Narrowly defined, plant taxonomy is that aspect of the study of plants having to do with taxa—that is, the naming of plant names (nomenclature) and the determination of the hierarchical relationships used to identify them or understand their relationships (identification and classification). More broadly defined, plant taxonomy includes areas of investigation from a variety of disciplines, including classification, nomenclature, phylogeny reconstruction, and investigation of evolutionary processes. Under this broader definition, the goal of taxonomy is to use comparative data to assess relationships between plants, define taxonomic boundaries between species and other ranks, provide means of identifying and communicating about the organisms, and understanding the patterns (and even the processes) in the evolution of the plants. Seen in this way, plant taxonomy overlaps and grades into the disciplines of plant systematics, phylogenetics, and evolution.

Distinguishing, classifying, and naming plant taxa is basic to any study of nature and...