Sunday 21 August 2016

YNU Meeting at Colt Park - incl - Klebsormidium crenulatum

The YNU Vice County 64 Field Meeting held at Ingleborough  on 20 August 2016 had weather designed to cancel out the three hot sunny days earlier in the week.

Actually the venue- Colt Park Barn - Natural England - was an excellent base. It meant that those who wanted to, could stay indoors in the afternoon, using microscopes if necessary, to look up details about the plants and animals we had found.
On the left is Derek Whitely who had come up from Sorby Natural History Society

I even made a start at listing the mosses I had brought back in a bag... and was informed that the tiny woodlouse (c 4mm long) I had  found in my Philinotis fontana (moss) was in fact Trichoniscus pusillus the Common Soil Woodlouse, which is the commonest woodlouse in Britain. 
We (well Roger Neale) also found the Rosy Woodlouse Androniscus dentiger which is pink, up to 6mm long and is much less common and lives in lime rich conditions - from caves to brickwork.

Our group had restricted our botanical recording to a small area that had recently been fenced off to protect newly planted native trees beside a steep streamlet.    The thicker soil had Heather (Calluna vulgaris)  and Green-ribbed Sedge (Carex binervis); other areas had calcareous flushes with Bird's-eye Primrose (Primula farinosa), Lesser Clubmoss (Selaginella) and Butterwort (Pinguicula vulgaris).

We found Bristle Clubrush (Isolepis setacea)  about 100 m to the north of the fenced off area, where the path crosses a parallel gill.
This may be the first record for that field

Klebsormidium crenulatum
On the return to the barn we passed through a gate at the top of the field. the wall there was made of sandstone.. and many of the stones had Klebsormidium crenulatum  -  the filamentous green alga that is increasing in Britain due to increased nitrogen oxides in the air. (See my other records of Klebsormidium)

Saturday 20 August 2016

Agrostis canina - Velvet Bent

Velvet Bent has a typical Agrostis "Christmas tree panicle with tiny spikelets", but the spikelets usually have awns  (Use a lens).  The leaves are narrow, usually less than 2mm wide, and the ligules are long and narrow. 

The emerging leaf is rolled and hairless (as in nearly all other Agrostis species)

Agrostis canina grows in damp/wet low nutrient places, - 
often with rushes.  

It has stolons with several shoots growing at each node- so the shoots and leaves are slender and tiny. With so many shoots and leaves growing close together it looks like velvet.

It is easier to observe this late in the summer, when the stolons with their side shoots have had time to grow.

A. canina at Thornton Ellers (Lower Derwent Valley NNR)
20 July 2016

A. canina at Thornton Ellers

Comparison with similar species:- 

Agrostis stolonifera also has stolons. It has one side shoot per stolon node, and its blades are usually greater than 2mm wide, whereas:
  Agrostis canina has several shoots per stolon node and the blades are less than 2mm wide.

A. canina at Straloch Moraine, Kindrogan July 2016,
growing amongst rushes.

Closer view

From my experience the panicles are often a little more  open than the extremely similar panicles of Agrostis vinealis.
However A vinealis has short rhizomes, with about 3 white scales on the rhizome before it turns upwards and forms a new  green leafy shoot.

Agrostis vinealis - Brown Bent