Friday, 17 January 2014

Re-analysing our Plant Hunt data. 

Musk Stork's-bill flowering in Lincs
Image: S. Lambert
Members of the public have started reporting 'first sightings' of plants in flower over the past few days, leading some media commentators to wonder if this is evidence that spring has come early this year. 

Tim Rich, Co-ordinator of BSBI's New Year's Plant Hunt, was a little surprised to hear this: it did not chime with the findings of BSBI botanists and members of the public who recorded what was in flower over the New Year period. So, he re-analysed the data in terms of spring- summer- and autumn-flowering species. This is his comment on what he found:

Red Dead-nettle flowering in Wilts.
Image: T. Havenith
"Whilst a very few spring flowers can be found flowering early, the dominant feature of the winter weather is the late mild autumn with lack of frosts which have allowed an amazing 221 species to be recorded flowering by members of the Botanical Society of Britain and Ireland over the New Year period.

Of the 221 species recorded only 8 (3.6%) were typical spring-flowering, native species such as Primrose or Lesser Celandine, and these represented only 2% of the 1075 total records.  

In contrast, species continuing to flower from the autumn such as knapweed or yellow-wort made a massive 91% of the species in flower (69% of the records overall).  

Ten species (4.5%) were those which typically flower all year such as Groundsel or chickweed (28% of all records), and one species, winter heliotrope, normally flowers during the winter.

Just as one swallow does not make a summer, a few snowdrops do not make an early spring".

Many thanks to Tim for doing this re-analysis. So, which are you seeing in your neck of the woods: early spring flowers or late autumn flowers?