Cirsium vulgare (bull thistle, spear thistle,Ā common thistle, cotton thistle)
When most people hear the word thistle, they think of the Scotch thistle (Onopordum acanthium) but there are 16 genera of thistles in the daisy/sunflower family Asteraceae alone. One of these genera, Cirsium, has at least 200 species with about sixty of them native to North America. Native thistles are beneficial to the environment but they are easily out-competed by invasive species. Just to be confusing, Scotch thistle grows throughout Europe and western Asia but it is not native to the British Isles. It's actually this species, Cirsium vulgare, that is Scotland's national flower.
We call this a bull thistle where I live but, like the Scotch thistle, it's a major agricultural pest. This scrawny specimen is growing in a crack in the sidewalk but it really doesn't do a healthy bull thistle justice. This species gets a lot bigger, with multiple arms and very prickly leaves. No grazing animal will eat it and it can completely take over a fallow field in a couple of years. Noxious weed control companies say serious bull thistle infestations can't be totally eradicated, only controlled. They recommend herbicides and yearly deep-plowing, so that (hopefully) it only grows on the margin of a field. I understand the farmer's point of view but, you must admit, Cirsium vulgare does have a very pretty, purple flower.
tangentwithtanner
germansingergirl
amandla
areudirty
titsay
