Botanical methods in ethnopharmacology and the need for conservation of medicinal plants.

An imperative demand imposed on all scientific investigations is that they should be repeatable, which calls for adequate documentation from the very beginning. In medicinal plant research, botanical documentation plays a vital role since without correctly identified material and properly documented voucher specimens the results are at best suspect and at worst useless. The botanical contributions required for ethnopharmacological research thus include adequate naming of the material and deposition of properly labelled voucher specimens in at least two public herbaria. Ethnopharmacology depends, however, upon botanical assistance also in another respect, viz. concerning conservation. This field may seem to have little to do with ethnopharmacology, but without joint efforts to save the useful plants from extinction, ethnopharmacology will lose important parts of its main source at an appalling rate.