Over the past months 8 trash bags of Tall Fleabane flower / seed heads removed from an area of approx 10 ha; mapped with Field Maps; photo taken yesterday night of one of the last remaining Tall Fleabane before being pulled out - still a few more to go.
It looks as though you have got it before the seed has dispersed, but it seems as though you didn't have a major infestation like some places. It is an annual that likes a bit of rain so you might not have so much next year; I wonder which weed will replace it.