Why botanists avoid dandelions

I love dandelions. I love the sight in April of a grass verge or bank just covered with these little blobs of sunshine.

A simple flower to identify, you might think. Ha! From a botanist’s point of view, they are generally a no-go area. There are actually over 230 species of dandelion in Britain. “What!”, I hear you say, ‘They all look the same!”. Well, yes, that’s the problem. Actually, they don’t all look the same when you start looking at them, but even when you can see the differences only a few of them are easy to assign to a species without the help of an expert or an awful lot of practice (and patience). Vegetation surveyors generally put Taraxacum agg. for any dandelions they come across – “Taraxacum” being the genus name for dandies, and “agg.” standing for “aggregate” – so, in other words, “one of the many dandelion species and that’s as far as I’m prepared to go”, and they quickly move on!

So, how come there are so many very similar species?

Unlike most plants, most dandelions, in the UK at least, don’t do sex. They reproduce by seeds, but these seeds develop without fertilisation, so the genes of the offspring plants are identical to those of the mother plant – they are clones. For those technical types or those who just like interesting words, this is known as apomixis (dandelions are apomictic). Brambles and a few others do the same thing. A new species could arise if a mutation were to happen that made the dandelion sufficiently different. That difference would be perpetuated in its offspring, as all the offspring would be clones of the new dandelion. Not all dandelions are apomictic, and it is thought that some pollen-bearing apomictic dandelions may have hybridised with non-apomictic dandelions at some point in the past, so starting off more lines of clones. Because the differences between these species tend to be small, they are sometimes referred to as “microspecies”.

If you’re still with me after that all that fun biology and haven’t gone for a lie down in a darkened room, another interesting fact about dandelions that you may not realise is that the “flower” is actually made up of lots of tiny flowers, each with their own reproductive parts. It has fused all five of its petals together into one long "petal". The white "hairs" (pappus) around the base splay out to form the dandelion "clock" to help disperse the seeds when ripe.

For most botanists, where dandelions are concerned frankly life’s too short! And that was certainly the case for me. Things changed somewhat with lockdown. Faced with very little to get my botanical teeth into, I decided to dip a toe into the murky world of taraxacology (posh word for looking at dandelions). And while I can confirm that, yes, that way madness lies, amongst all the frustration as well as the strangely addictive nature of it, I managed to find one species that was the first ever record for the vice county and two others with very few records and none anywhere near me – not because the dandelions weren't there before, of course, but because no-one around here has dared, or been daft enough, to look before.

Anyway, now you know why botanists avoid dandelions!

Page from my sketchbook recording the first dandelion I managed to identify, White-Stalked Dandelion (Taraxacum leucopodum)