The diversity of dandelions
18 May 2012
The extraordinary biodiversity to be found even among garden weeds has been highlighted by the discovery that there are more than 100 different species of dandelion growing just in the Cardiff area. Two of those found during the study carried out for the National Museum of Wales may be new to science.
Gardeners may think there is only one type of dandelion: generally known as Taraxacum officinale, the type best dug out with a fork while weeding. In fact, T. officinale is a rare species found mainly in Scandinavia, where it was originally collected and named by Carl Linnaeus. In the garden, it's far more likely to be one of the hundreds of other species of Taraxacum, some endemic to the UK and others arriving from abroad.
'There's rarely just one in each garden,' said taxonomist Dr Tim Rich who carried out the survey, 'I was just astonished at the sheer diversity I found in Cardiff – when you speak to people they say they didn't realise there were more than one.'
Using a collection of 560 species held at the Museum, Tim discovered 15 species just in the lawns outside the building. He uncovered a further eight in his own garden and 12 more on nearby verges, eventually identifying 102 different species.
Many had particular adaptations to suit a particular habitat: the native T. britannicum, for example, is a smaller, more delicate low-growing species which does well in dry, exposed positions like cracks in paving stones, while species like T. ekmanii grow taller and more vigorously to compete with other plants in meadows.