wim

Wow, thank you for your answers!

Momoese,
If you went 4 feet down to mix organic mather in your soil, how do you do that practically? 1 foot deep that's a tree spade deep, 2 feet down is more dificult, but not impossible, but 4 feet, how do you do that ?

Joe,
I had never heard of terra preta before. I've read all the articles you referred to. It sure sounds more than promising.
From what I've read, no-one was able to recreate terra preta by simply adding charcoal to soil. In the tests they added 20% (weight) of charcoal to the soil. That's a lot of charcoal if I have to go 4 feed deep!
Have you tried it ? How did you do it? What are your experiences?

__________________
With kind regards
Wim