Reminds of when I was a kid. The neighbor visited cousins in Canada one summer. Came back with some plants with “pretty purple flowers”. Within six years we couldn’t kill Canadian thistle out of the pasture...... >PS
As we tell visitors in Florida, take nothing but pictures, leave nothing but footprints.......
I read that its leaves, root and stem are edible, after de-spining. Tedious, but edible. Its good to know what is edible when times get apocalyptic......