I found this strange-looking dandelion in Newcastle this afternoon, growing beside a footpath in the city. Unlike typical dandelions (see picture below) which have a spiral whorl of florets each with as single long petal with a toothed tip, with very long petals around the margin of the flower head, this one had very short spoon-shaped petals throughout, so the flower resembled a pom-pom with numerous long styles, each tipped with a bifid stigma, sticking out of it. Quite decorative for a dandelion. There are mutant varieties of chrysanthemum sold commercially that are very similar in form - but a lot larger.
This (above) is a typical dandelion inflorescence. Normally each individual dandelion floret is quite a complicated affair (see here for details) with the long style elongating through a tube of pollen-laden stamens, followed by the splitting of the stigma tip to reveal its receptive surface - a complex arrangement that is totally redundant because dandelions set seed without the need for any fertilisation by pollen, by a process called apomixis. The seeds that are produced are all clones of the parent - so in a week or two, when the flowers have run to seed, I'll go back to this abnormal plant and collect some - they should breed true and produce exact copies if this is a genetic mutant.
The other curious aspect of this mutant, seen here from above, is that all the florets are female - there is no trace of stamens or pollen. It seems the mutation that truncates the petals also inhibits the development of the stamens.
There's more on dandelions here.
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