On Fri, 18 Jul 2014 19:18:31 -0700, "David E. Ross"
wrote:

Spike aerators do more damage than they correct. They compact the soil
around the holes they create.

Plugging aerators loosen the soil by removing plugs. Where the soil is
heavy clay, this can be a great benefit. The holes permit water to
penetrate the surface, carrying nutrients towards roots. Believe it or
not, roots also benefit from the increase in oxygen reaching them.
Spike aerators prevent all this instead of permitting it.

Aeration can be important wherever there is foot traffic across a
planted area.

"Plugging" aerators also remove thatch in the lawn turf at the same
time (two birds - one stone).

Here in the desert, we live on "hard pan" / compacted soil. Much of
the reason we have flash floods from water not soaking into the
ground. Dust is like talc powder.

Gypsum is used to break down the difficult soil - reducing compaction.
Many home gardens are in raised beads vs fighting the soil without a
back-hoe.

Golf course greens are aerated or thatched.