Will turning grass over kill it, or should I go to the trouble of...

[FluffyJumper]

shaking the garden fork and bashing the lump of earth about to separate the plant matter?

It's only grass that's about a year old so not going to put up some kind of mad triffid like fight.

Lovely first day of the gardening year here .

I just cut it out in squares and turn it over! That's always worked for me.

Turning it may not kill it unless it's dry for a while.