On Fri, 27 Jun 2014 16:10:37 -0800, "Guv Bob"
wrote:

"David E. Ross" wrote in message ...
On 6/27/2014 2:47 PM, Guv Bob wrote:
"Brooklyn1" wrote in message ...
Guv Bob wrote:

How's a good way to break up hard soil? Since it's all level, my
first thought is to soak it good for a couple of days. I wonder if
renting an aerator might also be good.

An aerator won't do much on hard-pack adobe like soil except break the
aerator... aerators only poke holes, some extract plugs, but they are
meant for reasonably soft soil that may be slightly compacted from
foot traffic.

Most of the soil is fairly easy to dig down 2-3 inches, but about 1/4
of the back yard is bare & hard as a rock. When I was taking soil
samples, I had to use a pick to get down that far. But the whole
yard is dry and hard deeper than 3-4 inches.

That kind of soil won't let you grow much, let alone a lawn. First
where are you located? Geographical location plays a large part in
soil conditions. In many parts of the US southwest the soil is indeed
like cured concrete, breaking it up will will only result in it going
back to hard after the first couple of heavy rains... then the best
tack to take is to haul in lots of good top soil and do your planting
in that... it would cost too much to amend the type of soil you
describe and it won't be long any organic amendment will decompose
like it was never there.


Thanks. So Cal. According to a county site report for a shopping
center in the area, it has a base of older alluvial interbedded silty
clay and clay, overlain by interlayered sandy gravel and silty clay.


Thus, you likely have enough clay that gypsum would be appropriate.

The charts say all the grasses I have required 6-7pH. Soil is 6.5-7.0 more or less. I thought gypsum would make it alkaline.


Gypsom is a crap shoot for loosening compacted soil regardless but for
certain it will make your soil extremely alkaline and once there will
be near impossible to remediate. Were it me I'd break up the existing
soil as best I can and then find a source for good top soil and
calculate how many cubic yards to put in a six inch depth. I'd be
sure to place landscaping blocks at the down hill perimeters to retain
your topsoil in heavy downpours... it doesn't rain often in So Cal but
when it does it could easily be a deluge that washes away soil, and
that's why the soil there is so **** poor. I lived in So Cal for
several years, I know of what I speak. I had a Greek neighbor when I
lived in Pasadena who would instruct all his visitors to bring as much
top soil as they could from his home state of Ohio for his fig and
olive trees. Where I live now (in the Hudson River valley) I have
some of the best top soil on the planet, I can dig down six feet and
still be into rich black earth.