permaculture

[Allan Balliett <aballiett@frontiernet.net>]

>  How does this compare to applying charcoal (a la terra preta) ?
>  Presumably TP is both safe and sustainable to soil biota, as they
 were doing it for years and ended up with good soil.<SNIP!>

Charcoal is produced at a lower heat than ash is. The charcoal 
(rather than ash) that is produced by lower heat has a lot of porous 
structure to it and, apparently, is coated with a carbon that is a 
sugar food for microbes. In this fashion, charcoal both feeds and 
shelters a microbial population. Ash just doesn't do that. Even 
better, charcoal-wise, charcoal has remained an effective soil 
builder in pt soils for up to 2000 years (actually documented) while 
ash is consumed in just a few months. Still, my soil science friends 
tell me that FRESH ash contributed more to the performance of plants 
than can be predicted by a lab analysis of the ingredients of ash. 
-Allan