It's obviously a daisy, possibly a Shasta daisy as they go a bit straggly. They need to be dug out completely if they're not wanted and get it done before they set seed or you will never get rid of them.

Agree with Cammomile.

I don't think its Shasta daisy - looks much more like Tanacetum, but its too tall to be the usual Tanacetum parthenium (feverfew). Could be one of the camomiles, but they usually have feathery leaves, and I can't see the leaves clearly in the picture. Shasta daisy wouldn't be popping up all over the garden either - Tanacetum and some camomile produce a lot of seeds which would explain why they're coming up all over. The trick, other than digging out the ones she doesn't want, is to deadhead before seed sets.

I would have said Feverfew. It does seed around. And it helps migraine - eat a leaf or two, in a small sandwich if you really can't bear the taste. But if it is that its a record height!

If you're going to get rid of it Hank it doesn't matter what you call it, how about Nuisance?

It might well be Leucanthemum vulgare, the oxeye daisy

The leaves don't look right for that, though its hard to see them properly.

Hank tell her what you like... and advise her to remove :)

I think it is feverfew (Tanacetum parthenium) and I certainly have had it almost 3 ft tall in the garden.