Appreciation: Ornamental Cirsium planting in Stanley Park

I think this is Cirsium vulgare, but feel free to correct me [edited - I was corrected, see below; it's Cirsium arvense]. I found it slightly creepy to have so many of these thorny things packed into one area, just east of Stanley Park Drive at Ceperley Meadow. At least there was a sort of path alongside them to get a good look at them. It's possible that they weren't planted, but I don't remember seeing them like this before, and it's the only area where they are so densely packed in.

 

A patch of Creeping Thistle, native for me, an invasive weed for you. It forms large clonal colonies like this by sprouting from its creeping root system (hence the name); very unlikely to have been planted deliberately!

 

Oh, Cirsium arvense. Thanks, Michael. Is that wider leaves than C. vulgare?
I was thinking this morning, maybe it's really all over that meadow and the Parks Board mows down the rest, decided to leave one patch.

 

Yep, wider leaves, with only relatively short spines, and also smaller flowerheads. Here's a Spear Thistle for comparison: File:Cirsium vulgare Harthope.jpg - Wikimedia Commons - note also that it forms single plants, not clonal colonies.

Possibly part-mown, but it may just be that the area occupied is just how far the clonal colony has spread since it started.

Over here, Creeping Thistle is a good wildlife plant, excellent nectar source for bees, the leaves good food for Painted Lady butterflies, and the seeds good for Goldfinches. But I guess you really don't want it in Vancouver. It won't be easy to get rid of, though!

 

I see that another identifying feature of C. arvense is that it has separate male and female plants, with a few flowers showing up on the "wrong" plant. Finally on page 7 of google I have found a page that clearly identifies which flower is which, with several photos too, though it's a pdf so you can't expand the images. The other pages do mostly all say that the male flower shape is more rounded.
http://www.naturemanitoba.ca/sites/default/files/CanThistle.pdf

I found a good video that describes the identifying characteristics of the plant. From University of Wisconsin Extension.