Identifying and recognising wildflowers.

Monday, Nov 17, 2014 at 13:47

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Many of us are collectors when we travel. Rocks, pubs, minerals, wildflowers - you name it, someone will be out there collecting it. Or gathering photos of it, intending one day to put a name to it. Putting names to all kinds of “things” contributes to our ability to learn and communicate. Names give identity. They help us to distinguish between the myriad of objects we experience and to slot them into our memory and the context of our lives. Whether it’s people, vehicles, stamps or wildflowers, they all need names.

When it comes to wildflowers a couple of frequently asked questions are “how can I find a name for this plant” and “What is a good book for wildflower identification?”

Those apparently straightforward questions have no easy answers. Instead they open up a whole raft of other questions and ideas, and I will try to make some sense of them in this and the following blogs.

The process of naming living things has a whole field of scientific study devoted to it. I will explain a bit about how plants are named in the next blog. For now it is sufficient to know that naming plants (or animals) relies on very detailed examination and description of all the parts of the plant and comparing similarities and differences between similar looking plants. Some of the features that are examined and described might be large and obvious like the number of petals in a flower. Other features might be tiny, even microscopic like the shape of the hairs on the underside of a tiny leaf.

The particular features of interest will vary between groups of plants, but in general once we have described the plant and pinned down the differences and similarities with other plants we can begin to classify, identify and name it. And then, when we have identified and know the name of a plant we may be able to recognise it next time we see it, based simply on its overall appearance.

That distinction between identification and recognition might seem trivial but in reality they are quite different processes. Identification relies on being able to say “why” a plant (or dog, a person or your lost wallet) is named as it is, based on specific details. Recognition relies on comparing an object (or person, etc) with a composite impression or idea held in your memory or with external images in a book or website. To illustrate, you might recognise your missing dog by his overall (gross) appearance, even at a distance. But to identify him – to say “why” he is your dog - you need details of specific features – a missing tooth, a collar tag, a scar on his belly, features that require much closer examination.

The books and websites we use to help us put names to plants take different approaches to reflect that difference between identification and recognition. In practice a layman will use mostly recognition to put a name to a wildflower, while an expert will use both identification and recognition.

To describe all the intricacies of a plant – the size, shape, colour, structure, texture and arrangement of all the bits – involves the use of an extensive technical language, and many plant books have some sort of glossary of these terms to help us. Unfortunately understanding the gradations and distinctions between a bewildering array of terms will only be mastered by continual use and experience, activity that tends to be impractical for the average wildflower enthusiast.

But there are many books, usually called a Flora or Field Guide, that make use of these accurate descriptions to compile a list (with descriptions) of plants in a given area – ranging from a small locality to a state or even Australia-wide. Their intended audience is students, researchers and others who might at some point be regarded as an expert in that area. “Handbook of the Vascular Plants of the Sydney District and Blue Mountains” by Beadle, Evans and Carolin and “Flora of the ACT” by Burbidge and Gray are a couple of examples that I cut my non-expert, student botanical teeth on.

A variation on the Flora or Field Guide is the publication that deals in depth with one group of plants eg wattles, grasses or “The Eucalypts” in 3 volumes by Brooker and Kleinig.

An integral part of such floras or field guides is a Botanical Key, which is a device for comparing the descriptions of individual elements of a plant. A key requires the user to choose between pairs of features – are the flowers red or blue, are there 5 petals or 6, are the hairs a simple filament or star shaped? Some keys are fairly simple (but often less accurate), such as those that deal only with the larger readily observed features of the plants in question. Others are very complex (and probably more accurate) requiring dissection, and examination and interpretation of minute, even microscopic features.

Keys work best when they can be used with plenty of freshly collected plants to examine. Trying to identify a plant from photos by using a key is problematic at best as the crucial features are often not visible in the photos.

Publications and websites that rely on keys and accompanying detailed technical descriptions have little need of illustrations and colour photos. Older keys may have used cheaper line drawings to supplement the text, but with improvements in colour printing increasingly some photos are used to illustrate particular features. Once a positive plant identification has been made using a key it is then possible to recognise that plant again without going through the laborious keying-out process.

Publications and websites that make use of numerous large photos accompanied by rather less descriptive text mark a shift away from identification and towards recognition by enabling readers to recognise plants from their overall (gross) features. It can be relatively simple to match your photo with one in a book or on a website, although the accuracy of that process can be limited. Some examples to illustrate: small or hidden features of a plant may not show in a photo, limiting the certainty with which an accurate name can be given; many plants only grow in quite localised areas, so unless you know where your plant came from accurate naming may be difficult. And accurate naming often relies on features like seed pods or fruits, structures possibly not present when you took your photo of the flower.

However the biggest limitation to accurately naming plants by matching photos is the sheer number of plants in existence. There are an estimated 25,000 to 35,000 plant species in Australia. There are around 2800 species of eucalypts (gum trees) alone, and about 1000 species of acacia (wattles). Then there are the myriad of peas, daisies, lilies, grasses, grevilleas … the list goes on. (Best not mention the estimated 250,000 species of fungi…)!

Fitting good quality photos of all those thousands of plant species into one book or even a whole shelf of books would be practically impossible. Websites clearly have more capacity; their limitation is more likely to stem from the human and financial resources able and available to populate them. Consequently plant publications of the “recognition” type tend to feature the more common, widespread or photogenic plants. It follows that accurately naming a plant from what must of necessity be a limited selection of photos is not always possible.

By contrast, there are about 400 Australian mammals. There are between 800 and 900 species of Australian birds and a similar number of Australian reptile species. With those numbers one thickish book for each of those 3 groups could accommodate detailed descriptions and a set of photos for each species. What a contrast to the plants!

For all their limitations books remain a staple resource for wildflower hunters, although increasingly websites are proving valuable too. But there is not, and never can be, one book for all the plants. We need a selection of books, and understanding the different types and their intended audience helps make our choices more effective. So we build our libraries and sometimes carry a bulky selection of books with us when we travel.

But turning pages in a quest to put a name to a flower is a slow process. A shortcut is needed and one is available, via a centuries-old system of plant classification. It just takes a bit of basic botanical knowledge to cut out much of the tedium of page turning.

I’ll get to that in the next blog.
J and V
"Not everything that can be counted counts, and not everything that counts can be counted."
- Albert Einstein
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