Norma Briggs wrote:
I have considered doing this:
1. setting the lawnmower on stealth mode to cut the grass to the quick.
2. laying a thick layer of card board on top of the former grass
3. putting the grass clippings on top of the cardboard
4. maybe some plastic sheets, anchored down on top of all that and just
going away for a few months to let it all decompose and the rest of the
grass die
5. and because of the ascetics, maybe putting some kind of more attractive
mulch down on top of the plastic.

I've done two things to clear heavy grass for a garden. Once I laid
down newspaper, a few sheets thick and covered that with mulch. The
following spring I just tilled the mulch and rotted paper into the
ground. It worked quite well.

Last year I did a much larger area (40 x 50) by laying a heavy plastic
sheet on the ground. My father was clearing an area 20 x 100 the same
day and we both happened to decide on the same method. He chose black
plastic, I went with clear. Both worked about the same except where
water collected in mine I had to punch holes. The clear plastic works
by letting the sunlight shine through and heating the ground and traping
the heat in. It gets quite warm and kills the grass completely, except
where collected water keeps it cooler. The black plastic heats up and
that heat is transferred to the soil. Water on the plastic doesn't
matter as much because the plants are also cut off from light. The big
difference, really, was that the clear plastic couldn't take the UV and
broke apart. I've got lots of shreaded plastic while his black plastic
was good enough for a second spot. On the other hand, I think the clear
plastic heats the soil to a higher temperature and kills more weed
seeds. We both had weeds but I had fewer. So, either will work well.
In the spring, we just pulled up the sheets and tilled the dead grass in.

--
Henry