permaculture

[Dieter Brand <diebrand@yahoo.com>]

-- On Mon, 11/14/11, John D'hondt <dhondt@eircom.net> wrote:
> It is almost impossible to find out afterwards whether broccoli 
> heads or rice bran was used in humus production.
> In contrast, when animal manures are included it is still
> possible even after a hundred years (and often much more) to 
> determine exactly which animal contributed to the fertility.

Do you have any reference for this?

Dieter