Biochar - The modern version of Terra Preta

Terra Preta (also known as "Amazonian dark earth" or "Indian black earth") is a manmade, pre-Columbian, very dark, fertile soil found in the Amazon Basin. It is believed to have been created by humans between 450 BC and AD 950. See here on details of its composition, and watch the BBC Video: The Secret of El Dorado on the story behind it. "As much as 10% of Amazonia is covered in terra preta." --Reference. Also read: Terra Preta Magic Soil of the Lost Amazon.

Biochar is a modern attempt at duplicating the ancient art of producing terra preta. Biochar is charcoal made by baking (instead of burning) wood--it is smoldered at low temperature, then combined with a 50/50 biochar to compost mix to make a fertile soil. "Microbial growth substantially improves with charcoal. It may be that small pieces of charcoal migrate within the soil, providing a habitat for bacteria that decompose the biomass in the surface ground cover. This process may have an essential role in terra preta's self-propagation; a virtuous cycle develops as the fungus spreads from the charcoal, fixing additional carbon, stabilizing the soil with glomalin, and increasing nutrient availability for nearby plants." --Reference

Biochar Sellers

• Biochar from DOLLAR STORE. Buy Royal Oak Hardwood Lump Charcoal. Approximately, $10 for 15.4 pounds.
• RockwoodRecycling.com. Sells biochar in bulk and in bags. Located in Lebanon, TN.

BioChar links

• THE ULTIMATE GUIDE TO BIOCHAR: how to make it, how to use it, and why it's important. Duration 33:13. Uses a 55-gallon metal barrel with just an open top. Very simple approach.
  • Load the barrel about 1/3 of the way with wood pieces at the bottom, newspaper (to start the flame), and branches.
  • Pour in about a cup of 90% alcohol to get the fire started quickly. Throw in a lighted match!
  • Add layers of larger brush and wood as contents burn down.
  • Toward the end of the process, as the barrel fills up, add smaller branches so that it continues to burn hot.
  • Step 3: Fill the barrel with water (and as much urine as you can supply) to extinguish the burn. The urine will add nitrogen into the biochar. Let it sit for a day or two.
  • Step 4: Dump the contents of the barrel on the ground (or use a shovel to scoop it out) and then crush the big pieces into roughly pebble sizes.
  • Step 5: Add some compost and cow or chicken manure (use store bought bags, if you don't have any other source) and let sit for 3 months. Now it's ready to use.
• Wood Gasification: An Intriguing Emergency Fuel Source. Chris Martenson article mentions Biochar.
• (YouTube) The Promise of Biochar - Part 1. Here is Part 2.
• International Biochar Initiative. Lists regional BioChar groups like Biochar Northeast Association.
• Sonoma Biochar Initiative. A California BioChar group has a nice video comparing Biochar to Terra Preta.
• Biochar Discussion List Website.
• Introducting Biochar into the Garden Soil. Use about 10% of Biochar + fertilizer in other soil. The series is found at Berkshire Harmony.
• Making Biochar. Video showing biochar made in Vermont by the locals here.
• Low-cost retort kiln called the "adam-retort". Pictures of another large-scale adam-retort in Biochar Project Australia.
• (YouTube) Small Biochar system in Costa Rica. This video illustrates a new biochar kiln design which we call "hornito", meaning small oven in Spanish. This kiln is a clean, efficient and inexpensive design for producing high quality biochar using recycled 55 gallon drums. The kiln is in operation in the south of Costa Rica. Hornito Biochar Kiln diagram.
• (YouTube) Simple Biochar Kiln using 55 gallon drums. The Biochar Kiln is a top-lit updraft (TLUD) design. The biochar process described is scalable for small acreage farms. The set up of four kilns is capable of producing one cubic yard of biochar in six hours. They use wood chips.
• Corn and Sunflower Test with Biochar. One month into growth. Biochar runs 20-30% better on corn and 100% better on sunflower. And final video here.
• Biochar Kiln Technologies (PDF). Shows various designs including the Hornito Kiln from Costa Rica.
• (YouTube) 4 Tips on how to buy biochar. Biochar needs to be precharged and innoculated with compost and water, since it's very absorbent.
• (YouTube) How to buy biochar. (1) Buy in dry weight (since it can absorb 10x of water), (2) test quality with tap water, (3) do not apply raw biochar to garden, (4) know your soil (e.g. pH level)--Biochar has liming effect of ph 8 or so.