Have you ever wondered why plants have those Latin names? This is a way for people of the world who speak different languages to have a common way to precisely know they are discussing the same plant, because not all plants have English names or English equivalents of names. A plant can have multiple common names since there is no authority overseeing them. Also one common name can be used for multiple plants. It can be confusing. The Latin names are carefully regulated and help simplify accurate communication since each unique plant has a unique Latin name. Textbook lesson aside, here is a real world example of plants represented on our campus at the University of Maryland-College Park.
The common name redtwig dogwood can represent 3 distinct and different species: Cornus sericea (formerly C. stolonifera) or redosier dogwood, native to much of the northern half of North America, Cornus albaor Tatarian dogwood, native to Siberia, Manchuria and N. Korea, and Cornus sanguinea or bloodtwig dogwood, native to Europe and western Asia. Collectively, these plants are used in ornamental landscapes because their twigs tend to have bright, attention-grabbing colors which are particularly noticeable during the winter months. Redosier dogwood is also frequently used as a moisture-loving rain garden plant. Although each species naturally displays red bark on new growth, hence the name redtwig dogwood, each species also has cultivated varieties with yellow twigs.