Since my community is named after Airdrie, Scotland, and because the thistle is the national emblem of Scotland, I have attempted to grow bull thistle in my yard for several years to no avail. It's not that the plant isn't hardy, it is, but that my husband is tenacious with weeds and though I point out that this particular weed has been planted on purpose, he keeps forgetting until it's too late. I think the thistle is gorgeous, growing up to two meters in height.
The roots of this plant is edible when cooked and apparently is similar to Jerusalem artichoke in flavor and texture though more bland and so was often mixed with other vegetables. It has been dried and stored and the young flower stems cooked while the leaves were typically soaked overnight in salted water and thorns removed prior to being cooked and eaten. The flowers were often dried and used to curdle plant milks while the seeds were roasted and eaten.
The roots were also used as a poultice and a decoction on sore jaws. The entire plant was boiled into an herbal steam for treating rheumatic joints. The down was often dried and used as tinder.