To the west of Malham Tarn is Tarn Moss which drains into the tarn proper. It varies from a species rich low-lying fen to a species poor raised bog. The former is at pH7 and the latter pH4. Such a change can occur in just a few metres. The raised bog must be at least 1 metre higher than the species rich fen. Lots to discover, but principally an understanding of sedges (have edges), rushes (are round) and grasses (have leaves to the ground) is needed. Obviously it was also necessary that one clot fell in the bog - myself.
Looking and walking over this fen-bog I was reminded of the land around the Somme in Picardie, or rather Edmund Blunden's description of trying to fight the Great War battle of that name in such terrain. As you may guess the Germans were on the higher, drier ground with good observation and the poor bloody infantry of the BEF were often fighting through something that is described, at least by Blunden, as like this fen-bog.
We put down our quadrant and start to identify by keying out the specimens using ... erm ... Stace! Interesting to think that Darwin himself came up with this rectangular frame idea: throw it on the site at random; identify and count what is in it; do this several times; bulk up the figures for an average - well, basically that's it.
Common Spotted Orchid I'd say (dactylorhiza fuchsii). Lots of these, so big search on for the Northern Marsh Orchid.
But for ordinary mortals lots of Round-leaved sundews to delight (Drosera rotundifolia).
Duck-boarding over the raised bog.
A grass (I think!) showing female and male parts alternately.
And this sedge propagates by rhizomes which characteristically grow in fairly straight lines ...
Marsh Lousewort (Pedicularis palustris)was well distributed in part of the fen. This is in a group of hemi-parasites partly depending on the roots of other plants for nutrients.
So we trudged back to the great house for dinner, late as usual for the six o'clock bell.
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