[Terrapreta] char & vascular systems

[Kurt Treutlein]

Robert Klein wrote:
>  <<snipped>>
>
>  If the temperature goes very high, we may have a less usable product.
>  I learned that coked coal is very porous but also extremely hard and
>  tough.  This returns to the problem with the use of wood charcoal.
>  The wood does not naturally breakdown into a powder which is
>  preferred for soils.

<<snipped>>

Coke is certainly very hard and tough, as I remember from my much 
younger days when we fed it into a stove for room heating, but why is 
powdered charcoal the preferred form for use in soil? I have the 
impression that somewhere in the quarter inch lump size is considered 
good. ???

regards,

Kurt