Plant taxonomy is the science that finds, identifies, describes, classifies, and names plants. Thus making it one of the main branches of taxonomy (the science that finds, describes, classifies, and names living things).
Plant taxonomy is closely allied to plant systematics, and there is no sharp boundary between the two. In practice, "Plant systematics" involves relationships between plants and their evolution, especially at the higher levels, whereas "plant taxonomy" deals with the actual handling of plant specimens. The precise relationship between taxonomy and systematics, however, has changed along with the goals and methods employed.
Identification, classification and description of plants
Three goals of plant taxonomy are the identification, classification and description of plants. The distinction between these three goals is important and often overlooked.
1.Plant identification is the determination of the identity of an unknown plant by comparison with previously collected specimens or with the aid of books or identification manuals. The process of identification connects the specimen with a published name. Once a plant specimen has been identified, its name and properties are known.
2.Plant classification is the placing of known plants into groups or categories to show some relationship. Scientific classification follows a system of rules that standardizes the results, and groups successive categories into a hierarchy. For example, the family to which the lilies belong is classified as follows:
- Kingdom: Plantae
- Division: Magnoliophyta
- Class: Liliopsida
- Subclass: ......
- Series(Order): Liliales
- Family: Liliaceae
- Genus: Pine, Wattles, Milkvetch, Dandelion, etc.
- Species: Common water Hyacinth, Yellow star-thistle, Purple loosestrife, Kudzu, etc.
- Variety: ......
The classification of plants results in an organized system for the naming and cataloging of future specimens, and ideally reflects scientific ideas about inter-relationships between plants. The set of rules and recommendations for formal botanical nomenclature, including plants, is governed by the International Code of Nomenclature for algae, fungi, and plants abbreviated as ICN.
3.Plant description is a formal description of a newly discovered species, usually in the form of a scientific paper using ICN guidelines. The names of these plants are then registered on the International Plant Names Index along with all other validly published names.
- APG system (angiosperm phylogeny group)
- APG II system (angiosperm phylogeny group II)
- APG III system (angiosperm phylogeny group III)
- APG IV system (angiosperm phylogeny group IV)
- Bessey system (a system of plant taxonomy)
- Cronquist system (taxonomic classification of flowering plants)
- Melchior system