Afroalpine 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).

Afroalpine Carex Bog

In the lower, more level parts of the afroalpine belt where drainage is impeded there are bogs dominated by endemic, tussock-forming sedges.  The main dominants are either Carex monostachya or C. runssoroensis (Cyperaceae), but the habitat is given a strange appearance by the presence of endemic giant lobelias (Campanulaceae). As the main sub-dominants these include Lobelia bequaertii on Ruwenzori, L. elgonensis on Elgon, L. sattimae of Aberdare and L. deckenii on Kilimanjaro. Other endemic plants may include Kenichloa chionogeiton (Poaceae), Luzula abyssinica, L. johnstonii (Juncaceae), Ranunculus stagnalis, R. volkensii (Ranunculaceae), Romulea keniensis (Iridaceae), Sagina afroalpina (Caryophyllaceae), Senecio transmarinus (Asteraceae) and Subularia monticola (Brassicaceae).  The lower layers, however, are mainly dominated by sphagna and other bryophytes including endemic species such as Meesia kenyae and Scapania hedbergii on Mt Kenya, and Sematophyllum elgonense on Elgon.  

References

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