this is a lab I teach in my course. go down to soil composition.
http://weloveteaching.com/spring2008...ock-cycle.html
lots of good info in the other messages. Ingrid

On Wed, 27 Feb 2008 17:23:34 -0800, "Eigenvector" wrote:

I was thinking about this as I dug up the winter weeds in my garden. My
soil is riddled with rocks, rocks of various shapes, sizes, and
construction. Nothing too obnoxious, I rid myself of the boulders long ago,
but kept the walnut sized ones.

But I was thinking, I wonder how important those rocks are to my garden. Do
the flowers and herbs use them to anchor themselves to the ground, do the
rocks give off the important minerals that the plant needs or does the soil
alone supply that, without surface rocks will the spiders have less places
to live. Do the rocks provide that last shred of moisture to the roots
during dry times

Question, for those who have done this for a long long time, do you find
that soil that is essentially just dirt that plants grow better or worse
than in soil that is natural and rocky but still of good quality?