Sunday, September 17, 2023

Quillwort at Llyn Carw


Llyn Carw - about 6 km trek across difficult moorland from Dolymynach.

The Cambrian Mountain Society teamed up their walking expertise with botanists last week on this walk to our most remote lake. 

Quillwort was found there in 1979 by Ray Woods and determined to be the rather more rare Spring Quillwort, Isoetes echinspora by S G Harrison at the National Museum of Wales. (He was a co-author of the book that describes them for Wales.)

It was at that time “Common on north and west margins”.

Gill Foulkes, a botanist member of the recent expedition, did find a Quillwort on the other side of the lake. (None was found where the original sample was taken.)

Here it is:
The Quillwort found by Gill Foulkes last week, which turned out to be Isoetes lacustris

You have to sacrifice a leaf to prove it's a Quillwort:

And knowing which one needs these megaspores to be examined:
They are about 0.5 mm across...

So maybe the lake does actually still have both of these Quillwort species (the north and west has the more suitable habitat for Spring Quillwort).

Further expeditions are required!

And the members of this walk did prove that botany and long walks can be compatible - with a good recce prior to the day...

Friday, September 01, 2023

An exciting find and other matters

 A record popped up on iRecord last week that is a great new find for the Vice County.

We already have the most southerly occurrence of Circaea alpina (Alpine Enchanter's Nightshade) in the British Isles I think but our one small (and somewhat struggling) population at Craig y Cilau is now joined by a substantial and healthy population found by Sam Thomas while visiting the (also very rare) population of Sorbus stenophylla near Capel y Ffin in the Llanthony valley.

Circaea alpina (Alpine Enchanter's Nightshade) picture, Sam Thomas

Sam said "The rain was torrential and we started from the top which was an unwise choice, once we'd seen the Sorbus we decided to cut straight down the cliff to escape the rain as quickly as possible. We found the Circaea on the way down. It was in a very inaccessible location so not that surprising that it hadn't been found before."

There are a good number of plants on at least two levels of a small, mossy flushed cliff . The Brecknock Botany Group will be visiting next year in early July to collect a herbarium specimen and see it for themselves (those up to the intrepid climb...)

Another picture by Jacques Turner-Moss 

In other - less exciting news, the group have been filling in some upland under-recorded tetrads - sometimes with surprising finds - and certainly with many extra map dots for axiophytes of the county.

We have noticed that this year's weather has really suited Hypericum humifusum with many more records than usual of much larger and well-spreading plants than we usually see.

Hypericum humifusum, Trailing St John's-wort above the Irfon river