That is interesting dun, I let it head out for two main reasons, which was I want to go around and cut the heads of when they are mature and put them out on my back patio this fall and winter and watch all the birds feed on them and I wanted to create a good place for my grandson to shoot doves this fall. I think I succeeded. Maybe I created a monster, but, in a typical western Kansas year, I doubt it it gets to far out of bounds as far as coming up volunteer. As far as the cattle eating, they don't know any better I guess, cause they are eating it up, when they come to the taller stalks with heads on them I see them just kind of leaning the plant down and eating the leaves off the stem. They don't seem to be eating the head. That's for the birds.