Daisy & Dandelion Family [Asteraceae] |
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4th July 2006, Bohemia Corner, Ventnor, IoW. | Photo: (CC by 2.0) Geoff Toone |
A neophyte which is often found as a garden escapee and growing erect to 2.5m, much taller than the field full of Stinging Nettles surrounding it. Both leaves and stems are greyish-white with masses of appressed hairs, paler green where the hairs are fewer. It is branched. |
4th July 2006, Bohemia Corner, Ventnor, IoW. | Photo: (CC by 2.0) Geoff Toone |
This specimen is wilting somewhat - the brush-like infloresence having turned pale-brown and some leaves also. |
4th July 2006, Bohemia Corner, Ventnor, IoW. | Photo: (CC by 2.0) Geoff Toone |
The stems have broad spiny wings along most of their length and a few long spiny leaves (10-50cm) which are similarly silvery-grey. |
4th July 2006, Bohemia Corner, Ventnor, IoW. | Photo: (CC by 2.0) Geoff Toone |
4th July 2006, Bohemia Corner, Ventnor, IoW. | Photo: (CC by 2.0) Geoff Toone |
The flowers are solitary atop each branch. |
4th July 2006, Bohemia Corner, Ventnor, IoW. | Photo: (CC by 2.0) Geoff Toone |
The flowerheads are large, 20-60mm wide and very spiny. The greyish-white hairs covering the wings (and the leaves) are all laid flat and almost parallel as if combed from stem to the tips of the spines. |
4th July 2006, Bohemia Corner, Ventnor, IoW. | Photo: (CC by 2.0) Geoff Toone |
The flowerheads, like those of Woolly Thistle, are 'cobwebbed' in grey-white hairs between each neighbouring spine, but are not as spherical, being more oblate spheroidal in shape, shorter than wide (not counting the purple florets atop). |
4th July 2006, Bohemia Corner, Ventnor, IoW. | Photo: (CC by 2.0) Geoff Toone |
The brush-like inflorescence seems little different to all the other thistles, apart from both size and colour (in the case of Creeping Thistle with its lilac-coloured inflorescence). It has disc florets with 5 long and narrow petals each, surrounding a single white to indigo-coloured style. |
4th July 2006, Bohemia Corner, Ventnor, IoW. | Photo: (CC by 2.0) Geoff Toone |
The style is often indigo coloured and protrudes out of the purple disc-floret 'petals'. |
4th July 2006, Bohemia Corner, Ventnor, IoW. | Photo: (CC by 2.0) Geoff Toone |
White pollen grains. |
4th July 2006, Bohemia Corner, Ventnor, IoW. | Photo: (CC by 2.0) Geoff Toone |
The interconnecting mesh of hairs between each sharp spine - like the wiring of an old telephone exchange. Spines turning fawn-coloured at their tips. |
4th July 2006, Bohemia Corner, Ventnor, IoW. | Photo: (CC by 2.0) Geoff Toone |
Your Author surmises that the web of cottony threads between the wiry green bracts on the flower head forms akin to the way drying Evoslurp™ glue dries: with a semi-viscous liquid between them at first, then, as the bracts grow and part from each other, the liquid is stretched whereupon the surface tension dictates that it forms threads between parting bracts, which then either dries, polymerises or oxidises into the threads seen, much as does Evoslurp™ glue when two recently coated surfaces are parted. It is possible the spiny bracts themselves exude the semi-liquid viscous fluid when they are all touching each other. The Author does not know if his theory is correct, but it seems logical Captain Kirk™. Spear Thistles, Woolly Thistle, Globe-Thistles and Cobweb Houseleeks also have networks of woolly threads between an array of bracts. |
4th July 2006, Bohemia Corner, Ventnor, IoW. | Photo: (CC by 2.0) Geoff Toone |
The wings on the stems are broad, but not continous as some books say.the spines can be seen to extend from the stem all the way to their very sharp point through the wing. |
4th July 2006, Bohemia Corner, Ventnor, IoW. | Photo: (CC by 2.0) Geoff Toone |
It seems plausible that the viscous stringy fluid theory also applies to the hairs on the wings: they seem to stretch along the direction in which the wing grows, so all end up parallel to each other. |
Photo: (CC by 2.0) Geoff Toone |
The basal leaves; stem not yet grown. |
Photo: (CC by 2.0) Geoff Toone |
Photo: (CC by 2.0) Geoff Toone |
Basal leaves. |
Easily mis-identified as : Woolly Thistle (Cirsium eriophorum) but that belongs in a differeing genus and differs from Cotton Thistle in the following ways:
Distinguishing Feature :
No relation to : Cottonweed (Achillea maritima), Common CottonGrass (Eriophorum angustifolium), It is a non-native plant which often escapes from gardens particularly in the South East of England; it is seldom found in the west of the UK, or north of Scarborough. Occupying field borders, verges, and waste and rough grounds especially on dry, sandy or chalky soils. It was naturalised or appeared casually since the 16th Century.
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Onopordum | acanthium | ⇐ Global Aspect ⇒ | Asteraceae |
Onopordum (Cotton Thistles) |
Daisy & Dandelion Family [Asteraceae] |