Dwayne wrote:
"Martin Brown" wrote in message
...

What colour is the flower and what does it look like?

I have not let it get that far, been ripping it out daily.

Flowers make the ID much easier.

A broadleaf specific lawn weedkiller will probably see it off.

Like the verdone suggested for that creeping buttercup?

Yes. Essentially it kills anything that isn't grass. You can even apply
it as a spot weeder if only small regions of the lawn are affected.

Autumn weed & feed mix will have the same effect. Typically the fastest
route to eradicating lawn weeds is a combination of digging them out and
treating them with Verdone or similar broadleaf specific weedkiller.

NB Be sure to wash out your weedkiller sprayer/can very carefully before
using with broadleaf specific mixture in it on a lawn. Grass is
exquisitely sensitive to glyphosate (which kills every green plant). You
must ensure the tank is clean with no residues left in it.

Regards,
Martin Brown