6 400 for hardwood plantations and 6 700 ha of fuelwood plantations. This figure appears somewhat overestimated when compared to other sources. Plantations with slow growing softwood species (Juniperus procera) were started in the thirties but had been discontinued by 1965 (2).

Since 1965, planting of other softwood species (mainly Pinus patula, P. radiata and Cupressus lusitanica (cypress)) amounts to about 5 000 ha per year (2) for sawtimber. The pulpwood plantation scheme is based exclusively on pines (6).

By end 1967, the area of industrial plantations had grown, according to (4) to 90 000 ha, of which 83 700 ha with softwoods. (9) gives for end 1970 130 000 ha of industrial plantations, and an annual planting rate of 6 000 ha, Pinus spp. and Cupressus spp., corresponding to 45%. After 1970, annual harvesting is estimated at 1 300 ha (15), resulting in a net annual increase of the plantation area of 5 200 ha. In a personal communication a total annual establishment rate is mentioned of about 5500 ha per year (3 300 ha of cypress and 2 200 ha of pines) for the period 1975 to 1978. It is not clear if this establishment rate refers to new planting only or includes replanting of logged-over plantations.

The table shows that hardwood plantations for timber production have been stopped since 1970, the entire timber and pulp plantation programme of Kenya being carried out now with exotic softwood species.

The majority of the industrial plantations is found west of the Rift Valley and in most of the highland regions east of the Rift Valley (15), between 1 800 and 2 700 m a.s.l. Up to 2 100 m P. patula is predominant, and is replaced higher up by P. radiata which has better growth on higher elevations (7). However, plantation of P. radiata has been restricted to absolutely “safe sites” with no danger of Dothistroma pinii attacks. Apart from Cupressus lusitanica, two other cypresses are planted: C. macrocarpa and C. benthamii. The exotic softwood plantations have been established through a kind of taungya system, locally called “shamba” (garden) system.

Other plantations

Plantations for fuelwood and poles are estimated at end 1980 at almost 10 000 ha and approximate age class distribution is indicated in the following table.

Areas of established non-industrial plantations estimated at end 1980
(in thousand ha)

(ind. = indeterminate)

¹ formerly called Acacia decurrens var. mollissima

Previous table is based up to 1969 on (7). Planting during 1966 was 100 ha according to (4) (6) gives a planting of 200 ha for 1967; in 1970, planting amounted to 600 ha (9). Over the period 1971–1980 an annual planting rate of 420 ha has been assumed tentatively. Areas logged over annually can be estimated at 500 ha. (4) mentions for 1966 210 ha.

According to (10) there exist about 14 000 ha of plantations of Acacia mearnsii¹ (black wattle) grown for tanbark (“wattle extract”). These plantations seem to provide also a fuel and charcoal production in the highlands.

All plantations

Areas of established plantations estimated at end 1980
(in thousand ha)

1.2.3 Plantation characteristics

However, these data seem somewhat too homogeneous for the different species. (8) gives the following data for 38-year old plantation of Cupressus lusitanica: total volume over bark: 429 m³ per ha; merchantable volume to 10 cm top diameter, underbark: 397 m³ per ha; merchantable volume to 15 cm top diameter, under bark: 394 m³ per ha. The following table giving volumes per ha in some plantation areas is based on the same document.

2. Present trends

2.1 Natural woody vegetation

2.1.1 Deforestation

Average annual deforestation
(in thousand ha)

Periods:

The table has been built up from the following main indications:

• (6) mentions that during the period 1966–68, 10 000 ha of gazetted productive forests (N.f1m and part of N.f1u) were lost to farming;
• the comparison between progress reports for 1966 (4) and for the period 1966–72 (11) indicates that the gazetted natural high forest is being cleared at the annual rate of 1.9%, with about two thirds of it mainly in managed productive broadleaved forests (NHCf1m) and productive broadleaved forests already logged-over (NHCf1uc); from the above data and other indications found in the literature, present annual deforestation rates have been estimated for the various categories of productive closed forests (N.f1);
• annual deforestation of unproductive closed forests has been estimated at 8 000 ha (6 000 ha in broadleaved forests and 2 000 ha in coniferous forests); comparison between (4) and (11) provides an annual deforestation rate in bamboo stands of 3 000 ha;
• it has been estimated that forest fallow area (N.Ca) increases annually by about 2 000 ha (1 000 ha in broadleaved forests and 1 000 ha in coniferous forests).

One main cause of clearing of closed forests is for the establishment of forest plantations (around 5 000 ha per year in N.f1). Another one is agriculture: for instance, in three years (1966–68), 10 000 ha of gazetted productive forest were lost to farming (6).

Woodlands are subject also to clearing by agriculture. Annual deforestation in woodland areas has been estimated at 20 000 ha. Shifting cultivation exists in communal lands, usually held under trusteeship of local country councils, mainly found in the Coast province and Masailand. It is estimated that within the rangelands of Kenya there are about 740 000 subsistence cultivators occupying some 760 000 ha.

2.1.2 Degradation

In the vast dry areas of northern Kenya where nomadic pastoralism is practised, cattle is the only source of living. Overgrazing is very common, resulting in land degradation and consequent desertification. Other degradation factors are, as in other areas of similar conditions, repeated bush fires, overexploitation for firewood and charcoal and reduced fallows.

2.1.3 Trends in forest utilization

The stimated gross potential cut per year from exotic softwood plantations is estimated for the 1980–84 period between 1 604 000 m³ and 1 732 000 m³ and for the 1985–89 period between 1 732 000 m³ and 1 936 000 m³ (bole volume under bark). Annual sawlog potential cut from the same plantations and for the same periods is estimated between 913 000 m³ and 1 064 000 m³ and between 1 064 000 m³ and 1 355 000 m³ respectively. The output of sawlogs and veneer logs from the natural forests is likely to remain small, of the order of 100 000 m³ or less.

2.1.4 Areas and growing stock at end 1985

Areas of natural woody vegetation estimated at end 1985
(in thousand ha)

Growing stock estimated at end 1985
(in million m³)

2.2 Plantations

Industrial plantations

Areas of established industrial plantations estimated at end 1985
(in thousand ha)

No significant changes of the plantation characteristics are expected. However if a pulp mill is established at Turbo, and its supply become difficult, some of the coniferous plantations, managed on a 30-year rotation basis, might be felled before they reach that age.

Areas of established non-industrial plantations estimated at end 1985
(in thousand ha)

Areas of established plantations estimated at end 1985
(in thousand ha)