Weed id

[Palustris]

Not alpine I know, but we need an id on this nasty little interloper in the Bowling green
Not seen it flower. Persistent roots, any bits left soon regrow. Rampant thing and seems resistant to broad leaf weed killer.

T.i.a.

[Tomte]

The first photo makes me hesitant due to the more or less entire leafs, but the second one strongly reminds me of ragwort (Senecio jacobaea). Possibly younger stages of this plant may also have more entire leafs, and from personal experience this also fits your description in terms of persistence.. nice flowers, but better not touch it ungloved, it’s liver-toxic upon skin contact.

[Palustris]

Thanks. Book says that Senecio jacobaeia does not have runners and this thing most definitely does. Obviously it is not a weed either myself or the greenkeeper have come across before. One suggestion is Glechoma?

[Tomte]

Surely not glechoma.. the habit is very different. Senecio erucofolia has runnets, but has even more pinnate leaves. Can’t really tell from your pictures if that would match.

[Vinny 123]

It is doing an amazingly good impression of ragwort if it isn't ragwort.

Have you carefully extracted more than one and definitely found one to be connected to the other?

[Palustris]

Greenkeeper says that it grows to about 18ins tall if left alone and that the flowers are definitely not yellow, so maybe not Senecio.
Had a look at the rear of the leaves and they are not hairy.
He has potted some up and we will grow it on to flowering to see if that helps.
Thanks all the same.