There was a time when plant names were long-winded descriptions of a plant’s most notable features or vernacular monikers which might have only been recognized in a small geographic area. Some native plants have, as a result, a remarkable number of names by which they could be known. Arum maculatum or lords and ladies has, according to Richard Mabey in Flora Britannica, another nine common names including ‘Parson in the pulpit’ and ‘Willy lily’. Even over five hundred years ago, when discussing and writing about plants was limited generally to a select few, these methods must have been incredibly tiresome and not at all foolproof ways of identifying plants. Casper Bauhin (1560-1624) was one of the first scientists to devise a more structured way of identifying plants by giving them two names, but it wasn’t until the 18th century that Carl Linnaeus took the idea and ran with it. He set about the task of classifying all living creatures, now known as taxonomy, and giving them a genus and a species name in Latin, a bit like our surname and Christian name.
There’s no doubt his system has been incredibly useful. If we just relied on common names confusion would be widespread. For instance, in Scotland a plane tree refers to the sycamore or Acer pseudoplatanus, in England the plane tree generally means the London plane tree or Platanus x acerfoila but in North America their own native plane tree Platanus occidentalis is commonly known as the plane or sycamore. And, grouping plants together based on shared characteristics has many benefits, from knowing the sort of habitats plants might share to similar chemical compounds which could be useful when creating medicines.
Latin was always the language of science, universally recognised and accepted, and this has allowed scientists, botanists and horticulturalists to share knowledge and plants without the encumbrances of language barriers. However the system is by no means perfect. Whilst Latin may have been embraced by scientists us gardeners haven’t been quite so enthusiastic. So many of us are put off by Latin names as if they hold some mystical quality about them that means the Latin is only for academics. If you do use the Latin there’s always a worry you’ll sound pretentious or you simply won’t be able to get your tongue around the words. I still can’t pronounce the grass anemanthele (pheasant’s tail grass) without sounding as if I’m trying to teach it to a five-year-old by breaking it down into syllables. And then, just when you think you have mastered the names of the plants in your garden, groups of botanists go and change them to something else. The subject of name changes came up last week with Christina over at My Hesperides and she suggested we should both write posts on the subject.
The ‘Rule of Priority’ is one reason for name changes. Hostas were first named as such in 1812 after the Austrian botanist Nicholas Host but five years later they were renamed funkia after Heinrich Funk. Right through Victorian Britain they were known as funkias, but in 1905 under the ‘rule of priority’, which states that a plant must be known by the earliest published name, the name hosta was reinstated.
Most name changes which are occurring now are due to improved scientific research and the desire to categorize plants based on genetic information rather than the opinion of individual botanists. In the past, plants were grouped together generally on the basis of shared visual characteristics of the plant, seeds and how the plant reproduced. Botanists are now reclassifying many plants as improvements in microscopy, biochemistry and genetic research improve the understanding of how plants evolved and relate to each other.
It has been only in the last year or so that I have become aware of just how important a regulated and agreed universal system of botanical names actually is. Writing a book which will be sold in other countries has certainly opened my eyes to the complexities of plant naming and the importance of people knowing which plant you are referring to. Despite the Latin system it’s surprising how many plants are still known more readily by a common name, sometimes this can be complicated further by some names being used only in particular countries. Then, of course, there are some plants which have no common name and the Latin is the only way we know the plant. What we’ve ended up with is a remarkably confusing situation which has been complicated further in recent years with the advent of DNA research. For instance, the silver-leafed plant Senecio cineraria more commonly known, particularly in the US, by the name dusty miller should now be known as Jacobaea maritima. Then there are the Michaelmas daisies, Aster novi-belgii and Aster novae- angliae, which it has been decided will now be known as Symphyotrichum novi-belgii and S. novae-angliae and Schizostylis coccinea, or the kaffir lily, which now goes under the name Hesperantha coccinea.
For my books my editor uses the RHS Plant Finder and/or RHS A-Z Encyclopedia of Garden Plants as her guides but even then life isn’t simple. The house style of my publisher asks that a plant has the Latin name used when the plant appears in the text for the first time and then subsequently it can be referred to by the common name. But which common name to pick? Would you know what ‘Harry’s walking stick’ is? Well I didn’t. Turns out it’s another name for contorted hazel. Fortunately there is a degree of flexibility and I have a very understanding editor, so we went with contorted hazel in the end.
So who decides what name a plant will go by? Well, committees of botanical experts meet to discuss potential changes every 5 or 6 years at the International Botanical Congress. Often a botanist will suggest a plant doesn’t belong in the genus it is currently in but it can take years 20 or 30 years in some cases before the idea has picked up enough momentum to be accepted. Changes can also be blocked if it’s believed it could be detrimental; crops in particular tend to be protected from botanical name changes. Imagine the impact name changes could have on areas of the horticultural trade. If, for instance, the name of petunias changed, as was suggested at one point, how would this affect the vast business in bedding plants? Would they continue to use the name petunia thereby making the change seemingly pointless or adhere to the new name and risk losing business if customers didn’t know what they were buying?
So what does all this mean for gardeners? Certainly the need for a regulated and universally accepted system of plant names has never been greater and not just for scientists. As many more gardeners are communicating about growing via social media and blogs we all need to be able to know which plants were are writing about. It does seem to me a little odd though that the system we have means it is easier to revert to a plant’s common name despite all the inherent problems this can cause. And as plant names come under further scrutiny with changes arising it seems more likely that we will continue to use common names. Some plants now have two Latin names, the old one and the new one, and a multitude of common names. I’m not sure this is the ordered system that Linnaeus had in mind. However, I do see that plants placed in groups based on their genetic make-up seems the most logical and useful way of classifying them.
Human nature is generally conservative, we rarely like change and certainly change that makes life more confusing or difficult, even if it’s just in the short-term. I was of a generation which was taught metric at school but I have parents who still use imperial, as a result I have grown up using a mix of both and still favour imperial in certain circumstances. It shows that just because it has been decided that something is the accepted and recognized way of doing it, it can take a long time for changes to filter down and be used by everyone. In the mean time there’s a muddle where both systems have to run alongside each other. Acidanthera is no longer and should be referred to as Gladiolus murielae instead but how many bulb catalogues have made the change? How long it takes for name changes to become accepted outside scientific circles is hard to know but one thing we can be sure about is the world of taxonomy is going to get a lot more confusing.