I've been advised not to let these proliferate on the property. I ignore this advice, happy to see them sprout, grow tall and begin blooming. They've also helped me survive when I needed green food and had no money to buy some at the supermarket. Bull thistle stem core sautéed in a little olive oil and chili paste, mmm mmm mmm mmm mmm!
And when they are in full bloom, Sphinx Moths arrive to feed from them.
As do Swallowtail Butterflies
A fine plant to have around, just not very hug-worthy.