Interested in Terra Preta ? (B. FIELDS / Willem)

A couple of days ago, Bruce FIELDS from Chicago has sent an interesting message on “Terra Preta”.

On March 14, 2008 I posted a text on Biochar from Wikipedia :

“Biochar is a type of charcoal produced from biomass. In some cases, the term is used to distinguish biomass charcoal produced via pyrolysis.

Biochar is employed most commonly as a soil amendment. It has several qualities that make it suitable to this task:

  • It is largely inert. Microbial composting action leaves charcoal largely unaffected.
  • Highly porous. Serves both to retain water in the soil or improve drainge , and provide a large surface area for microbes.
  • It is of neutral or alkaline pH . Reducing the acidity of , or sweetening the soil .
  • Very high cation exchange capacity . Increasing the uptake of minerals such as Ca , K , Mg and P .
  • It is a good insulator . Reducing average soil temperatures in hot climates .

There is some empirical evidence that low-temperature biochar produces more robust growth in plants when compared to high-temperature biochar. It is speculated that it retains organic matter that is desirable to beneficial microbes (like mycorrhizal fungi), resulting in higher nutrient availability to the plants.

Biochar is the main (and likely key) ingredient in the formation of terra preta, or Amazonian dark earth. Efforts to recreate these soils are being undertaken by companies such as Eprida, Best Energies, and Dynamotive Energy Systems. Research efforts are underway at Cornell University, the University of Georgia, Iowa State University, and The University of Hawaii at Manoa. One focus of this research is the prospect that if biochar becomes widely used for soil improvement, it will involve globally significant amounts of carbon sequestration, remediating global warming.



Today, Bruce FIELDS says :

“Are you familiar with terra preta, “the intentional use of charcoal in soil”? I only know a little about it, but it seems incredibly promising. At least from a growing point of view; politically it’s much tougher to see how it could be implemented.

Here are a couple of links for you :

And I’d like to point you to the website of Phillip Small, another soils expert who you might enjoy. I had some basic questions on terra preta and exchanged a few emails with him. He was very helpful.


Going to :

I found interesting texts on :

Agrichar Video
Australian Broadcasting Corporation, 2007

Video on Agrichar, International Agrichar Initiative conference (April 2007), BEST Technologies, and use of agrichar in Australia. – A New Website for the Promotion of Biochar Research and Experimentation
Chris Braun. February 27, 2008

A new website for the promotion of biochar research and experiments was born !

You can there discover several biochar-related projects, most of them still in active development . If you are performing biochar soil amendmend trials yourself, your contribution to CharDB or to the Field Trial Portal would be highly appreciated!
And if you haven’t done it so far but would like to start experimenting, you can also find useful resources, links and contacts to help you.

This website is still in its infancy and any constructive comment, critic, question, advice… is very important for further development ! For that you can use the devoted forum:

Thanks for your contribution!

Sincerely yours,


Effects of mycorrhizal fungi and biochar 90 Days

Robert Flanagan, Hangzhou Sustainable Agricultural Food & Fuel Enterprise Co., Ltd. (SAFFE), February 15, 2008

Hey Guys, Just got to 90days of my latest biochar trial and wanted some feedback on what data you think I should be taking from this trial? We can clean off the roots and photo as much as possible and do clearly marked side by side photos.

I don’t have any funding for this trials so there is a limit on the depth I can go regarding data collection so I’m really looking for a base list. The medium was sterilized subsoil and we used 2Kg soil per tray with three reps of each treatment (I just took the average of each treatment for the attached photo).

Kind Regards, Rob.

Robert Flanagan
Chairman & President Hangzhou Sustainable Agricultural Food & Fuel Enterprise Co., Ltd.


This is a fine website, which I can recommend to the readers of my blog interested in Biochar (Terra Preta).


Published by

Willem Van Cotthem

Honorary Professor of Botany, University of Ghent (Belgium). Scientific Consultant for Desertification and Sustainable Development.