07 June 2011

Annual Knawel

The hill above Penclawdd is currently the only known location in Glamorgan for the rather unobtrusive Annual Knawel (Scleranthus annua) which has not been seen since Quentin Kay reported it as abundant here in 1992. I visited the site last year and failed to find it, which was hardly surprising as it was pretty much ungrazed wall-to-wall Hedge-mustard (Sisymbrium officinale) as shown below. However this year the condition of the field was much more suitable, having been disturbed and grazed and in a 15 minute lunchtime search I managed to locate about 20 plants.

Left, field in 2010 and right, the same field in 2011 

Also lots of Knotted Clover (Trifolium striatum) in the field.


Nigel Ajax Lewis said...

It is a real novelty to refind a
SECTION 42 LIST OF SPECIES OF PRINCIPAL IMPORTANCE FOR CONSERVATION OF BIOLOGICAL DIVERSITY IN WALES in Wales Biodiversity Week in a 15 minute lunch break on its only apparent recorded site in Glamorgan. Poor old unobtrusive Annual Knawel is entirely at the mercy of the landowner's ability to find grazing animals for that site at the right moment and whoever they are, are probably entirely ignorant of the treasure they have.
And worse, nobody will necessarily want to tell them in case they destroy the colony, unless they are given a grant to manage it.

Barry Stewart said...

I'm guessing the seed must remain viable for a good few years and the population is prone to fluctuations, but hopefully this year's seed production will be enough to tide it over until conditions become favourable again.