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Biochar, A Brief History

Biochar, while boasting an ancient history, is actually just gaining popularity among many circles today. While it’s believed that ancient South American cultures would use biochar (or burning agricultural waste, covered in soil) to increase soil productivity, the term wasn’t coined until Peter Read did so in 2005, to describe a substance that looks almost like charcoal, but that is actually biomass carbonized and made into a solid material, used to improve soil functions and reduce greenhouse gas emissions.

Understanding biochar, its use and its demand, however, is somewhat complex, and it starts with a firm grasp of carbon. Carbon is never destroyed. When you pull carbon out of the ground, whatever form it happens to be in, and burn it, you’re releasing it into the atmosphere. If our plant life is not able to take that carbon dioxide in quickly enough, it stays in the atmosphere or it sinks down into the world’s oceans. Then, depending on where it goes, the carbon creates warming effects (i.e. global warming), extreme weather events or issues within the marine food chain.

However, as stated above, the ancient Amazonians had a somewhat simple solution to this scientific problem, that all started with a system they would use to increase their soil fertility. When looking at soil fertility in the region today, it’s often not terribly high. The light-colored, nutrient-poor soil is only usable for short periods of time by agricultural workers, and is then no longer viable. However, some pockets of soil remain that give us a glimpse into the ancient Amazonians’ process.

Thousands of years ago, these civilizations would dig large, deep earthen pits. They would then fill these pits with food scraps, agricultural waste and anything that would decompose organically. They would then set all of this waste on fire and cover it with soil. The practice created a condition allowing for extremely high heat and very low oxygen. The carbon created from burning the waste would then be retained in the soil, rather than being released into the atmosphere. This created soil that was very dark in color, very rich and very nutritious, as it was filled with charcoal, covered in microscopic pores and very dense, working to act as a sponge and hold nutrients that would enrich soil and improve fertility for thousands of years. Biochar is simply the modernization of this process.

In modern processes, organic waste materials (such as food wastes and agricultural wastes) are being saved from being sent to landfills. These wastes are heated to a very high temperature in a low-oxygen environment, creating the biochar you see today.

Household bio organic food waste

You’re probably asking — why not just compost? Creating biochar actually sequesters approximately 50 per cent of the carbon that would otherwise be released. Composting only sequesters up to 10 or 20 per cent, while burning the waste only sequesters about 3 per cent. Plus, studies are showing that biochar creates a stable carbon sink, and has the potential to put a huge dent in the carbon dioxide the human race is off putting. It improves soil fertility, increases the water-holding capacity (reducing irrigation needs and saving water), lowers soil density to create well structured soils with larger root mass and then produces larger plants with higher plant yields.

Biochar therefore has the potential to assist with two of the largest sustainability problems in today’s world — the growing amount of trash being produced by the world’s population, as we take a portion of this trash to be used as biochar, instead of being sent to landfills that are being capped off or close to being capped off, as the trash is not going away at the rate at which we’re producing it; and low-performing agricultural fields covering 38 per cent of the world’s terrestrial surface, causing 1 in 7 people to be food insecure.

Biochar is becoming a large movement, though, currently, biochar isn’t popular enough to really contribute to the global carbon budget. However, its expansion of use is being more widely recognized. For example, the Biochar Fund is using biochar to slow deforestation in Central America, while simultaneously increasing food security and renewable energy. In Sweden, urban tree plantings use biochar to increase soil fertility and, in Qatar, the same is used to assist trees in weathering the intense summer heat.

The U.S. Biochar Initiative promotes the use and production of biochar in the United States. One of their large projects is to increase biochar awareness in a country where many may have never heard of the solution. The U.S. Biochar Initiative works with The Biochar Company, created by Jeff Wallin, to market and develop the use of biochar not only in the United States, but in other countries as well. In fact, it’s The Biochar Company that’s home to one individual who is becoming the face of biochar though many projects — Biochar Bob.

Biochar Bob, of course, just started out as regular Bob, a high school student who was lucky enough to hear Jeff Wallin come and address his biology class. Wallin gave Bob, who was fascinated by the topic, the opportunity to intern for The Biochar Company, leading to a successful partnership which not only made way for the creation of Biochar Bob, but also the spread of the good word of biochar. Since their partnership, Bob has been working with groups on the East Coast, in Hawaii, Costa Rica and now the Dominican Republican.

For more information regarding biochar, Biochar Bob or the U.S. Biochar Initiative, visit the links provided


  1. I have used this method for years , great method to sweeten the soil , burn off weeds an brush also, must be kept controlled an have prepared methods to douse the fire ….! Best to burn in small rings or circle areas an no wind blowing !

    1. Open burning does not create biochar. Open burning creates ash. Biochar is made with “cold pyrolysis’ when oxygen levels and temperature of the burn is slowed. This leaves the cellular structure of the plant in place. The burned out cells become sponges for water and holding places for mycelium. Good stuff!

  2. I like this, much thanks for publishing it!

    If you think hundreds of men were led by some sort of warlord to create an agricultural paradise in the middle of an overgrown, oxygen-depleting old growth jungle, stop. Men were the bulk labor, yes, but aggie in Native America was a woman’s labor of love. Women owned the fields and hunting rights. Men worked hard, because that’s why man is here, to stand between Woman and danger. Think a group of elderly women studying nature. After a forest fire, plants grew faster and better than before. Women were our agronomists. It had to be tasty, but also be pretty, which is why so much of our food crops are also considered ornamental (achira, beans, nasturtiums, peppers, ect.).

    Biochar absorbs a lot of water, which meant they could plant and harvest during the dry season, when even the Amazon tends to become a trickle in many areas.

    Move into a river’s flood plain. Dig out what you want to grow food in, pile the soil as a dike around the area. Cut in a water gate. Fill in the pit with brush and so on, burn it (which also chases off insects and vipers). Let the river flood it, close the gate and go fishing and when the water recedes, it leaves rich topsoil and then you can plant. When the crops are done, burn them off to kill diseases and pests, add brush and burn that, as well, and then let the river flood it again.

    Up north, people used beaver dams for cattails and other aquatic foods. Wild rice was popular. After so many years, the dam would silt up (and the beavers moved on because the cattails were not doing well), and a water gate was cut in the spring to drain the dam and maize and a dozen other things were planted. Every few years the gate was closed for the winter to flood and re-fertilize the soil. If you’ve ever read The Plowman’s Folly, the author’s father did something related, allowing a stream to flood his cotton field, leaving leaves, twigs and so on.

    A number of farmers are buying coal dirt (the fine dust from crushing coal) to add to their fields. Bituminous is better than anthracite, which is so hard it’s like glass. Lignite would be far better as it’s closer to biochar. Please remember, lignite can burn from spontaneous combustion if piled too thickly (a meter or so). A few centimeters tilled into the soil should be more than needed to replentish soil carbon.

  3. Biochar is not a solution. Using heat to dispose of “food waste” is not a solution. It is a decadent waste of resources that could otherwise be contributing directly to soil heath and biodiversity. It is an excuse to burn municipal waste streams, which are often contaminated with unknowns, and profit from this.

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