Galinsoga parviflora Gallant Soldier C DD I
This South American introduction used to be a weed of the South of England. When I started botanising in the 70s this was rarely found at all in the North West of the country. Now it is fairly common and I have it as an occasional weed in my herbaceous border. This particular plant was all over an arable field in the Channel Islands where it is quite common, as you would expect.
G. parviflora has naturalised itself well in central, southern and eastern England but not so well in the west and in Wales. It has hardly established a presence in Scotland and is very rare in Ireland.