Dave wrote:

Mulching your lawn is good practice during a drought season

I don't buy the mulching argument.

In my experience, mulched grass creates a sponge layer at the surface
and any rain that comes in the summer (we're having a drought, like we
usually seem to do every summer, here in SW-Ontario).

When we get our pathetic quick thunder storms, the rain rolls quickly
off our hard-packed clay soils. Any rain that doesn't run off gets
absorbed by the dried mulch layer, which then gives it back to the
atmosphere when it dries. It prevents the moisture from reaching and
being absorbed into the soil surface.

You might say "well, just add better top soil to your lawn". That
doesn't work if we're talking about city-owned portion of your front
yard, or the grass circle in the middle of a court.

It is universally said that mulched grass contains nutients that are
great to give back to your lawn.

Well, if cut grass was so great, then why don't municiple yards that
collect yard waste accept it? These places take yard waste (tree
branches mostly, maybe pine needles and other stuff you rake) and
mulch/compost it and sell it. But they won't take grass. Why not I
ask? Everyone says that grass contains all these nutrients? Grass
should be great, perfect to add to the ground-up yard waste? But no,
they don't take it. If they take it, they charge you $1 a bag.

The truth is that municiple garbage collection and yard-waste
management knows that cut grass is useless and nutrient-poor (full of
carbon mostly) so they create this con-job and tell people it's better
for your lawn to mulch. They just don't want to deal with cut grass
so they want you to just leave it in your grass, where it will create
thatch that will thin out your grass, harbor bugs and disease and soak
up the little, precious water you get in the summer and act like a
barrier to prevent the water from getting to the parched soil
underneath.