Easily confused with : five other sub-species of Kidney Vetches, if you can find them. Sub-species, according to BSBI. Two are in decline and have not been spotted in the UK for decades, the others are still around in some places. Luckily, none of the others are to be found where your author found the most abundant of Kidney Vetches, the one detailed here.
Distinguishing Feature : A flower-head consisting of a small ping-pong-sized fuzzy balls with numerous small yellow Pea-Family like flowers protruding from what looks like a ball of cotton wool. Very distinctive. A unique feature were it not for the fact that there are another 5 sub-species, probably all looking much the same.
Kidney Vetch is highly variable, with flowers varying from pale to deep yellow, orange or scarlet-red. It is quite possible that the photos from the Caldon Canal represent the sub-species anthyllis vulneraria ssp. polyphylla, but since your Author can find no photographs of this sub-species, it can only be an educated guess based on nothing more than the BSBI distribution map.
BSBI distribution of sub-species anthyllis vulneraria ssp. polyphylla. On the other hand, it might not be.
There are 5 sub-species of Anthyllis vulneraria :
which may explain away most of any observed variability. However, these sub-species are themselves variable and several specimens should be examined before any conclusion is reached (if any can be). They differ only in subtle ways to do with the hairs, whether appressed or not, the calyx whether tipped with red or not, the colour shade of yellow of the corolla, the exact arrangement of the leaflets, and whether the leaves look 'kind of' succulent or not. All airy-fairy stuff.
- ssp. carpatica which occurs in only a few hectads scattered around the UK except Eire.
- ssp. corbierei which hasn't been seen since 2009 and then only in one hectad near Penzance. [RRR]
- ssp. lapponica which occurs in a few scattered hectads in Scotland and especially Eire near Wexford. [RR]
- ssp. polyphylla which occurs in only a few hectads scattered around the UK except Eire. Is more leafy with bigger leaves than ssp. vulneria
- ssp. vulneraria which is the modal species.
On top of that the ssp. vulneria appears to be sub-divided into differing varieties:
which differ in even more subtle ways from ssp. vulneria.
- var. coccinea
- var. langei
- var. iberica
- var. pseudovulneria the modal variety.
So the Author hopes the Reader will forgive him for not identifying the exact sub-species and variety that the above specimens represent, although it seems a good bet that most are of ssp. vulneraria var. pseudovulneria. Maybe...
It prefers a dry habitat, on sea cliffs and mountain ledges or open limy grassland. The specimens proliferating at the Southport locality are all on very sandy vegetation-covered soils just above the high-water mark, so it will be salt-tolerant.
Almost the whole plant, especially the flowers and flower-heads, are covered in long soft white hairs. This is not a pappus, however, the seeds are not, as far as your Author knows, borne by the wind. Gale Force 10 or Hurricane maybe...
Often grows close to the sea above the high-water mark, or on sea cliffs or dry and open chalky grassland. Also on mountain ledges, although your Author has never seen it there, but maybe that's because he tends to avoid dangerously steep places on mountains.