Camino Verde News

Black is the new green
August 31, 2009

Throughout the tropics, and especially in the Amazon, soil is remarkably fragile.  Countless millennia of torrential rains and desiccating sun have left most tropical soils poor to the point of sterility.  As Wade Davis describes in One River, "the tropical rainforest, though home to tens of thousands of species, is in a sense a counterfeit paradise, a castle of immense biological sophistication built quite literally on a foundation of sand."  Some scientists estimate that in the Amazon, well over eighty percent of all nutrients are bound up in the living bodies of plants, animals, and fungi.

The forest itself is a closed circuit for the extraordinarily efficient recycling of any and all available supplies.  In The Burning Season, Andrew Revkin notes, "The Amazon forests must be self-sufficient, because the ancient soils beneath most of the basin have long ago been leached clean of minerals and nutrients.  Only 4 percent of the Amazon has what agronomists consider fertile soils."  Destroy the forest, as in slash-and-burn farming, and the exposed ground quickly loses any remaining semblance of fertility.  Enriched by the ash of burnt organic matter, a typical farm can support a year or two of annual crops like corn or rice before the plot must be abandoned and new forests cleared; the vicious circle continues.

In the second half of the twentieth century, scientists rediscovered terra preta (simply, "black earth"), also known as Amazonian Dark Earth, an anomalously rich soil with a deep black color.  It was soon suggested that terra preta is an anthrosol, or human-made soil, a hypothesis that has been confirmed with further research.  Certain groups of Amazonian Indians, likely living in organized communities that were more structured and stratified than previously thought, created this fertile soil through the incorporation of organic matter and, importantly, charcoal.

Whereas slash-and-burn farming provides a quick fix of nutrient-laden ash that rapidly leaches from the exposed ground, the charcoal in terra preta acts in much the same way as activated charcoal in water filters: it tenaciously clings to particles and nutrients, preventing them from being pummeled out of the ground by rain and sun.  Though containing few available nutrients of its own, the charcoal's surface grabs onto minerals and nitrogen-based compounds and makes these available to plants.  The result is a phenomenally stable soil; the oldest plots of terra preta discovered date to two thousand years ago and continue to be productive.

Without a doubt, terra preta represents a potential paradigm shift in notoriously fragile tropical agriculture.  Interest in the use of "biochar" (organic matter carbonized into charcoal through a low-oxygen burn) as a soil amendment has sprouted up everywhere from Brazil to Cameroon to India.  The stability of charcoal in the ground has also created interest in terra preta as a significant carbon sink.  Recently, terra preta has attracted the attention of mainstream media, thanks in part to the research and efforts of Charles Mann,  National Geographic contributor and author of the popular science bestseller 1491.  For further information, please follow the links below to articles in The Financial Times ( and
Nature (

Over 1100 trees planted at the end of the season
June 30, 2009

With the closing of May comes the end of the rainy season.  The almost daily storms common to February and March settle down into bi-weekly showers that usually coincide with the full and new moons.  Weed growth slows down and many trees flower or temporarily shed their leaves.  The onset of the dry time of year also marks the end of our planting season.  Like most farmers in the Peruvian Amazon, we rely on rain rather than irrigation to get our plants established.  When the rains let up, our planting comes to an end.

It was our goal for the wet season of October 2008 to April 2009 to plant over 1000 trees at our center in the community of Baltimori.  We are pleased to announce that the final count for this time period is well over 1100, with trees planted from dozens of species.            

To date we have planted nearly 150 species of trees.  We also protect many more species in Camino Verde's private conservation areas.  It is our goal to have planted over 250 species of trees and to have identified over 250 more in our protected virgin forests by 2015.  We also have committed to plant 1000 trees or more annually for every year between now and 2015.  To find out more about the remarkable trees that are the foundation of our work, please refer back to our constantly growing Tree Database.

Food Forests, Living Seed Bank
First phase of construction complete
May 31, 2009

We are pleased to announce that the first phase of our Supporting Indigenous Wisdom project for 2009 has been completed with great success.  We have put the finishing touches on the first of two buildings being built in service of the home health practice of an Amazonian herbalist in the native community of Infierno on the Tambopata River in Madre de Dios, Peru.  This building will allow visitors and patients to undergo treatment in comfort and with privacy.  Additionally, the roof for the second new building is up and materials have been procured locally to complete the project. 

 All labor in the construction has been performed by local contractors hired at fair wages.  Funding through Camino Verde has been matched monetarily and in labor by the beneficiaries of the project.  We thank all of the many donors who contributed to this effort specifically and we continue to welcome support for the completion of the final phase.


Supporting Indigenous Wisdom