TROPICAL AFRICAN CEDARS (WIDDRINGTONIA, CUPRESSACEAE) - SYSTEMATICS, ECOLOGY AND CONSERVATION STATUS

Phenetic analyses of 24 morphological characters, collected in the fie ld for 150 trees of Widdringtonia in Malawi, Zimbabwe, Mozambique and northern South Africa, show two distinct clusters. One can be identifi ed as W. whytei, a tall, wide-crowned forest tree endemic to Mt Mulanj e in Malawi, while the other is W. nodiflora, a multi-stemmed shrub or narrow-crowned tree, which is common on Mulanje and widespread in sou thern Africa. These two sympatric species are distinct on phenetic, ph ylogenetic, ecological and biological grounds. The distinguishing char acters of the two species are analysed and discussed and the differenc es are related to different responses to fire. Widdringtonia whytei is a forest pioneer with limited fire survival ability, while W. nodiflo ra coppices after fire and is common in fire-prone heathlands. To date it has been assumed that there is a single species of Widdringtonia o n Mt Mulanje, and this has led to faulty management and exploitation d ecisions. Extensive plantations of the economically useless W. nodiflo ra have been established, in the belief that they are the economically desirable Mulanje cedar, W. whytei, which is now in danger of extinct ion. (C) 1997 The Linnean Society of London.