Stop the killing!
That's prunella, or self-heal, and we should all have some in our lawns (I do).
It has both diuretic and antibacterial components; Chinese use it for high blood pressure, among other things and it makes a great poultice for minor wounds...
When did we get so anal about lawns It's not natural or healthy (mentally or for the environment

) Old English lawns had bellis, crocus, and all sorts of flowers in them.
Then Scotts wanted to sell more fertilizer and told us anything that wasn't grass was a weed. It' working great for them and BAD for us, and the environment around us.
I like (and use) my prunella; what can your lawn heal?
Scott