This weed is spreading on my lawn. What is it and how do I get rid of it organically please? Right now I just pull them by hand

Spotted Spurge.

Thanks

There is no organic method except covering the area with several inches of mulch.
If you can pulling it works best BUT it has a deep root and if you do not get the whole root it will come back.
I try to pull when the ground is quite moist.
At that you pull it and then put down a pre-emergent in spring.
Do this for several years and it will be easy to control if not gone.

@RpR There's a catch 22. If I put down mulch then the grass won't be able to grow. What is a pre-emergent?

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