Tuesday 26 March 2013

Ynyslas

The sand dunes at Ynyslas were bleak and wintry when I visited yesterday. The easterly wind whipped across the flat plain of Cors Fochno and down the Afon Dyfi from the snow covered hills to the east. The bus dropped me at the concrete shack 'Ynyslas Turn' and I walked the remaining mile toward the dunes. A row of small grey bungalows interspersed with misplaced two-story goliaths protected me from the worst of the wind. These soon petered out giving way to an uninviting caravan site with a hopeful advertisement for Sunday dinner. The dune slacks were completely flooded condemning my plans to search for the minute dune slack liverwort Petalophyllum ralfsii. I headed toward the bare sand of the rabbit-scrapes to search for winter annuals. 

Among the russet patches of Syntrichia ruralis subsp. ruraliformis there were many plants of the Little Mouse-ear, Cerastium semidecandrum distinguished from the few plants of Sea Mouse-ear, Cerastium diffusum by the scarious tips to the bracts that are just visible in the picture below.             


Cerastium semidecandrum, Ynyslas, SN 60889401, March 2013

Moving deeper into the dunes I encountered an abundance of  Lesser Chickweed, Stellaria pallida crawling around on the bare sand. This small diploid relative of the Chickweed, Stellaria media is frequent on sandy ground around most of the British coasts as can be seen from the distribution map. This species is mostly cleistogamous meaning that each flower pollinates itself without opening. 


Stellaria pallida, Ynyslas, SN 60889401, March 2013

Moving back to the margins of the flooded slacks the creeping sand dune form of the Variegated Horsetail, Equisetum variegatum was abundant its tough, white banded stalks topped by small apiculate cones. 


Equisetum variegatum, Ynyslas,
SN 60889401, March 2013

Nearing the deserted visitor centre the signs of rabbit activity peaked on a small dune riddled with burrows. Among the mess of loose sandy warrens were the young leaves of Houndstongue, Cynoglossum officinale. This mainly southern species has its only Cardiganshire station at Ynyslas.

Cynoglossum officinale, Ynyslas,
SN 60889401, March 2013

I took a few steps out on to the estuarine sands but was rebuffed by clouds of airborne sand on its way to catch among the Marram. Defeated by sand and wind, I cut my visit short.   

Verkleij, J. A. C., AM de Boer, and T. F. Lugtenborg. "On the ecogenetics of Stellaria media(L.) Vill. and Stellaria pallida (Dum.) pire from abandoned arable field." Oecologia 46.3 (1980): 354-359.

Friday 22 March 2013

Constitution Hill, Aberystwyth

Aberystwyth lies at the centre of Cardigan Bay and, therefore, also at the midpoint of the Welsh coastline. A small seaside town with a picturesque Victorian promenade Aberystwyth is populated mostly by students and aged holiday makers. It is bounded north and south by a pair of small hills with that to the north being  Constitution Hill. Composed of friable sedimentary rocks know as the Aberystwyth Grits this small hill is scaled by a short funicular railway and is topped by a run down cafĂ© complex.

Loose shaley areas at the bottom of the cliffs just above the pebble beach support the fleshy maritime subspecies of Common Sorrel, Rumex acetosa subsp. biformis. Unusually for a subspecies this taxon has been granted a common name: Overlooked Sorrel. As can be seen for the BSBI distribution map this moniker is well deserved. The preponderance of Cardiganshire records is a frequent anomaly for critical taxa and is the result of one botanist. Arthur Chater lives in Aberystwyth and has, during his 35 years as county recorder made Cardiganshire one of the most thoroughly recorded counties in the UK. His recent book, Flora of Cardiganshire, is a heavy slab of detailed information on the flora and botanical history of the county that sets the standard for county floras.         

Rumex acetosa subsp. biformis Constitution Hill, Aberystwyth.
SN 58284 82617. 17/03/13
  

Also among the shale are a few plants of the beautiful coastal species Yellow Horned-poppy, Glaucium flavum. The leaves of this species are coated in a thick growth of multicellular hairs giving them a hoary appearance. This coupled with the leaf's waxy surface makes the plants 'almost unwettable' (Scott, 1963) an important adaptation for a species that is often subject to salt spray or inundation. 


Glaucium flavum Constitution Hill, Aberystwyth.
SN 58284 82617. 17/03/13

Slightly further up the slope the bright little flowers of Coltsfoot, Tussilago farfara are already peaking trough the grey of the scree. This pioneer species produces flowers early in the spring before the leaves have developed.


Tussilago farfara Constitution Hill, Aberystwyth.
SN 58281 82636. 17/03/13

At the top of the hill an area of trampled ground with perforated rubber matting supports a diminutive community. As seen in the picture below the tiny plant Blinks, Montia fontana is in flower and Sea Mouse-ear, Cerastium diffusum is budding among the moss.

Montia fontana & Cerastium diffusum 
Constitution Hill, Aberystwyth.SN 58281 82636. 17/03/13

A frequent occurrence on the rocks of Constitution Hill is the moss Coscinodon cribrosus. This small moss is local in the British Isles mainly occurring on the western coasts. It forms small white tipped cushions on shaley rocks.


Coscinodon cribrosus Constitution Hill, Aberystwyth.SN 58281 82636. 17/03/13


Scott, G. A. M. "Glaucium flavum Crantz." Journal of Ecology 51.3 (1963): 743-754.