Greensand and other mineral sources

Andrew Ashley <aeashley@stlnet.com> wrote about Greensand...

> Subject: Spend money on something else

> Finally something came alond to get me to type!  Green sand is
> worthless; so don't spend any money on it.  Even if it is not your own
> hard earned money.  What does Green sand contain?  Fine.  Is it
> soluable?  Will the nutrients be available to your crops?  NO!  I think
> not, not in this lifetime anyway.  Rock powder, granite dust, green
> sand; these don't cut it.

I would agree that in the test-tube, solubility of minerals from 
some of these mineral sources might be low. However, over a year 
or more, with microorganism activity on the surface of grains 
producing micro-local pH variations and other micro-local 
chemistry such as oxidizing and reducing conditions, all of which 
could contribute to the solution of minerals, I couldn't be as 

Soil mineral levels are not just the sum of thousands or 
millions of years of slow solution - rainfall would prevent
the build up of any significant levels by washing them into 
streams, rivers and the sea. That we do have fertile soils 
means that the process of solubilization is continuous.

The point about adding 'sustainable type' minerals is that their 
release of minerals IS slow.

The important questions are: how effective the different mineral 
improvers / suppliers, and what are the soil conditions that 
affect mineral release. These could/should be (and may even 
already have been) addressed by some 'hard' (i.e. good) science!

Bob Hare
(Dr W.R.Hare     rhare@gn.apc.org)