[Terrapreta] Charcoal agriculture: not ready for prime time

[rukurt at westnet.com.au]

Tom Miles wrote:
>
> My thought was more modest:  a concentration of charcoal left in a 
> poor soil from any natural cause could have resulted in abundant 
> growth and  inspired terra preta. Studies that I have linked on the 
> terra preta site have shown that the nutrient impact of fires in 
> grasslands only lasts for about a year, and slash and burn about three 
> years. Forest fires, however, can leave some substantial pockets of char.
>
>  
>
> Tom
>
>   
>
Nutrient impacts of fires are most likely due to the ash and not the 
charcoal, which is mainly left on the surface anyhow.
I believe that for maximum impact the char has to be ground somewhat and 
incorporated and possibly impregnated with other nutrients.

Kurt