FEVERFEW : Tanacetum parthenium
If this looks like a daisy to you, that is because it is from the same family. It is an introduced plant, but so long ago that it is now considered native. UK Wildllowers says : Tanacetum parthenium is an Archeophyte (introduced before 1500 AD) which has been in the British Isles long enough to establish itself as well as many native plants. It is common in England and Wales and in Scotland is only scarce in the far north west. This fairly common plant is an introduction from the Balkans but has been used for centuries to cure arthritis, headaches and now is suggested as a herbal cure for migraine sufferers.
This example is in a private garden in late June, but it has also been identified in more natural environments.
WIKIPEDIA : https://en.wikipedia.org/wiki/Tanacetum_parthenium