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CREEPING THISTLE

Cirsium arvense

Daisy & Dandelion Family [Asteraceae]  

Flowers:
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Pappus: pappusZpossible (white, simple)
pappus8aug pappus8sep pappus8sept pappus8oct pappus8nov

status
statusZnative
 
flower
flower8lilac
 
morph
morph8actino
 
petals
petalsZmany
 
stem
stem8round
 
stem
stem8winged
 
stem
stem8spines stem8thorns
prickles
smell
smell8fragrant
fragrant
contact
contactZlowish
 

1st Aug 2007, Belmont, Lancs. Photo: © RWD
Spreads by long, creeping, underground rhizomes. The bane of farmers; once it's in a field, it is hard to eliminate.


19th July 2005, nr Haddon Hall, Derbyshire. Photo: © RWD
The only other (?) Thistle with lilac-coloured florets is Slender Thistle, which is distinctively short, with a smaller flowerhead and flowerheads bunched together, is little-branched and grows near the sea.


2nd Aug 2005, Leeds & L/pool Canal, Parbold, Lancs. Photo: © RWD
Grows from 20 - 120cm high (2m max).


27th June 2015, Knowsley Safari Park. Photo: © RWD
Flowers yet to elongate and open.


27th June 2015, Knowsley Safari Park. Photo: © RWD
Elongated. Still not yet open. Leaves bright-green, narrow but strongly warped by differential growth, especially where the spines are.


27th June 2015, Knowsley Safari Park. Photo: © RWD
It is well-branched. Spines very sharp!


8th July 2017, Ind Est waste ground, Ellesmere Port, Cheshire. Photo: © RWD
This specimen looks similar to Melancholy Thistle with the much paler flower-stalks,, but it is well-branched and Creeping Thistle does not hybridise with that.


8th Aug 2007, Rochdale Canal, Hebden Bridge. Photo: © RWD
A more stereotypical example with flowers at ends of long branches. Flowerheads open, displaying florets which are splaying outwards and downwards rather like some current politicians hair mops...


8th July 2017, Ind Est waste ground, Ellesmere Port, Cheshire. Photo: © RWD
Flowerheads in various stages from un-opened to seeding with their distinctive narrowish but tapering body surrounded by many short purple phyllaries. Stems slightly ribbed. The flowerhead is a narrow 8-20mm diameter, longer than wide (when fully grown). Corolla about 15mm long.


10th Aug 2012, a moorland road, nr. Flagg, Derbyshire. Photo: © RWD
The purple phyllaries, curved out at the end. Typical shaving-brush appearance when the seed head begins to emerge from the discarded flower parts (some of which lie on top of the brush - these are not seeds).


8th July 2017, Ind Est waste ground, Ellesmere Port, Cheshire. Photo: © RWD
Shaving brush and phyllaries, the centre-line of which bulges slightly and is a deeper reddish-purple. White hairs lie flat on the flower-stalk near the head.


8th July 2017, Ind Est waste ground, Ellesmere Port, Cheshire. Photo: © RWD
Albino versions of Creeping Thistle lack any purple colouration - the inflorescence is white, the stems are not flushed purple, nor are the phyllaries, they are just revealing their underlying colour: green for the phyllaries with a white raised midrib, and very pale-green flower-stalk.


8th July 2017, Ind Est waste ground, Ellesmere Port, Cheshire. Photo: © RWD
Albino version phyllaries of un-opened flowerhead.


31st July 2007, Photo: © RWD
A candleabra of seeding flowerheads with parachuted seeds escaping from some.


8th Aug 2007, Rochdale Canal, Hebden Bridge. Photo: © RWD
The seeds expand so much as to make the phyllary cage expand, some parachutes are now escaping with their carge of one seed each.


8th Aug 2007, Rochdale Canal, Hebden Bridge. Photo: © RWD
The extraneous detritus on the pallus are discarded florets.


8th Aug 2007, Rochdale Canal, Hebden Bridge. Photo: © RWD
In the very centre is a simple parachute with a seed directly below. The long thin thing sticking upwards with a thicker end is not the seed but rather the old decaying female floret. The seed is hidden immediately below it.


31st July 2007, Arnside, Lancs. Photo: © RWD
Leaves 8-20cm long, with at the least the basal leaves cobwebby underneath, strongly warped by their growing spines.


27th June 2015, Knowsley Safari Park. Photo: © RWD
The pale-straw coloured spines. Your Author calls them Sid for they are very Vicious :-)




A REDDER ANOMALY

14th Oct 2009, Deepdale Lane, near Dent, Yorks Dales. Photo: © RWD
A very atypical specimen. Your Author thought this was the hybrid between Creeping Thistle and Marsh Thistle, but apparently it is still Creeping Thistle, albeit a very eccentric example. Not only are many of the leaves suffused with red making them darker-green than usual (however there are some paler-green normal-coloured ones) but the leaves are both much longer and wider than is normal. Moreover, the inflorescence is infused with this same reddish-purple colouration over-powering any lilac tinge.

Your Author supposes this is a mirror to the albino version; where that lacks any lilac or reddish-purple colouration on inflorescence or phyllaries, this example seems to have a double-dose.

But not only that, the leaves are much longer and wider and seem not to be so shiny, but rather have a matte finish suggestive of being covered in very short fine hairs appressed to the surface. And, despite Clive Stace specifying that Creeping Thistle lacks wings going down the stem this specimen does have a (short) wing (half-way down on the left, just at the start of the rock). Marsh Thistle also has winged stems. (However, another reliable source tells me that even Creeping Thistle can have some winging on the stems). And, to cap it all, this was a lone example; it was not spreading as its name suggests it should...

However, Marsh Thistle has a very crowded and compact top with many inflorescences crowded together, whereas this exhibit has the normal few and separated florets of Creeping Thistle (and is not intermediate between Creeping and Marsh Thistles). Apart from the large size increase, the leaves are also a similar shape, if not as shiny.

So, the consensus is that this particular specimen is not a hybrid, but rather just Creeping Thistle, albeit, a very unusual one suffused with red in parts that are normally devoid of red, which is just one of the characteristics of the real hybrid between the two - the other identifying characteristics being absent. The real hybrid is also very rare).





A BACTERIAL DISEASE

PSEUDOMONAS SYRINGIAE (A bacterium)
OR
PHOMA MACROSTEMA (A Rust)
 Galls and Rusts Menu

4th Oct 2009, Bouldnor, IoW. Photo: (CC by 2.0) Mike Cotterill
It has been noticed by several botanists down south that in the last few years since about 2008 Creeping Thistle has sometimes been bleached near the top. It was at first thought this was just due to lack of chlorophyll as can sometimes occur in many species of plants. But when it was investigated more thoroughly it was found, in one instance, thought to be due to a bacterial infection called Pseudomonas syringae (a bacterial infection is highly unusual for any plant). This would be a new pathogen.

Pseudomonas syringae infection has been confirmed in the Isle of Wight, which is where these photos were taken. It has also been found in several other places such as near the coasts of Sussex, Anglesea and Pembrokeshire). It seems to have a preference for coasts. But no one knows how the bacteria arrived in the UK, although your Author can think of many ways in which it could have arrived here. It has been found in several locations in Canada. The symptoms are visibly very characteristic of the disease and it can be readily observed in Creeping Thistle from some distance.

On another occasion and on other specimens, an infected Creeping Thistle was found to be caused by a differing organism, that of Phoma macrostoma (which is not a bacterium as is Pseudomonas syringae) but rather a soil fungus aka a rust. It is therefore a bit of a surprise that both exhibit exactly the same visible results. And both are being studied as potential 'green' biological control agents for Creeping Thistle, particularly in farmers fields where it creeps by means of underground runners, thereby invading fields. Phoma macrostoma kills Creeping Thistle by infecting the root system and then releasing a phytotoxin produced in the plant. This organism is not specific to Creeping Thistle, and infects many dicotyledons, such as Clovers, Lentils, and other broad-leaf plants, but monocots are very resistant. In light of this, your Author thinks Phoma macrostoma is not nearly as selective as is Pseudomonas syringae and that they would be better off not promoting this organism as a control agent for Creeping Thistle (or any other dicot).

But the Creeping Thistles above were found in the Isle of Wight and thus have Pseudomonas syringae.



4th Oct 2009, Bouldnor, IoW. Photo: (CC by 2.0) Mike Cotterill
Above specimens, magnified.


Not to be confused with : Creeping Bent, Creeping Raspwort, Creeping Jenny, Creeping Cinquefoil, Creeping Buttercup, Creeping Yellow-Cress, Creeping Willow, Creeping Comfrey [plants with similar names belonging to differing families]

Hybridizes with : Marsh Thistle, Dwarf Thistle and Melancholy Thistle, the latter might not have been seen for yonks and the others only rarely occur in certain few places.

Some similarities to : Slender Thistle (Carduus tenuiflorus which has shorter and narrower flowerheads on very short stalks in dense clusters at the summit, is usually shorter (15-60mm) - see captions for other differences or look-see yourself :-)

Uniquely identifiable characteristics

Distinguishing Feature : Usually lilac coloured florets (but occasionally white or red)


  Cirsium arvense  ⇐ Global Aspect ⇒ Asteraceae  

Distribution
family8Daisy family8Dandelion  family8Asteraceae

 BSBI maps
genus8Cirsium
Cirsium
(Thistles)

CREEPING THISTLE

Cirsium arvense

Daisy & Dandelion Family [Asteraceae]  

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