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E.S. Fernando: Vegetatior of the Philippine Islands 11
The lower montane (pine) and upper montane (mossy) forests also continue to be threatened
by milling and by farming of exotic vegetables, especially on Luzon. These formations, when
disturbed and abandoned, are of tell quickly transformed into grasslands.
Ail the natural vegetation of the Philippines is, therefore, endangered and its degradation
continues. The destruction of the natural vegetation and of habitats either by logging, shifting
cultivation or conversion to other uses, is the most serious threat to Philippine biological
diversity. Over-exploitation of particular plant groups is another. Both are real problems that
put the future of the rich and diverse Philippine flowering plants at stake.
Endangered Plants
Some listings on endangered Philippine plants have appeared in the past (e-g. Quisumbing
1967; Madulid 1982; Tan et al. 1986). The Conventicn on International Trade in Endangered
Species of Wild Fauna and Flora (CITES 1976) has earlier included seven species of Philippine
flowering plants in its appendices, and more are currently being added.
The present state of our knowledge of the Philippine flowering plants is not such that a
thorough analysis can be made of how many and what species are extinct, endangered or
threatened. Many plant groups are still poorly known. We still do not know what plants occur
on what island and in what sorts of habitats. With the extensive devastation of the natural
vegetation and habitats, some species previously occurring in certain areas are, almost
certainly, now either rare or completely absent. The situation is even more serious for endemic
species that are extremely restricted in their geographical range to one or a few localities.
Thus, previous listings of endangered plants are generally incomplete and often conservative in
their estimates.
However, there are a number of species that have been identified as immediately endangered.
Two of these are RaMesia manillana (Rafflesiaceae) and Tectona philippinensis
(Verbenaceae), of Asiatic affinity. Both species are endemic. Rafflesia manillana, although
known from three islands including Luzon, has never been recollected. The small population on
Mt Makiling (one of only two sites on Luzon) is probably nearly extinct, and was last seen in
1982 just before the site was bulldozed for geothermal exploration. Tectona philippinensis
occurs only in a small area near Lobo in Batangas Province in southern Luzon and on lling
Island off southern Mindoro. The small area on Luzon where this tree grows has been
converted into an exotic fruit tree plantation and the remaining individual trees are felled for
charcoal production.
A great number of species are also very rare occurring only in particular habitats and localities.
For example, in the large genus Medinilla (Melastomataceae) many of the Philip~ine endemics
are very local in their distribution (Regalado 1989). In the Palmae about a dozen endemic
species are known only from one or two adjacent localities (Fernando 1990) and some have no
longer been sighted in their known areas in recent visits and are now believed to be extinct.
These examples illustrate the situation for many endemic species of Philippine flowering plants.