The study of lianas
Take almost any profile diagram of rain forest and it reveals you the neglect: nothing but trees. Even in Flora Malesiana* the manner of their climbing is not always indicated. Foresters regard them as weeds and persecute them systematically (see FOX 1968), which subjects them to extra dangers beyond the ’normal’ forest devastation. This makes them perhaps the most threatened life form amongst plants. Yet it is good to remember that two of the main climber families, Menispermaceae and Piperaceae, contain an extraordinary variety of interesting chemical substances (see HEGNAUER in the reference list). For this same reason it is risky to drink water from Menispermaceae trunks, as can be done by holding up a fresh-cut piece of 1-1½ m (Piperaceae are slenderer). Rattans, which are largely bound to primary forest, are of course well known, also economically. Horticulturists have taken hundreds of ornamental climbers in cultivation, on which MENNINGER produced a large popular book, with quite a body of practical knowledge. Lianas (i.e. the larger woody vines) occur in a great number of families, although concentrated in about a dozen; taxonomically as well as morphologically they are heterogeneous. They are a main feature of the tropical forests, where according to an old estimate, they make up 8% of the flora, far less so in the temperate forest (about 2% of a much poorer flora). MEIJER (quoted by FOX, 1968) estimated their number for Sabah alone at 150 genera: 13 in the Asclepiadaceae, 12 in the Menispermaceae, 10 in the Rubiaceae, 9 in the Apocynaceae, 9 in the Leguminosae, 8 in the Annonaceae. As for numbers of individuals, in Sabah, FOX (1969) found on ten plots of 0.4 hectares in typical lowland dipterocarp forest an average of 839 climbers (range 472-1146); out of these 690 (range 380-1003) were thinner than 2½ cm, while 56 (range 28-91) were thicker than 5 cm.
|Journal||Flora Malesiana Bulletin|
|Rights||Released under the CC-BY 4.0 ("Attribution") License|
Jacobs, M. (1976). The study of lianas. Flora Malesiana Bulletin, 29(1), 2610–2618.