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Although C. echinata is such an obvious sedge, it is, IMHO, always good to get into the habit of looking at the key ID features where sedges are concerned. Start by looking at how many spikes there are on a stem. If two or more (as there are here - one can just see the second pike on the photo) then are they all similar or not? If they are (as here) then count the stigmas - 2 = subgenus Vignea, 3 = subgenus Atratae. It's difficult to see the stigmas on the photograph and the plant is obviously past its best, but the nuts are clearly biconvex, so two stigmas it is. Then normally it's a keying task!
BSBI VC Recorder
Taxonomy Link is wrong for this one
Carex muricata subsp. muricata
..in the Problems section of the Forums.
I can confirm this is Star Sedge
Similar to http://www.ispotnature.org/node/341832
Lat/Lng: 52.1, -3.4
OS grid ref: SO0451