Biochar seems to be the latest new craze in everything agriculture and biofuel related. It seems a term we are all going to be hearing a lot more of soon.
The basic idea is green waste is converted, by means of a process called slow pyrolysis, into a high carbon byproduct that is beneficial to soil fertility. By adding it to crop land not only is the need for fertilizer inputs reduced, but the carbon is trapped in the soil for potentially thousands of years. The process of slow pyrolysis also produces energy that can be converted into electricity in a similar way as burning biomass.
National Geographic recently ran a program on Terra Preta soil discovered in the Amazon rainforest, apparently as a result of an ancient civilization that built up their soil with biochar. Alan of Bishop’s Homegrown recently made a post on this, and expressed an interest in making his own biochar.
On the other end of things Archer Daniels Midland (ADM), the largest food processing company in the US, is preparing for a big push with this technology. They see biochar working together with GM crops, used for food and biofuels, in a supposedly sustainable and environmentally friendly way.
Personally, I find it very exciting that someone like Alan is working on it on his own farm. It would be great if it turned into a way to make local and small scale agriculture less dependent on chemical and other inputs, and increased productivity. Likewise, I find it very suspicious that anything good can come from ADMs interest in the technology, and doubt very much they will implement it in an environmentally friendly and sustainable way in the end.
I suppose my issue with this is when you hear things and ‘this will help remediate global warming.’ I worry when instead of limiting the causes of the problem, we try to create technological fixes which may carry their own risks.
My other concern is the source of the biochar… is that we are taking ‘trees’ or other organic matter and converting them into the char. If this proves to be a more effective way of transforming organic matter into nutrient rich self-sustaining soils than I’m all for it, but I would hate to see people feeling the need to cut down trees to make char.
Anyhow, it will interesting to see what Bishop’s Homegrown experiments reveal!
Would be interesting to explore the Mayan soils (e.g.Tikal)for biochar.
We had some very black, charcoaly soil at my old place that took awhile to build up, or release maybe, its fertility, but once started was amazing. Soil tests always came back different!
Hi Ottawa gardener…hersion indeed!
P.S. I will soon update my theory on my blogsite as I am constantly re-evaluating this in my mind.
Hey buddy,
I tried to post some more relevant information about what I was working on but for some reason it wouldn’t go through on the site, it said I was making duplicate posts for some reason or another. Anyhow, thanks for the plug, I appreciate it and I’ll definitely be updating the work as I go!
Ok, I’ll try to post once more.
Basically my new idea is; why bring the worms to the charcoal when you can bring the charcoal to the worms. In other words I will create my charcoal, soak it in a nutrient solution and then apply it to my worm bins in the new and improved worm house I recently blogged about. In this way the charcoal (which will be buried in the 36″ deep bins) will be able to absorb nutrients from the worm castings/compost and will also be inoculated by the beneficial soil microbes. Of course this will be applied in a two layer hill system as described in my original blog and will still entice the local endemic earthworm populations as well as the local endemic soil micro-organisms to come check things out but then there will be less waiting as the majority of the nutrients will be laying in wait for use by plants, as the nutrients escape the worm castings they will be caught up by the charocoal (which is slowly releasing the nutrient it was soaked in as well as the worm casting/raw compost nutrients), In such a way I will have created a time released version of worm castings/compost and implemented a very simplified form of Terra Preta on my farm.
One place where I think that folks into the bio-char method make a mistake is in considering bio-char and amendment in and of itself. Too much char and you get a nutrient lockup, same thing happens with too little fertilizer input, it’s going to be a delicate balancing act which will take many years of research, but in the end I feel will prove worthwhile.
I do believe that most of the corporate driven interest in bio-char is coming from orginaztions interested more in profit than actually contributing to stoping global warming or amending organic soils in a beneficial way, I do think as a carbon sequestration method it has it’s merits, but if the common person can’t afford it then what good does it do? It is up to us independent gardeners/farmers and innovative seed savers and organic fanciers to divert this ancient technology our ancestors have left to us from the hands of the companies that got us into the mess we are in in the first place.
I definitely also agree with Ottowagardener about not going out and cutting trees or other plant material for the express interest of making char, the only eco-logically sound way to do this is if it is of a self-sustainable nature to begin with, using only the biproducts of agriculture or forest management. As an example using my method of collecting charcoal, I consider the method carbon neutral for various reasons, though we do emit some amount of carbon heating the greenhouses with wood, the wood comes from a plant that creates shipping palletes and so therefore would normally be considered a waste product and allowed to rot, so the wood has already been felled and it is the byproduct of an agricultural practice, the wood which we cut from our forrestland is wood that has already been felled by natural forces and would otherwise become a liability in the form of wild fires or dangerous hiking situations, since we plant trees every year and we also have a wood lot of 25 acres I would tend to think this would make up for our carbon foot print in some small way, as well we will be using the charcoal to sequester carbon in the soil so it can’t be all bad.
For those interested in making their own charcoal but without a source of it as a byproduct (IE a woodstove) I suggest using agricultural residues and creating a low oxygen environment using only recycled materials like metal barrels and fire brick.
Hi
Right. research is best from many small actual situations. Collaboration and communication is key.
Also. Could pyrolysis not occur naturally? say in a cedar forest in a marsh, burning hot, trees fall, roots in water, continue burning?
Hi Anne,
I think you’re right, maybe it could occur naturally.
And, yes, if people don’t get together and do this research themselves, no one else is going to do it for them!
I am just wondering if the process I use here in France is actually making something like char. In autumn and winter we burn the collected waste, hardwood clippings, brushwood from the coppiced woodland (about 23 acres/ 8 hectares) along with diseased plants and non compostable debris from the veg gardens. During the year I collect it in huge piles. Then when the weather conditions are right (ground is wet but pile is dry and no wind) I burn it for several hours then cover with a layer or turf taken from the surrounding area turned upside down onto the fire. The pile will then burn slowly, retain mass but not get out of control (I am paranoid about starting a fire here because the whole mountain went up in flames about 20 years ago or so I’m told). Anyway I then spread the resulting black soil and charcoal over the vegetable beds and it really does seem to improve the soil particularly for alliums, brassicas and legumes.
I think I got the idea for burning it like that from a project I did on one of the orkney Islands, over 20 years ago now, where we built a huge peat wall as a coral to demonstrate to the kids the ancient farming methods once used on the Island. The coral was 30ft across and about 5-6ft high it was then covered with a top layer of heather turf which was burned to strengthen the structure.
Laura,
This is really interesting.
You mentioned this before in connection with growing garlic, and I didn’t think bonfire ashes would do much. Like you just pointed out, maybe you’re really making biochar, which could be something totally different.