What’s in a name – how plants are named.

Plants (and animals) have always been given names. From the earliest times, names would have described distinctive features of the plant. Names would have been given by, understood, and made sense within a local family group, clan or tribe. Such a system of local or common names would have worked well - until people travelled to new places or started using communication technologies that brought them into contact with strangers who spoke a different language. Over recent centuries printing presses, photography and the internet have all worked to require a standard approach to naming all manner of things, plants included.

When it comes to giving names to living things there are two kinds of names, the formal, or Latin name, and common names. Each has its advantages and disadvantages.

Common names are easier to pronounce and remember as they are usually in our own language. They can also be descriptive eg Golden Wattle, Red Gum, Saltbush, Kangaroo Grass. A problem is that the same common name can be used for different species eg Red Gum could refer to Eucalyptus blakleyi, Eucalyptus camaldulensis or Eucalyptus terreticornis. Common names also vary across localities – a tree called stringybark, or ironbark or mulga in Victoria might be totally different from something of the same name in Queensland. And some plants have many common names. Attempts have been made to standardise common names, but there is no universally agreed system. Nor do common names have any classification system to underpin them, a real problem when it comes to remembering the names.

It is that standardisation and classification that is the strength of the system of Latin or scientific names.

The Latin name emerges from a process whereby plants, when newly discovered are carefully examined and formally described, including how they differ from similar looking ones that have already been described and named. This process enables a name to be given to the plant that shows how the plant is related to other plants with similar features.

The Latin name is a formal scientific name that is recognised, accepted and used worldwide for any species of plant or animal. The convention relies on a two-word or binary name, consisting of a Genus name referring to a group of plants sharing similar characteristics, and a Species names referring to the specific sub-groups of the Genus. This system is called binomial nomenclature (often shortened to just "binomial"), or a scientific or Latin name. Each of the two words making up the binomial uses Latin grammatical forms, although they can be based on words from other languages as well. The first part of the name identifies the Genus to which the plant belongs and the second part, the Species or specific epithet, identifies the Species within that Genus. For example, all humans belong to the Genus Homo (meaning man). Modern humans ( ie us) are given a Species name of “sapiens” (meaning wise) to distinguish us from other, now extinct, species of humans. So the Latin or binomial name for modern humans is Homo sapiens.

This binomial naming system has been in use now for about 250 years. It was originally developed by the Swedish botanist Carl von Linné. His systematic approach to naming plants (and animals) is the universally-recognized system used today. While many wildflower enthusiasts and plant growers struggle with the Latin names of plants, knowing a plant's botanical name allows us to communicate accurately with like-minded people all over the world, an essential capacity as internet and social media expand our communication horizons.

The Latin or Latinised words used to make the binomial often describe features of the plant eg Acacia armata means “prickly wattle”, Banksia coccinea means “red banksia”, “Eucalyptus” means “well covered” referring to the way the bud cap covers the stamens of the flower. ”. Eremophila means “desert loving ”and Eremophila glabra means “smooth eremophila”. These all draw on the Latin words describing these characteristics.

Some plants are named after people. The genus Banksia was named for Sir Joseph Banks who accompanied Cook when he discovered Australia. Lesser mortals have to be satisfied with having just a single species named for them eg Acacia grasbyi commemorates W.C. Grasby who was a teacher.

Just a few more things about the binomial system. The genus name is always written with a capital letter, while the species name is always written with a lower case letter, even if it refers to the name of a person. In printed text binomials are usually written in italics, and if the name is handwritten the words are underlined – although these conventions are now less rigorously adhered to. Following the Latin name there are often some other letters e.g. Benth. or R.Br. These letters are the authority and refer to the scientist who first described that plant, and sometimes a date of publication as well. Eg Golden Wattle, Acacia pycnantha Benth. is our national floral emblem. Its specific epithet pycnantha is derived from the Greek words pyknos (dense) and anthos (flowers), a reference to the dense cluster of flowers that make up the globular flowerheads, and it was first formally described by botanist George Bentham.

I mentioned earlier that the process of describing and naming a plant allows us to show how any species of plant is related to other plants with similar features. There are a number of higher level groupings that bring together plants with similar features. All of the green plants are grouped into the Plant Kingdom, which is broken up into progressively smaller groups: Division, Class, Order, Family, Genus, Species. While the larger groups are too large to have much practical use for laymen, the grouping at Family level is very useful when it comes to trying to identify or recognise plants.

All plants in a given Family will have a lot of characteristics in common. Eg all plants that look like a daisy are in the daisy Family (Asteraceae), and all plants with the characteristics of orchids are in the orchid family (Orchidaceae). Each Family is assigned a “type plant” that shows the particular characteristics that separate this group of plants from other Families. The Family is usually named after this “type plant” although it often won’t be an Australian plant. Grevilleas, Banksias and Waratahs all belong in the Proteaceae Family named after the South African Protea. Eucalypts, Callistemons and Melaleucas all belong in the Myrtle or Myrtaceae Family. It’s easy to recognise a family name because they always end in “…aceae”.

Learning to recognise family characteristics provides a big shortcut when it comes to working out a name for a plant. Features like the arrangement of leaves along the stem, the number of petals and stamens, and how the individual flowers are arranged on the plant will be pretty much constant throughout the family. Matching an unknown plant to a family by matching a few key features is a good first step in finding a name. Many publications arrange plants in Families so it is possible to select a likely family and thus eliminate the need to trawl through pages of unrelated plants. With the right family selected finding a genus and species name often (but not always) becomes quicker and easier.

One word of warning though – the number of plant families varies according to different systems of classification. And as new research is done big families may be split up, or smaller families combined. However even if Family names change, the binomial or Latin name is usually unchanged. Like any area of science new discoveries are being made all the time, and changes to names and how plants are classified are inevitable, even if it is frustrating having to relearn names of familiar plants.