CROWN VETCH

Securigera varia

Pea Family [Fabaceae]

month8jun month8june month8jul month8july month8aug

status
statusZneophyte
flower
flower8bicolour
flower
flower8white
flower
flower8pink
flower
flower8purple
flower
flower8mauve
flower
flower8blue
morph
morph8zygo
petals
petalsZ5
type
typeZclustered
stem
stem8round
toxicity
toxicityZhigh

8th July 2016, railway sidings, Ellesmere Port, Cheshire. Photo: © RWD
A neophyte growing to 1.2m (or more as here) which is naturalised in grassy and waste places, such as this still-used (but in-frequently) railway line.


8th July 2016, railway sidings, Ellesmere Port, Cheshire. Photo: © RWD
Has a profusion of parti-coloured flowers and pinnate leaves.


8th July 2016, railway sidings, Ellesmere Port, Cheshire. Photo: © RWD
The flowers are on multiply-branched and very long stems (far longer than the stems of the leaves). The flower stems branch singly, not in opposite pairs.


30th June 2016, railway sidings, Ellesmere Port, Cheshire. Photo: © RWD
Flower heads almost spherical when fully opened. Leaves pinnate with between 11 to 25 leaflets.


8th July 2016, railway sidings, Ellesmere Port, Cheshire. Photo: © RWD
The stems and leaves are glaucous-green when mature, a brighter green when newly forming near ends of stems (bottom).


30th June 2016, railway sidings, Ellesmere Port, Cheshire. Photo: © RWD
Several new flower-heads with green folded-down flower-buds which radiate from the end of a stalk. A really new very small flower-head is developing near the centre of the photo, slightly to the right.


30th June 2016, railway sidings, Ellesmere Port, Cheshire. Photo: © RWD
Leaves pinnate with terminal leaflet. The plant manages to scramble despite lacking all tendrils (unlike all true vetches, which do possess tendrils).


8th July 2016, railway sidings, Ellesmere Port, Cheshire. Photo: © RWD
Flower-buds radiate out on short stalks from the tip of a stem, growing larger from the very tiny ones on the left to a nearly fully grown one on the right.


30th June 2016, railway sidings, Ellesmere Port, Cheshire. Photo: © RWD
Flowers in various stages of opening up: flower buds curled over downwards (bottom left), flower bud spreading outwards ready for opening (right)


30th June 2016, railway sidings, Ellesmere Port, Cheshire. Photo: © RWD
The sedal tubes are toothed and green. A liitle hint of colour is replacing the creamy-greenness of the developing flowers buds.


8th July 2016, railway sidings, Ellesmere Port, Cheshire. Photo: © RWD
Flowers at the top of the flower-head nearly ready for opening, those ones beneath having already opened.


8th July 2016, railway sidings, Ellesmere Port, Cheshire. Photo: © RWD
Flowers fully open (as much as they ever do fully open) with narrow (here pink) banner atop and two (here white) wings clasped together hiding within the two smaller keels, 5 petals in all. The styles are slightly protruding out between the wings. Supposedly with between (5) 10 to 20 flowers, but these clearly have quite a few more than 20, perhaps it is more of a garden variety?


19th June 2004, Goldthorpe, South Yorks. Photo: © John Phandaal Law
Bird's-eye view. A ring or crown of small pea-type flowers, which in this instance are pink, but can be of any colours between blue and red including white. A straggling plant that can get to 1.2m in length, but not bolt upright. This specimen from Goldthorpe conforms to the 10-20 flowers in a flower-head.


8th July 2016, railway sidings, Ellesmere Port, Cheshire. Photo: © RWD
The flowers are bi-coloured, with a choice between white, pale lilac, pink, mauve or purplish.


8th July 2016, railway sidings, Ellesmere Port, Cheshire. Photo: © RWD
Flowers now spent, petals withering away and dropping off. Long thin green pods develop and elongate, still with long (white) style and stigma attached.


8th July 2016, railway sidings, Ellesmere Port, Cheshire. Photo: © RWD
Most petals have dropped off, the thin roundish green pods elongate and begin to stick upright.


8th July 2016, railway sidings, Ellesmere Port, Cheshire. Photo: © RWD
Long thin 4-angled pods emerge from the toothed sepal tubes. Flower stalks now a lime-green.


8th July 2016, railway sidings, Ellesmere Port, Cheshire. Photo: © RWD
Mature pods sticking bolt-upright. Pods are beaded (the seeds within) having between 3 to 8 (up to 12) segments.


8th July 2016, railway sidings, Ellesmere Port, Cheshire. Photo: © RWD
Pinnate leaves in abundance.


8th July 2016, railway sidings, Ellesmere Port, Cheshire. Photo: © RWD
Mature leaflets are long-oval (elliptic to oblong), entire (untoothed) and with a short point at the end. They are glaucous-green top and undersides. Leaf rachis has a groove on the upper surface. Between 11 to 25 leaflets are widely spaced on the rachis, including a terminal leaflet. Leaflets 6 to 20mm in length.


8th July 2016, railway sidings, Ellesmere Port, Cheshire. Photo: © RWD
Undersides of leaflets are a paler glaucous-green.


8th July 2016, railway sidings, Ellesmere Port, Cheshire. Photo: © RWD
Matted white hairs on underside of leaflets account for the extra pallor of the undersides. Prominent central mid-vein, other side-veins hardly discernible. Leaf rachis has very short hairs. Leaflets have short stalks.


8th July 2016, railway sidings, Ellesmere Port, Cheshire. Photo: © RWD
Branch nodes have two short ligules. Thicker main stems are pronouncedly ribbed.


30th June 2016, railway sidings, Ellesmere Port, Cheshire. Photo: © RWD
New Seedlings. Leaves glaucous green contrasting with the bright-green of the moss upper right.


Uniquely identifiable characteristics

Distinguishing Feature : A circular display of small pea-type usually bi-coloured flowers arranged like a crown.

The above photos from Ellesmere Port are in two sets, separated by just a week. In that extra week many seed pods have developed.

No relation to : the escaping garden plant  Crown Daisy [aka Garland Chrysanthemum] (Glebionis coronaria) or  Golden Crownbeard (Verbesina encelioides) another escaping garden plant from the Daisy Family (asteraceae) [plants with similar names].

Not a true Vetch, for it lacks the tendrils at the end of the pinnate leaves characteristic of vetches. It is party-coloured meaning that it exhibits more than one colour at a time, and also, those colours themselves can vary. It is a herbaceous perennial which can display purple, violet, pink or white coloured flowers and their intermediate shades. An introduced-naturalised plant now found scattered about England and much less so Eire in grassy or waste places. The only other plant in the Securigera Genus hasn't been seen since before 1987 and then only in Cornwall.

A NITROPROPANOYL GLUCOSIDE

The leaves contain the bitter and toxic cardiac glucoside Coronillin, a Tri-nitropropanyl glucoside (being 1,2,6-tri(3-nitropropanoyl)-α-d-glucopyranose), which initiates arrhythmia and can be fatal, usually to cattle who may eat it. It is highly unusual in that it contains three nitropropanoyl moieties shown in black; the glucosidic moiety is show in red. It is well known that Fabaceae (otherwise known as legumes) can fix atmospheric nitrogen with the help of nitrogen-fixing bacteria to be found within the nodules on its roots, and this plant must be using some of that nitrogen in producing this nitrogenous compound. It is not an alkaloid because the nitrogen atoms are exocyclic rather than endocyclic.


This aliphatic nitro-compound is toxic to non-ruminant animals (including humans) causing slow growth, paralysis or even death, but is non-toxic to ruminants, such as cattle goats and sheep, which have a secondary combustion chamber:-). But it does play an important role in attracting pollinators and in repelling herbivores and micro-organisms. Nitro compounds may play a role in helping plants which are growing under stressed environmental conditions.


  Securigera varia  ⇐ Global Aspect ⇒ Fabaceae  

Distribution
 family8Pea family8Fabaceae

 BSBI maps
genus8Securigera
Securigera
(Crown Vetch)

CROWN VETCH

Securigera varia

Pea Family [Fabaceae]