People from different countries or backgrounds use different common names for the same plant and, in addition, a single common name can refer to more than one plant species.
The confusion that surrounds common names means that the use of scientific Latin names is the preferred convention. Each published Latin name is attached to a 'type specimen', a herbarium specimen, that epitomises the characteristics of that species. No such definitive reference exists for common names.
However, even using Latin names poses challenges. There are around 380,000 species of vascular plants, but over a million scientific Latin names for these at species level. These multiple names (synonyms) arise because plant species can be described and named by different people at different times and different places. Scientific Latin names also change when botanists re-evaluate a plant's evolutionary relationships and place it in a different genus. The problem of synonymy is particularly pronounced for plants widely used by humans, which tend to have more Latin names ascribed to them.
A recent survey of some common medicinal plants by Kew's Medicinal Plant Name Services project (MPNS) suggests that, on average, medicinal plants considered by that project have eight scientific Latin synonyms. This causes problems if we wish to gather all the information about a particular medicinal plant.
A list providing the accepted scientific Latin name for a plant species and linking it to all of its Latin synonyms is an invaluable tool for pulling information together from a variety of disparate sources. One of the major impacts of such a widely accessible list is that it provides a source of species information and nomenclatural data for other information systems. The list also may be used as a tool in its own right for checking the status of a plant name.
Kew, in association with Missouri Botanical Garden, and several other collaborators, has just released a new version of The Plant List, a working list of known plant species. Version 1.0 was produced in December 2010 as a response to the Global Strategy for Plant Conservation (GSPC), adopted in 2002 by the 193 governments who are parties to the Convention on Biological Diversity.