Making biochar can either be easy or over complicated.
The easy way is to simply burn wood in a pit and then pour either sand or water over it before it turns into ashes. Once it is ashes it is no longer biochar.
The complicated way is to burn woodchips in a specialized (expensive kiln).
Good materials for making biochar
I personally found that the best materials for making biochar are coconut husks or small impractical bamboo sticks, or branches of trees with thorns.
The only reason being is that coconut husks take a very long time to decompose and thorns are not a good thing to use as mulch.
I do not like using large amounts of wood or woodchips for making biochar, because I feel like it is much better to use them as mulch and organic fertilizer. Large branches and fallen trees are often the home of many insects and turning their homes into biochar reduces biodiversity. I always try to put biodiversity above all else.
Deforestation and charcoal
It feels a bit weird to make char because charcoal production is the major contributor to deforestation in my area. Giant towering magnificent trees are cut down to make charcoal in large quantities.
Every day I see people going to the forest with chainsaws in the morning. Then I hear the roar of chainsaws and later smoke coming from the mountain. Sometimes it is a bit closer to the farm and I can hear the huge trees crashing down like thunder. Then in the afternoon the people come back armed with guns and weapons with hundreds of big bags full of charcoal.
The charcoal is sold and sent to the capital Manila so that the citizens can barbecue and grill their meat. It is a true shame.
When to use biochar
Biochar only works well for the soil if all of the following conditions are met:
- The soil is already relatively fertile.
- The soil already contains some microorganisms, especially bacteria and fungi.
- The soil is not bare and exposed to the sun.
- The soil is not plowed nor tilled.
- There is a layer of mulch on the soil.
The way biochar works is that it traps nutrients and houses bacteria and fungi, biochar itself does not have any nutrients except carbon, and even the carbon itself is partially locked up.
Thus any farming practices done that kill off microorganisms and increases soil erosion will greatly decrease the usefulness of biochar.
While reading about biochar I saw people becoming obsessed over the biochar almost to a point of it being viewed as some kind of magic dust.
I see people making giant complicated kilns for producing biochar; chopping down trees to produce it; burning mulch for biochar; and adding biochar to bare desert-like lands.
As a natural farmer, I am not interested in just the soil. I am interested in the well-being of the whole ecosystem. And ecosystems are complex interdependent connections.
The soil is the foundation of the vegetation, but trees are the protectors of the soil. One can not live without the other. So if one cuts trees to make biochar to improve the soil the effect is null. First of all when a tree is cut it causes immediate soil erosion and kills microorganisms. Second, if a tree is burned all nutrients except carbon are released into the atmosphere, this same kind of nutrients could have just been returned to the soil by decomposition through fungi and other beings. Remember biochar only gives housing to microorganisms it does not actually feed them, without the food of organic matter for the microorganisms, the microorganisms will not thrive. A house without food can not have anyone living in it.
When burning off mulch one also eliminates nutrients, removes the food for the microorganisms, and removes the protection from the soi; causing the soil to dry out more rapidly.
I also see people burning off big logs for charcoal, in a way I think that is really sad because I personally think it is much to just as easy to place the logs underneath or near trees to use as nurse logs. One can even use the logs directly to grow mushrooms such as shiitake.
Whenever I do an action on the farm I ask myself: “What are the benefits? What is the price or sacrifice of this action? And what is the effort?”
For example, I have huge piles of sawdust and woodchips leftover from the construction of the house. I can essentially do 4 things with it.
- Turn it into compost.
- Turn it into biochar.
- Till it into the soil.
- Directly put it on top of the soil and use it as mulch.
For the 1st one, I would need to make a compost pile, carry all the woodchips into it, turn the pile, and finally spread the compost over the land.
For the 2nd one I would need to haul all the woodchips into the kiln, fire the kiln, harvest the charcoal, grind the charcoal, and then spread the biochar.
For the 3rd one, I need to get a tractor or tiller and turn the soil while spreading the woodchips.
For the 4th one, I simply need to collect the woodchips and spread it.
The first one would require the most effort and I would need to wait a very long time before I get the benefits of compost, not only that but the volume of the woodchips would have been reduced resulting in not enough compost for the plants.
The second would require moderate effort and the benefits of biochar. But again the volume of the woodchips would be dramatically reduced and all of the nutrients from the woodchips, except for carbon would be burned off.
The third one is not possible for me, because I only do no-till farming. Because tilling destroys the soil, thus going in the opposite direction of what I want to do.
The fourth requires the least amount of effort. It would also provide the direct benefit of weed suppression, moisture retention, and a safe place for insects to crawl in. In the long term, the wood decomposes in place providing food for fungi, mycorrhizae, and wood and fungi-eating insects. Then in the end I will have the same benefits as adding finishes compost to the soil.
So as you can see, at least in natural farming the action that provides the least effort with the most benefits is usually the right action. Usually this is also the action that mimics nature the most. Woodchips kind of also exists in nature. I have had several logs on the farm that as they were slowly broken down by fungi, termites, rain, heat, and so on it turned into a very fine crumbly woodchip kind of texture. Plants such as taro started growing into the half-broken-down log.
The only person I’ve seen using biochar in an excellent way is John Kaisner.
I think when people hear about the benefits of biochar they become too obsessed about it and only focus on this one part using any means necessary to create biochar, I think this is a kind of narrow obsessive thinking.
When solar panels first became popular I was worried people would become too obsessed over them resulting in forests being cut down to make room for solar panels.
Now many years later I am seeing numerous news articles pop up about companies, governments clear-cutting huge forests to build solar panels, even individuals felling trees to have space for solar panels. It is a sad reality people are destroying nature under the belief of saving nature. I fear the same thing will happen with biochar.
Seeing the whole picture
Biochar alone will not save the world. Planting trees alone will not save the world. Mushrooms and fungi alone will not save the world. Compost-tea alone will not save the world. Whatever latest environmental technique there is will not save the world.
All of these together will help restore stable self-sufficient ecosystems, please do not get hung up on a single thing or else you will not see the whole picture and are just limiting yourself.