Wane Smooth writes
It happens that Wane Smooth formulated :
Hi all.My lawn in covered with weeds.Amongst them are a lot of one
type that the goldfinches come to eat regularly.
At first glance it looks like a young dandelion (there are a lot of
those)but the surface of the leaf and the spine underneath are
covered in sharp spines.
Any ideas on what this weed is,thanks.

OK, think I got it.
Anchusa arvensis.
Thanks for the replies.

I'd be very surprised - it's a plant of bare sandy places rather than
lawns.
--
Kay