I had a load of top soil I never used last year next to my run and all of that started growing in it. Looks like it only propagates via seed so it must’ve been in the soil to begin with. Great.
Although from what I’m reading it is easy to win the battle with if and when I ever want to. It’s a legume like clover so it’s a nitrogen fixer. I was just really surprised how much the chickens loved it when they tried it. Their reaction may be neck and neck number 1 with plantain on the weed list.