Biochar - does it work?

[DartmoorEwe]

We make charcoal and sell it at the gate and local farm shops. A waste product is charcoal dust that gets sieved out. I have seen charcoal dust sold as biochar that people add to soil to help fertility. It is the basis of the super soils that are found around the rain forest where the incas had perpetually fertile soil. I'm wondering if anyone on this forum has used biochar and what their experience is with it. I'm also wondering, irrespective of its actual effectiveness, if I could sell charcoal dust as biochar.

Any thoughts or opinions?

 

[PSQ]

Hmmm, there was a review of scientific papers published a few months ago that said there was little yield benefit found in temperate climates, but lots of benefit in tropical climates.

- The real high value market would be bagged product in garden centres

Having said that, it would make an interesting long lasting trial plot. How much would you want for a 2 cube tote bag full, ex your yard???

Edit: found it - http://iopscience.iop.org/article/10.1088/1748-9326/aa67bd

 

[T C]

http://nuffieldinternational.org/live/Reports
Scroll to 06/08/2010 Nick Ward "Arable input efficiency" - chapter on it there.

 

[New Puritan]

I've wondered about it. It seems expensive for what it is, but that would be in your interest @DartmoorEwe ...

I had a chat with a guy who runs a company promoting it as he lives near me - the same guy that set up Green & Blacks chocolate. He was an interesting character.

A couple of my fields used to be woodland until the 1950s, and coppicing used to take place. Here and there are very black patches of soil where the processing used to be. I've noticed the crops always germinate there first. I certainly think the soil is better there, but couldn't say it's specifically down to charcoal being in it, it could be all sorts of things.

 

[DartmoorEwe]

Thanks for the replies, I'll read the scientific papers when it gets dark. Too much to do outside at the moment.

How much would you want for a 2 cube tote bag full, ex your yard???

Interesting proposal. That would be quite a bit of wood and quite a bit of making. I'll work it out and let you know.

I've noticed the crops always germinate there first. I certainly think the soil is better there, but couldn't say it's specifically down to charcoal being in it, it could be all sorts of things.

So whatever is good about the burning plots seems to last so it cannot be simply enriched soil from the fires because that surely would have been used up long ago.

Perhaps black soil absorbs heat and warms it making it more productive sooner. Have you had the soil in the black patches tested compared with the other areas? I wonder whether there is an optimum concentration and whether I should fortify it first. And if I fortify the biochar I should also fortify other areas without biochar and see if they perform differently. Can I top dress or should I plough it in? I can sense several test plots coming on. Maybe my diversification should be into scientific testing.

Irrespective of how it works, if I were to sell the stuff mail order in 1kg bags, are there any regulations I need to look at? Can I fall foul of trade descriptions - what is the best way of limiting the risk?

 

[PSQ]

I don't think a 1kg bag will go far.

The median application rate in the study was 30t/Ha, so 1kg will only cover 0.33m, or about 3 square feet.

Given the distance from Dartmoor it might make more sense to source some charcoal locally for a trial.

 

[Clive]

I did quite a lot of research into this last year, did seem to be a very good case for it

lacked time to follow it all up !

 

[New Puritan]

@DartmoorEwe - from what I recall, the selling point is that some sort of fungal population develops in the tiny nooks and crannies of the pieces of charcoal. As the charcoal is almost indestructible in the soil, it provides a permanent habitat for these fungi, and they then have a beneficial impact on the soil. I'm remembering this from what a company who make it told me though, it would be worth reading up on what scientific evidence there is too.

The other advantage of it was on helping people in very poor countries cook their food more efficiently. I think part of the rationale of the company was that they wanted to see if they could improve the charcoal making process, as very little research (apparently) has gone into making charcoal burning more efficient in 100s of years. By producing charcoal for cooking using cocoa production waste they wanted to help the cocoa producers improve their lives.

Sorry but I have no idea what regulations cover agricultural / horticultural additives... I would have thought provided you don't make unsubstantiated claims for it, it should be alright if your normal charcoal business is compliant with everything it needs to be? Others may disagree.

 

[New Puritan]

Just looked at this: http://www.carbongold.com/wp-conten...iochar-temperate-yield-datasheet-Nov-2014.pdf

1 tonne / ha increased yield by 20% growing OSR in Canada??? Really?

 

[PSQ]

1 tonne / ha increased yield by 20% growing OSR in Canada??? Really?

An interesting outcome, as OSR doesn't support 'arbuscular mycorrhizal fungi'.

 

[TripleSix]

It doesn't matter if it does much good.

Market it correctly and it'll sell....

 

[New Puritan]

@DartmoorEwe - how did you get on with this?

@Old McDonald - you were thinking of building a biochar thing weren't you?

@Kiwi Pete - is biochar one of the things you do?

How do people who use biochar spread it? I've been reading up on it and would like to have a go. A friend of a friend has built a biochar maker and I've got plenty of branches and suchlike he can use. I've got a pond that needs dredging and clearing, and have an idea to heap the dredged material up to let it compost a bit, mixed up with biochar from all the stuff I'll also be cutting back from around the edge.

 

[Old McDonald]

@Old McDonald - you were thinking of building a biochar thing weren't you?

I did have a look at it. I wanted it for a specific non-agricultural purpose - the medium in an aquaponics grow bed. I found it easier to buy some bags of charcoal. I topped this with just enough gravel to stop it rising when the beds are flooded with water pumped from a lower level fish tank. It then returns to the fish tank with the aid of a bell siphon. Early days, but it works.

My interest in charcoal/biochar goes back a few years though, as a means of using tree prunings (1300 olive and almonds) rather than burn them as everyone else does. I unow use the bigger stuff for the house heater and the small stuff is being used as a sort of mulch in a wet area and sown with lupins/rye/other legumes. I have posted previously that I will report back on this in due course - probably next year, but I like the look of what is happening so far.

 

[Kiwi Pete]

I've been making a bit... not a great amount yet as have been fairly flat out while the weather's been so good!
But my set-up is very simple, it's a Top-Lit updraft machine built out of an oil drum.

I just filled my slug pelleter and put it on the side of a hill that's very thin, but the eventual plan is to add it to my compost.
Biochar is one of those things that is greatly more beneficial if you 'activate' it- it has a huge surface area- so will possibly dunk it in with my seaweed concoction to infect it with microbes.
Otherwise it's very sterile.

Hope that answers some questions, NP, hit me with as many as you like!

 

[Danllan]

Interesting subject. Obviously based on empirical experience rather than science, but the market gardens and farms around London, and much further afield, in the 18th and 19th Centuries took massive amounts of ash - wood and mineral - and dust etc. from London and had some remarkable yields for the time when compared to other areas.

Has anyone tried it on PP with notable benefits, if so at what rate?

 

[New Puritan]

I sat through the various parts of this the other day:

.

Some of it was not hugely relevent and without wishing to sound like a know-it-all, it was possibly aimed at a lower initial level of knowledge than I have, but I nevertheless picked up a few things from it. As @Kiwi Pete says above, activation seems to be the key hence my thinking I could mix it with the pond dredgings. It got me thinking about cation exchange capacity of soils as well.

And as @Old McDonald mentions above, it might be a good way of processing branches / prunings which I'll also get a load of when I clear the pond rather than just burning them.

It all seems like a great idea while sitting in front of the computer...

 

[Old McDonald]

It all seems like a great idea while sitting in front of the computer...

That was my reaction when I first looked at it - impractical to treat any quantity of ground with the amount supposedly used by the Incas. It is (in practice) no different to lots of other "middens" - such as those mentioned by Danllan. I have seen the odd piece of ground in my travels that is now used for agriculture but was the "tip" for a local village or town.

What is now our house was originally an olive mill. I do not know the long history, but some of Napoleon's troops were billeted here during the Peninsula Wars. No idea if it was still a mill then, or had been converted. There is a small area of ground that has obviously had an enormous quantity of organic material of some sort put on it over a very long period of time, but, like growing green manure crops, it takes a lot to make a little difference.

I will stick with my mulch/compost heap idea for my prunings at present.

 

[New Puritan]

@Old McDonald - yes, I have read on another thread somewhere about your lupins-growing-through-woody-material project. What is your thinking behind this, if you don't mind my asking? Is it to do with C-N ratios in organic matter breaking down?

@Danllan - if it was ash, would it not have just been the high K in it that was doing it? I think the market gardens around London (and presumably other cities) also benefitted from "night soil" back in the day too.

 

[Danllan]

@Old McDonald - yes, I have read on another thread somewhere about your lupins-growing-through-woody-material project. What is your thinking behind this, if you don't mind my asking? Is it to do with C-N ratios in organic matter breaking down?

@Danllan - if it was ash, would it not have just been the high K in it that was doing it? I think the market gardens around London (and presumably other cities) also benefitted from "night soil" back in the day too.

High K for sure, and the night soil in vast amounts; I can't remember who authored the paper - I think it was someone in the RHS - but can recall research being done on the presumed 'waste' that was spread, ash, rag crap etc., and trying to reproduce the volumes of veg' per area that was achieved two hundred years ago, and they couldn't do it. The conclusion was that they were missing something which had been included back then.

Two things that came to my mind were, whether they got the right sort of ash - wood or mineral - and whether they used enough animal dung, the city would have been full of it. It's an interesting subject.

 

[DartmoorEwe]

The charcoal is going really well, we're getting 7 bags from each 50 gallon drum we cook and selling them for £5 each and it all comes from the smaller branches that are no good to turn into logs. We also get a bucket of biochar which goes onto the muck heap. The grass grows. The sheep grow.

I really can't morally sell the biochar for a premium (or at all) if I don't know its good stuff and if its as good stuff as some say then I don't want to sell it.