he ultimate challenge for any climber in Africa must surely Tbe to reach the summit of the highest mountain in Africa, and one of the world's highest free standing mountains, Mount Kilimanjaro (affectionately known as 'Kili'). Situated three degrees and some 330 km south of the equator in northern Tanzania, Mount Kilimanjaro, with it's highest point, Uhuru Peak, measured at 5895 m (19 340 ft) above sea level, holds a unique place in both the Western and African psyche. The mountain has featured in stories, films and even popular songs, including 'Africa' by the group Toto, and 'Kilimanjaro' by Juluka. I had the opportunity, in February this year, to climb Africa's highest mountain Above. Kilimanjaro's glaciers. The Furtwangler Glacier (ca 5750 m) in the centre and the via the less popular, albeit more large Northern Icefield can be seen on the horizon. scenic, Machame Route (also known Facing page. Fire and ice. Sunset on Kibo, Mount Kilimanjaro. Photos: C.K. Willis. as the 'Whiskey' Route, as opposed to the more popular Marangu or corridors or rights of way through of the mountain, and snow falls at 'Coca-Cola' Route), a total distance the Kilimanjaro Forest Reserve the top of the mountain. The shorter of about 80 km, with an altitudinal which was established in 1921. In rainy period is from October to range of about 9500 m. To put the recognition of its beauty, cultural December. January and February are height of the mountain into and spiritual significance and size, usually dry, warm and clear with perspective, southern Africa's Mount Kilimanjaro was declared a brief rainshowers which make good highest point, Lesotho's, Thabana World Heritage Site in 1989. Mount climbing conditions. Ntlenyana, is a mere 3482 m. Kilimanjaro is composed of three Ninety six percent of the water Walking seven to eight hours per extinct volcanoes: Kibo (considered on Kilimanjaro originates in the day, single file on a well-worn path by some to be dormant, rather than forest zone, where it percolates as part of a group of eleven climbers extinct) at 5895 m in the centre, through the soil to emerge as does not allow much spare time for Mawenzi at 5149 m (16 893 ft) in springs lower down the mountain. botanizing. On days four and five, the eaft; and Shira at 3962 m Kilimanjaro's forests receive about we reached the summit of (13 000 ft) in the west. The three 2000 mm rainfall per annum on the Kilimanjaro and descended the peaks repr~s'ent three g~nerations of southern slopes, with the same same day, walking for twenty-three volcanic activity, Shira the oldest . forests receiving about 1000 mm on . hours, with two hours sleep and (and most eroded), and Kibo the the northern and western slopes. covering an altitudinal range of youngest. Whereas the older two Above 1500 m the rainfall decreases 4740 m (from Barranco Camp at have been largely destroyed by with altitude so that the alpine zone 3950 m via Barafu (4600 m) to the erosi.on, Kibo is a perfectly shaped receives between 250 and 125 mm, summit at 5895 m and back down to cone with a caldera, about 2 km resulting in an alpine desert in the Mweka Camp at 3100 m)! wide, in the centre of which is a upper reaches of the mountain. Despite its popularity small secondary eruption cone with At the summit, most of the (18 000 visitors each year which is its own crater. The majestic precipitation falls as snow, rather more than 300 per week), very little mountain, which ceased growing than as rain. popular literature is available on the 450 000 years ago, rises 4800 m flora of Mount Kilimanjaro and above the surrounding plains which Botanical exploration information remains scattered in average around 1000 m above sea Several plant collections were inaccessible scientific journals or level. The longest axes of Mount made on Mount Kilimanjaro regional field guides. It is hoped Kilimanjaro, running north-east to between 1861 and the early 1900s, that this account of the flora of south-west, are about 60 km long the most notable being those of Kili,manjaro will serve as useful and 40 km across. Von der Decken, Johnston, Meyer background information for anyone and Volkens. Many of the plants interested in plants and attempting Climate collected during the late 1800s on Kilimanjaro in the future. Mount Kilimanjaro is regarded as the mountain were described in the driest of the tall East African Europe by Engler, and named after Kilimanjaro National Park and the mountains. Unlike Mount Kenya the individuals who collected 'Three Peaks' and the Ruwenzoris, both of which them. * Many plants, as could be A large})Qrtion of the mountain, the have several small lakes or tarns, expected, have the species name 756 km area above the 2700 m Kilimanjaro has only one permanent 'kilimandscharica' or 'kilimanjari', contour, is conserved within the tarn, located close to Mawenzi. Kilimanjaro National Park, managed Rainfall varies both with aspect and Kilimanjaro's vegetation by Tanzania National Parks. The altitude. Most rain falls between Mount Kilimanjaro has a rich and park was established in 1973 and March and June, and it is during diverse flora which includes over officially opened in 1977. It has six this period that rains fall at the base 1800 species of flowering plants
Veld &' Flora December 2000 163 within 163 families and 760 genera, which was flowering prolifically and an unusually high species during our visit was Impatiens diversity among lower plants of kilimanjari subsp. kilimanjari with approximately 720 species of its brilliant red and yellow flowers bryophytes (596 known species) shining in the forest undergrowth. and lichens (120 species). An endemic 1. kilimanjari subsp. Five vegetation belts can be pocsii was described by Christopher recognized. Olov Hedberg, the Grey-Wilson from the upper renowned Swedish botanist who montane forest on the northern side described the vegetation belts of the of Mt Kilimanjaro as recently as East African mountains in 1951, 1997. The pink-flowered Impatiens defined a vegetation belt as an pseudoviola may also be seen here. 'altitudinal region' which can be Other shrubs and herbs include traced on all (or most) mountains of Mimulopsis kilimandscharica and sufficient height in a definite part Solanecio mannii. The forest zone of the world, as for instance the includes many lichens (Usnea), montane forest belt on the East mosses and ferns like Asplenium African mountains. Although actiniopteroides, A. volkensii and Hedberg only recognized three tree ferns, Cyathea (see photo on vegetation belts on Kilimanjaro p. 166). A unique community of (montane forest, ericaceous belt and bryophytes is known to develop on the alpine belt), Mwasaga in 1991 the stems of the tree fern Cyathea included two additional vegetation manniana. The giant Lobelia belts, namely the woodland and giberroa grows as scattered bushland belt, and the cultivated individuals along streams and moist belt. depressions in the montane forest The upper limit of the woodland zone from 1550 m to 3000 m. Above. The endemic Impatiens and bushland belt ranges between kiJjmanjari subsp. kiJjmanjari 900 m (southern slopes) and 1500 m (Balsaminaceae) growing in the montane (northern slopes). It is characterized forest belt on the southern slopes of Kilimanjaro. by a mosaic of Acacia bushland and CombretumlTerminalia woodland. The cultivated belt more or less encircles the mountain and reaches its highest point on the southern slope (1900 m), but in most areas extends no higher than 1700 m. Below. Carduus keniensis, a member of Crops cultivated il;l this zone . the Asteraceae family, growing in the include coffee, bananas, maize, 'r ericaceous belt on Kilimanjaro. This beans, millet, potatoes, cabbage, species belongs to the same genus as the carrots, beets, onions and tomatoes. common European thistles. The lower boundary of the montane forest belt is approxi mately 1700 m on the southern side and 2200 m on the northern side. The upper boundary reaches nearly 3000 m along the southern side and 2800 m on the western and northern sides. Trees characteristic of this belt include Xymalos monospora, Tabernaemontana ventricosa, Macaranga capensis var. kilimand scharica, Myrica saJicifolia, Maytenus undata, Prunus afdcana, Bernard Verdcourt of the Royal Botanic East African pencil cedar Juniperus Gardens, Kew, apparently first came across procera and the East African Helichrysum meyeri-johannis on reaching redwood Hagenia abyssinica. Other the top of Mount Kilimanjaro in the early 1970s. The story goes that the porters tree species, several of which are 'presented members of his team with bright also known from southern Africa, garlands made from the capitula of this include Ilex mitis, Podocarpus plant woven into a wreath of stems from a milanjianus, Ocatea usambarensis, species ofLycopodium'. Verdcourt's Olea africana , Nuxia congesta, 'wreath' can still be found amongst the collections in the Sir Joseph Banks Museum Agauria salicifolia, the Cape for Economic Botany at Kew. This species, Chestnut Calodendrum capense and named after Hans Meyer, is common in Hypericum revolutum. The montane damp to dryish alpine grassland between forest belt receives about 2000 mm 2600 and 4250 m. Flowering at almost any time of the year, it has also been recorded of rainfall per annum on the on Mount Elgon, Cherangani Hills and southern slopes, and contains Mount Kenya. Drawing by Helen Haywood several endemic plants. One species (from Curtis's Botanical Magazine 12(1), February 1995).
164 Veld &- Flora December 2000 The forest zone on Kilimanjaro is recorded flowering plant on Kilimanjaro's giant senecios and less differentiated than on other Kilimanjaro has been Helichrysum lobelias. East African mountains and newii at 5670 m in Kibo's crater, An interesting process is contains neither a bamboo demonstrating an ability to survive associated with the alpine belt. (Arundinaria alpina) nor Hagenia in highly adverse environments. As a result of the nightly freezing Hypericum zone. On most other Only about fifty-five species of and the daily thawing of the upper East African mountains, such as higher plants have been recorded layer of the soil, ice crystals that Mount Kenya (see Burrows & above 4000 m on Kilimanjaro, form in the soil at night loosen and Burrows in Veld Er Flora 80(2), compared with many hundreds in move the topsoil of the alpine semi 1994), Mt Elgon and Mt Ruwenzori, the lower zones. Important genera desert and desert. This form of there is a bamboo forest zone include Senecio, Lobelia, the sclero 'solifluction' can be tolerated only between 2200 and 3200 m. On phyllous shrubs Aichemilla and the by organisms that lie loosely on the Kilimanjaro a few very small everlastings Helichrysum, ground and that can easily change patches are reported to exist only on acaulescent (absence of an above their position. Some mosses the northern and north-western ground stem) rosette plants of the (Grimmia) change their position slopes. It has been estimated that genera Haplocarpha, Haplos daily as the soil surface moves, and 69% of the flowering plant species ciadium and Dianthoseris, as well as a result, ball-shaped colonies found above the cultivated zone on as grass tussocks of the genera develop with shoot apices in all Mount Kilimanjaro are restricted to Festuca, Agrastis, Koeleria and directions. Such 'moss balls' have the montane forest. This figure is Pentaschistis. In its lowest part up been described in other arctic and even higher for the bird (78%) and to about 4300 m, a Helichrysum desert areas of the world. larger mammal species (80%). community dominates, composed The ericaceous belt extends from mainly of Helichrysum newii and Mosses, liverworts and ferns the upper limit of the forest zone, at other Helichrysum species. Another Of the 596 known bryophyte about 3000 m, to an elevation of important shrub of this belt is the species, 415 are mosses and 181 -¥lllfSlximate.1v MlfULm. IhB.e.rir.a yellow-flowered EUJ.yqDs dacz;v 1ipecies are liverworts. Twelve ceous belt of Kilimanjaro contains dioides. This belt is also home to species of bryophytes are strict two zones, the moorland zone and the ericaceous-shrub zone. The moorland zone (between 2800 and 3250 - 3400 m) consists of tussock grassland with scattered low trees or shrubs of Erica excelsa and Erica arborea, together with Artemisia afra, Stoebe kilimandscharica, Helichrysum newii, Helichrysum meyeri-johannis (see accompanying painting) and the conspicuous spiny rosette plant Carduus keniensis also found on Mount Elgon, the Aberdares and Mount Kenya. The dominant shrubs of the ericaceous-shrub zone are the same species as found in the moorland zone, intermingled with Pratea caffra subsp. kilimandscharica (the Above. One of the few flowering plants observed above 4600 m. This member of the commonest Protea species on the Asteraceae was observed flowering at ca 4800 m, between Barafu Camp and Stella Point mountain), Adenocarpus mannii, on Kibo. Anthospermum usambarense and, Below. A stark section of the alpine belt on Kilimanjaro. Photos: C.K. Willis. in boggy areas and along streams, the sedge Carex monostachya (Cyperaceae), Senecio johnstonii subsp. johnstonii var. cottonii and S. johnstonii subsp. johnstonii var. kilimanjari. This zone extends from the upper limit of the moorland zone at about 3250 m up to 3900 m or 4000 m. It is generally accepted that the present appearance of the ericaceous belt has largely been attributed to fire, caused by man. As a result of frequent fires along the upper regions of the montane forest, the ericaceous belt has replaced the montane forest in many areas. The alpine belt extends from the top of the ericaceous belt at about 4100 m to the upper altitudinal limit of plant growth. The highest
Veld Er Flora December 2000 endemics to Mount Kilimanjaro and montane forests as scattered bryophyte flora of Mount represent 2% of the total bryoflora. individuals between 1550 and Kilimanjaro, has observed about In terms of Afroalpine endemics, 3000 m. The rhizomatous forty epiphytic species on the giant though, there are eighty-three 1. deckenii subsp. deckenii occupies Senecio trunks. Chloroplast DNA so species of Afroalpine endemic moist sites in the ericaceous and far examined suggests that the giant mosses and twenty species of alpine zones (3000-4000 m) whilst senecios at high altitude originated Afroalpine endemic liverworts. 1. deckenii subsp. incipiens grows on Mt Kilimanjaro, with subsequent The lower plants serve an important in the upper montane forest zone dispersion to the adjacent Mt Meru, function in terms of regulating the (2700-3150 m). Senecio johnstonii north to the Kenyan mountains water flow and reducing the loss of subsp. johnstonii var. johnstonii (Aberdares, Mt Kenya, Cherangani water through evaporation on grows in the upper portion of the Hills and Mt Elgon), west to the Mount Kilimanjaro. Work on the montane forest zone as a many Ruwenzori Mountains, and then ferns of Mount Kilimanjaro has branched tree up to 8-10 m tall, and south to the Virunga Mountains and revealed that there are over 130 smaller individuals are found in the Mount Kahuzi. This dispersion and species of ferns and fern allies on lower part of the ericaceous belt subsequent speciation all occurred the mountain, with the highest (2500-3100 m). The other two in the past million years. richness recorded in the montane varieties of giant Senecio tend to Convergent evolution has forest belt on the southern slopes, have thicker stems, fewer branches, resulted in similar giant stem rosette especially between 2000 and and persistent dead leaves plants evolving independently in 2300 m. The abundance of ferns (marcescent leaves) surround the the richest high-mountain flora of decreases abruptly above 2900 m thicker stems or branches. the world, the 'paramo' vegetation, and below 1100 m. The highest fern S. johnstonii subsp. johnstonii var. which is restricted to the northern on Kilimanjaro is Cystopteris kilimanjari spans the ericaceous belt Andes of South America and jragiJis (recorded by Hedberg at (3000-3800 m), whereas Senecio adjacent southern Central America. 4750 m), the highest pteridophyte of johnstonii subsp. johnstonii var. Members of the genus Espeletia Africa and probably the hardiest of cottonii grows in the alpine zone (Asteraceae), the jrailej6n (literally, alpine ferns. (3700-4500 m). The most 'big friar' - so called because of the spectacular and largest population greyish woolly coat of pubescence) Africa's giants of giant groundsels I observed on are the classical example, very The plants for which Kilimanjaro is the Machame Route was in the similar to the giant groundsels of most famous are the giant senecios Barranco Valley, where Senecio eastern equatorial Africa. or groundsels (previously classified johnstonii subsp. johnstonii var. in the genus Dendrosenecio), cottonii grew alongside 1. deckenii Vegetation classification Senecio johnstonii subsp. johnstonii subsp. deckenii. Research on the Much has been written about the var. johnstonii, Senecio johnstonii giant groundsels has revealed that zonation of the vegetation on subsp. johnstonii var. cottonii and the average annual stem elongation Africa's tropical mountains, as well S. johnstonii subsp. johnstonii var. rate is about 2.5 em. Specimens can as the links between the 'Cape' kilimanjari, and the giant lobelias, attain height~ of 10 m: the tallest Flora, the Afromontane Region and Lobelia giberroa, 1. deckenii subsp. specimens are abcfut 250 years' old. the flora associateq. with the deckenii (see cover) and 1. deckenii (The weakly expressed subsp. incipiens. As a rule the giant seasons in the tropical senecios and giant lobelias grow in alpine zone mean that moist, open sites and possess an annual rings or other apical rosette of leaves. rhythmical anatomical Lobelia giberroa is certainly the features ca~not be most Widespread of the giants, used for age determi occurring from northern Ethiopia to nation in these the Viphya Mountains in northern plants.) Tamas P6cs, Malawi. It generally grows in a researcher on the
Above. Giant senecios or groundsels, Senecio johnstonii subsp. johnstonii var. cottonii on Kilimanjaro, likened by Otto Kersten to 'dancing spectres'. Taken from a translation of Otto Kersten's account of his journey up Kilimanjaro with Baron von der Decken in 1862. (Originally published in German in the 1870s. The translation was published in 1965 in Tanganyika Notes and Records 64.) Left A grove of tree ferns in the montane forest belt on the Mweke Route, southern slopes. Photo: C.K. Willis.
Veld &- Flora December 2000 The giant senecio or groundsel, Senecio johnstonii subsp. johnstonii var. cottonii in the Barranco Valley, Kilimanjaro, at an altitude of about 3900 m. Photo: C.K. Willis. Afroalpine or Alpine belt. The use relation to temperate vegetation in Gland, Switzerland and Cambridge. of different terminologies by a range other areas of the African continent. Reader, J. 1982. Kilimanjaro. Elm Tree, London. of scientists can easily be confusing Mount Kilimanjaro, like all high to someone trying to make sense of mountains around the world, has *A list of early Kilimanjaro plant hunters the various floras and publications many moods, and although it might and some of the plant taxa commemorating them is available on request from the concerning Africa's temperate flora. not be the most diverse of Africa's Publications Manager at the Botanical Considering the similarities and high mountains in terms of plant Society, Private Bag X10, Claremont, 7735. differences between the various diversity, it does nevertheless Tel (021) 797 2090, fax (021) 7972376, montane floras in sub-Saharan dis~lay very clearly the distinctive e-mail
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