Identification of tropical woody plants in the absence of flowers and fruits

While studies of forest vegetation may differ in their underlying objective, be it physiology, ecology or biodiversity, common to all these is the fact that all require taxonomic knowledge. The process of taxon- omy or of forest ecology begins in principle with an inventory of the flora, the evaluation of this inven- tory still being based to a large extent of reproduction-related organs. In a tropical forest, the majority of flowers or fruits are most often found in the canopy. The canopy, however, is difficult to reach and to do so necessitates heavy, expensive or sophisticated equipment such as a tower, a crane, or a hanging platform suspended from a dirigible balloon. Thus, most of the time, botany is practised near the ground with the aid of light equipment such as ladders, branch- loppers, and climbing irons. Furthermore, a large proportion of the trees and lianas of the understorey bear neither flowers nor fruits at certain times of the year. Despite this absence of seasonal characters it should at least be possible to recognize the families of plants by means of easily observable and permanent characters. To meet this need, an identification system has been designed in the form of a dichotomous key. In addition to permitting recognition ofplantfamities in the field in all seasons, this system can serve as a starting-point for a more detailed knowledge of the forest taxa.