West African Lower Montane Forest

These forests occur in upland areas such as the Nkolmedjabambon, Ongongo and Nkolebengue hills and on Mount Cameroon. They typically occur above an altitude of about 1800 m and have a more open and irregular structure than lowland forests. On Mount Cameroon the more closed areas have two discontinuous tree layers. The highest can reach heights of 40 m or so and comprise just three species: Schefflera abyssinica and the endemic or near endemic Schefflera manni (Araliaceae) and Syzygium staudtii (Myrtaceae). The second storey reaches heights of about 18 m and includes Canthium glabriflorum, Pittosporum mannii, Pygeum africanum, and the endemic Allophylus bullatus (Sapindaceae). Other endemic trees include Afrostyrax lepidophyllus (Huaceae), Dacryodes macrophylla (Burseraceae), Garcinia mannii (Hypericaceae), Leonardoxa africana (Fabaceae), and a variety of regionally endemic species like Anisophyllea polyneura (Anisophylleaceae), Endodesmia calophylloides (Hypericaceae), Fillaeopsis discophora (Fabaceae) and Protomegabarica stapfiana (Euphorbiaceae).  Many of the trees are evergreen but unlike their lowland counterparts they tend to have hemispherical crowns and short gnarled trunks, while plank buttresses are absent. They also lack the cauliflory habitat of lowland species. The two Schefflera species start their life histories, as epiphytes but eventually become stranglers like some Ficus species. The undergrowth is very rich in species but extremely varied in structure. Shrubs can reach heights of 4 m and typically includes Crassocephalus mannii, Discopodium pinninervium, Maesa lanceolata, Solanum mauritianum and the endemic Pavetta hookeriana (Rubiaceae). Also conspicuous are the two giant acantheceous herbs Mimulopsis solmsii and the endemic Oreacanthus mannii (Acanthaceae). In fact, much of the undergrowth is dominated by these two species and few others can tolerate the shade beneath them. In less shady areas, the field layer is characterized by dicotyledonous species especially small members of the Acanthaceae such as the endemic Isoglossum glandulifera (family?), while other endemics include Cyperus mannii (Cyperaceae), Palisota mannii (Commelinaceae) and Senecio burtonii (Asteraceae). There is also an abundance of stinging Urticaceae such as Fleurya ovalifolia and Laportea alatipes, and ferns such as the endemic or near endemic Pteris togoensis (Pteridaceae). Bryophytes are also well represented. Climbing plants, such as the endemic Mikaniopsis maitlandii (Asteraceae), are numerous but not a conspicuous feature of the vegetation. Most are slender twiners or root climbers and the only true liana is Clematis simensis, although certain other species like the endemic Urera cameroonensis (Urticaceae) approach the size of lianas. Epiphytes are very abundant and include flowering plants, ferns, lycopods and bryophytes. Among the flowering plants are Pleopeltis preussii and the endemic Polystachya alpina (Orchidaceae).

Cameroonian Upper Montane Forest

At elevations between 2000-2900 m on Mount Cameroon there are patches of stunted, open forest with trees reaching no more than about 6 m high. The main trees are Hypericum lanceolatum, Myrica arborea and the endemic Agauria salicifolia (Ericaceae), while common shrubs are Adenocarpus mannii and Philippia mannii. A dense sward of tussock grass dominates the field layer with species such as Andropogon distachys and Bromus leptocladus. Also here are various large forbs like the endemic Peucedanum angustisectum (Apiaceae) and Succisa trichotocephala (Dipsacaceae), while smaller forbs include the endemic Wurmbea tenuis (Colchicaceae).

East African Afromontane Forest

Ranging in altitude from about 1700 to 3300 m these forests are extremely varied with many broad-leaved hardwoods and a number of conifer species. Some of the more important trees are Ekebergia rueppelliana, Juniperus procera, Olea chrysophylla, Podocarpus gracilior and Pygmaeum africanum, but on some mountains, such as Mount Kenya, the formation has three distinct zones - a lower montane rainforest, a middle zone where the bamboo Arundinaria alpine often attains dominance, and a higher zone co-dominated by Hagenia abyssinica and Hypericum leucoptychodes. On Kilimanjaro both bamboo and Hagenia-Hypericum zones are lacking. The endemic species found within these montane forests often straddle more than one of the above-mentioned zones. Nevertheless, endemic species such as the grass Anthoxanthum nivale (Poaceae), the sedge Carex conferta (Cyperaceae), the woodrushs Luzula abyssicca and Luzula johnstonii (Juncaceae), and the giant orchid Habenaria eggelingii (Orchidaceae) are more often associated with lower zones, while endemic grasses such as Agrostis gracilifolia, Agrostis sclerophylla, Festuca pilgeri subsp pilgerii (Poaceae), together with herbaceous species like Bartsia kilimandscharica and B. longiflora (Scrophulariaceae), Galium ossirwaense (Rubiaceae), Peucedanum friesiorum (Apiaceae), Satureja simensis (Lamiaceae), Swertia lugardae (Gentianaceae), Valeriana volkensii (Valerianaceae), and shrubs like Helichrysum chionoides and Senecio snowdenii (Asteraceae) are typically associated with the bamboo zone. Endemic species often straddling two or more of these zones include the grass Helictotrichon milanjianum (Poaceae) and forbs like Bartsia macrophylla (Scrophulariaceae), Cerastium afromontanum and Stellaria sennii (Caryophyllaceae) and Crassocephalum ducis-aprutii (Asteraceae).

East African Afromontane Ericaceous Woodland

Between altitudes of about 3000 to 4000 m montane forest gives way to woodland dominated by giant heaths and heath-like plants, especially on the wetter mountains such as Ruwenzori and the Virunga volcanoes. The endemic Philippia trimera (Ericaceae) is often dominant growing to heights of about 13 m. Other associated trees, possibly dominant in some cases, include the endemic Hypericum bequaertii and H. keniense (Hypericaceae), Philippa excelsa and P. johnstonii (Ericaceae), and Senecio erica-rosenii (Asteraceae), while other common plants include the almost arborescent endemic umbillifer Peucedanum kerstenii (Apiaceae). However, in some circumstances there may be very little Philippia or Erica and are largely replaced by the endemic Stoebe kilimandscharica - a member of the Asteraceae with an ericoid habit. The ground layer may include endemic grasses such as Agrostis kilimandscharica, A. leptophylla, A. trachyphylla, A, volkensii, Pentashistis borussica, P. minor, P. ruwenzoriensis [Ruwenzori], Poa schimperana (Poaceae) and various endemic forbs such as Anagallis serpens subsp. meyeri-johnannis (Primulaceae), Anemone thomsonii, Delphinium macrocentron (Ranunculaceae), Bartsia petitiana, Celsia scrophularaefolia, Veronica glandulosa (Scrophulariaceae), Carduus kenensis (Asteraceae), Geranium kilimandscharicum (Geraniaceae), Hypericum afromontanum [Elgon] (Hypericaceae) Lobelia lindblomii (Campanulaceae), Pimpinella kilimandscharica (Apiaceae), Satureja kilimandscharica (Lamiaceae), Trifolium burchellianum var. johnstonii (Fabaceae), and in the marshy areas the orchid Disa stairsii  (Orchidaceae) and sedge Carpha eminii [Ruwenzori] (Cyperaceae), There may also be several endemic megaphytic lobelia herbs such as Lobelia bequaertii [Rumenzori] and L. keniensis (Campanulaceae). Endemic shrubs may include several shrubby alchemillas such as Alchemilla elgonensis, A. roccatii, A. stuhlmannii and A. triphylla (Rosaceae), together with Blaeria folago (Ericaceae), Hypericum kiboense (Hypericaceae), Protea kilimandscharica (Proteaceae), Senecio rhammatophyllus (Asteraceae) and Thesium kilimandscharica (Santalaceae).

East African Afromontane Dendrodsenecio Woodlands

The spectacular woodlands are one of the most unique plant communities in the afro-mountains. The subgenus Dendrosenecio is represented in different mountains by different but closely related endemic species. They normally grow between 4-6 m tall and may form dense forests as on Ruwenzori and the Virunga volcanoes, whereas on Aberdare, Elgon and Mt Kenya they are much more open, and on Kilimanjaro only occur as scattered stands.  The altitude of these forests varies from mountain to mountain - on Ruwenzori they range from 3800 to 4350 m. The main species are Senecio (Dendrosenecio) erici-rosenii and S. adnivalis on Virunga, S. elgonensis and S. barbatipes on Elgon, S. battiscombei and S. brassiformis on Aberdare, S. brassica and S. keniodendron on Mt Kenya, and S. cottonii and S. kilimanjari on Kilimanjaro. Often intermingled with these are various endemic, macrophytic lobelias (Campanulaceae) such as Lobelia lanuriensis, L. telekii and L. wollastonii. These typically grow to heights of between 2 and 4 m, but L. lanuriensis can achieve 7 m.  Typically the scrub layer is dominated by shrubby, endemic alchemillas (Rosaceae) including Alchemilla argyrophylla, A. elgonensis and A. johnstonii - the latter often forming a dense scrub on Virunga.  Of particular interest in the ground layer are the many temperate and boreal elements, some of which like Arabis alpina and Descampsia flexuosa are taxonomically indistinguishable for their counterparts in northern Europe, whereas others like Cerastium octandrum var. adnivales (Caryophyllaceae), Myosotis keniensis (Boraginaceae) and Valeriana kilmandscharica (Valerianaceae) have become distinct endemics. Other endemic ground layer species include Alchemilla microbetula (Rosaceae), Carduus ruwenzoriensis [Ruwenzori], Crassocephalum ducis-aprutii and Senecio polyadenus (Asteraceae). Finally, another interesting feature of this community on Ruwenzori is the endemic climber Galium ruwenzoriense (Rubiaceae), which can climb to heights of 5 m or more on the giant senecios.

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