You Grow Girl™

Binomial nomenclature is also referred to as the latin or scientific name. Latin was at one time the universal (read: European) language of science. All scientific treatises were written in Latin. If you know your latin roots, looking at scientific names can be fun and can give you a clue for the common name or identifying characteristics of the plant: Toxicodendron diversilobum is poison oak.

The scientific method of naming plants is related to the study of taxonomy. Taxonomy is a systematic way of classifying all living organisms. Based on set theory, taxonomists group plants into divisions, families, genera, and species. The characteristics used to group plants have changed over the years. Flower characteristics, such as the number and placement of petals and male and female sexual organs, stem anatomy and genetic information are now used together to group species taxonomically.

Examples of characteristics that determine which division a plant is in: if the plant has a water and nutrient distribution system (mosses and worts don't); if the plant has seeds (ferns don't); if the plants have flowers (conifers don't). Examples of characteristics that determine which family a plant is in: if genetic information indicates a common ancestor within the family (like people - if we have the same grandmother, we are family); flower petal and male and female sexual organ number and placement. Genera and species are often determined by the size of family characteristics - small petals versus large petals, long stamens versus short ones. Genera often have a wider range of sizes and species are, well, more specifically classified.

What is a Plant Species?

Generally speaking, plants of separate species are unable to interbreed. A species is also a group of plants that can be readily distinguished from other plants based on physical appearance but, because plants are so variable, species can be broken down into subspecies and varieties, because sometimes plants that look different can actually interbreed.

Binomial nomenclature refers to the two part name of each species. The first part of the name is the name of the genus and the second part is a modifier of the genus name that indicates the species. Toxicadendron is a genus name and can be used by itself to indicate a member of the Toxicadendron genus or can be used in combination with diversilobum to indicate the particular species within that genus. Diversilobum is only a modifier and is not informative by itself. There is only one genus called Toxicadendron but the species modifier diversilobum can occur in many genera.