Although the center "puff" of the flowers looks a bit yellow in the photo, they were all white when I picked it. I had thought chamomile, but again, the centers are white.

It is Tanacetum parthenium IMO. There are double flowered versions which are virtually all white. Are the leaves yellow or is that just the light?

I put it in water then forgot to take a picture until it was starting to dry out, so I hope it is still identifiable.

==>> that is why the leaves are yellow ...

otherwise its green right. raeee??

ken

I asked, Ken, because there are cultivars with yellow/chartreuse leaves. If this one is both double flowered and chartreuse-leaved I would not be pulling out the seedlings.

Thank you floral_uk and Ken. Yes, the leaves are yellowed both because we had already had some frosts, and because it was a few days before I snapped the pictures. You can see their normal green in the shot with the blossoms.

I hadn't thought feverfew was a wildflower here; I wonder how or why it sprouted so abundantly all over my yard this summer! Would you let it (some of it) grow next spring instead of pulling it?

I did find some photos of the double, all white variety of feverfew (except for a little spot of yellow in the center), but those blossoms don't seem to have the longer, slightly droopy outer petals. Of course with the sample withering in the photo now I can't quite recall how it looked when fresh.

Feverfew isn't a wild flower unless you live in South Eastern Europe/Eurasia, but it has been so wildely cultivated that it has spread around the world. It pops up on my allotment and, unless I need the space for something else, I leave it be. It's very tough, quite pretty and is a medicinal herb.

Me too, Floral. Same with ox-eye daisies and anthemis.