thistle

[cohan]

this plant is growing on my property in a fairly shady break in the woods, in an area that is mowed--it has been there for some years, usually getting mowed over--a half dozen rosettes, stretched in a line several metres long; i marked a couple of the rosettes to mow around the last couple of years, and this one rewarded me by flowering this year..
beyond what you can see in the pics, the rosette especially is fuzzy, both pale and purply, and prickles are rather soft--much more so than C arvense, for example, which is very common here; flowers are also much larger than C arvense, being 2-3 inches across (didn't measure  )
the local candidates seem to be:
1-Cirsium flodmanii- should have single heads at the end of several stems--this had 3 heads at the top of one stem' doesn't seem to have the purpliness
2-Cirsium hookerianum-- looks about right vegetatively, but should have white flowers, not pink-purple
3-C undulatum-wrong habitat and shouldn't be in my area; also single flower heads
4-C vulgare-uncommon weed- again, single flower heads, should be pricklier...

so--another species not listed in my book? (didn't find anything online..) or, a hybrid of the first two? colour variant of numb 2? whatever it is, it is not common in my area, haven't run into it anywhere else, but if it is in this sort of semi shady woodland, thats mostly private land and i wouldnt see it...
if i really dig, i might be able to find a shot of pre-flowering rosette....

[Maggi Young]

Smart thistle- though I can tell by its accent its not Scottish!

I'll be keen to hear what the Canadians reckon to the ID..... nice looking thistle an no mistake,

[cohan]

thanks, maggi i really like it, though i'm mostly wanting to know whether to encourage it (= native) or keep it in check (=foreign invasive) ..at least i know it didn't invade from scotland!
its just dropped a big blob of seeds (no blowing around, as our weather has been something scots might recognise--cold and wet!) and i have to pick them up for sharing and sowing in one case, disposal in the other!

[cohan]

i did find some better foliage shots from earlier in the season before the flower stem stretched out fully (btw, i think it was about 50cm tall, i could check if it matters...)

[Maggi Young]

My goodness, it just gets better, doesn't it? 

[cohan]

it is a cute fuzzy thing, isn't it

[cohan]

i went out and picked up the seed head--which was just  a damp dead flower, basically, and brought it inside..there it sat ignored for a while, until i went near the area and noticed a large mass of dry fluffy seeds, with wings extended ready to fly on the slightest breeze-luckily it isn't near the ceiling fan!
anyone want some seed, even though i still don't have a name?

[Lesley Cox]

Handsome is as handsome does and I suspect it could very easily become a major menace. If it's a Canadian native, you're very welcome to it Cohan. Please don't be sending any in this direction. We have more than enough to cope with already.

[cohan]

Handsome is as handsome does and I suspect it could very easily become a major menace. If it's a Canadian native, you're very welcome to it Cohan. Please don't be sending any in this direction. We have more than enough to cope with already.

lol--same could be said for a great many other plants--especially other asteraceae with fluffy seeds such as this.. this is why i wanted to collect the seeds until i know what it is!
i still haven't been able to pin it down, but the odd thing is that i have seen no others in my area (i certainly don't see all the land around, but obviously common plants crop up repeatedly, and our invasives-in the countryside-are all agricultural weeds, widespread around fields, roadsides and farmyards....)
our prevalent thistle --a very common and problematic weed-is Cirsium arvense-ironically called Canada thistle, when its a european invasive, like most of our problem weeds....

[Lesley Cox]

Cirsium arvense is the bane of my life too and I know it as Californian thistle though my mother always called it Canadian. Most unfair considering its origin.

[Stephenb]

Cirsium vulgare? Spear Thistle. Has yellow tipped spines, is downy - biennial... Leaves are deeply pinnately lobed - reckon I can see all those three features in your photos.

See also: http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=200023702

[cohan]

i'm not sure, stephen, that's what i was thinking before i started looking into it, and it may be; i don't know how variable the species is--mine just did not seem as prickly as those i see in photos, though, looking more online now, i see some immature rosettes that look more like mine than initially i thought...
the differences i see from images and descriptions:
-C vulgare is described as having longer stiffer spines than C arvense, my mystery thistle is softer than arvense, really just barely prickly, and hairier than most of the images i see of vulgare,including hairy stem (that seems to be variable?)
-C vulgare is said to have single flower heads per stem, whereas mine had a cluster of three;
-bracts on the flowerhead on mine seemed much less spiny than pics of vulgare and the bracted base of the flower head seems larger relative to the 'disc' than on my plant...
however, as i said, i don't know if these characters vary and this is just a variant vulgare, and/or if the several species of Cirsium in the broader region (only arvense is commonly seen here, and it's very common) hybridise??

[cohan]

Cirsium arvense is the bane of my life too and I know it as Californian thistle though my mother always called it Canadian. Most unfair considering its origin.

i like the idea of calling arvense 'california thistle' takes away the blame from us, and makes it seem like we have something more exotic growing here
in gardens here its unlikely to go away, but manageable enough... in some fields its a real problem...no weed bothers me like the d****d buttercup though (not in my garden, but in semi wild pastures etc)

[cohan]

having spent some time on north american efloras (in spite of not having live flowering plants in front of me to check some things, and not 100% certainty that i have understood some of the terms correctly...) i think Cirsium flodmanii is my best bet; i hesitated at this sp initially, because in my book it seemed yo have only single flower heads, and mine had 3; the eflora says heads borne singly or few, so i think it still is in the running..
http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=250066371

the dist map in royer and dickinson includes my area, and although described habitat in efloras sounded better for hookerianum, that species is less apt, in having sprouts from a taproot, whereas flodmanii has a horizontal runner root--my plant has a several rosettes spread out along a long line..
compared to photos online, my plant does seem chunkier, in spite of being in a rather shady spot, so perhaps its a variant, or a hybrid-the species notably hybridises with undulatum, which species also seems a pretty good match, though it should be farther south in drier environs....

it does not seem right for C vulgare, in particular looking at the base of the flower head of my plant (involucre; stop me if you catch me using any terms incorrectly  the bracts which comprise the exterior of the involucre-- phyllaries--  have a notable whitish ridge (as in flodmanii and hookerianum) a darker area below the ridge (flodmanii), and the spines at the tip of the phyllaries are abruptly (flodmanii) spreading (hookerianum) unlike in vulgare..
oddly, on my fairly extensive rides around the area, i have not seen a single other thistle other than arvense, though of course you would not see them in passing out of flower...

[Lori S.]

Cohan, I haven't pored over your photos and description in much detail, but I thought I'd just add the following...

-C vulgare is said to have single flower heads per stem, whereas mine had a cluster of three;

Flora of Alberta disagrees, and says of C. vulgare, "heads usually several".  

The F. of A. key also makes the following basic distinction between C. vulgare and the native species - "upper surface of leaves scabrous with appressed spines" (= C. vulgare); "upper surface of leaves not scabrous" (= the 6 native species).  From your photos, the upper leaf surfaces look scabrous (rough) but I may be misled...

I can't say I've studied thistles enough to help out particularly, other than to confirm that it is not C. hookerianum, which I do take note of and always enjoy seeing (see links for photos of it):  
http://nargs.org/smf/index.php?topic=131.30
http://nargs.org/smf/index.php?topic=361.0