Terra preta For newbies

[Michaelangelica]

Originally Posted by mom person

When you said "Now at a field application rate of 2 lbs/sq ft", I was wondering if that is a reccommended application rate. It is approximately what I have been using on my first experimental plots.

I am not sure anyone can answer that question
It depends a bit on your soil pH before you start. Char tends to raise pH
The Japanese have a continuing experiment adding 100g per sq. mtre per Tea Tree per year and have found astounding success. But their pH is still around 6-6.5 (That is a big difference)
Some add up to 20% Char to the soil; but that is in the tropics with rain every PM.
Rain will tend to reduce pH.
Add char but ever three months or so check your pH

[Philip Small]

Originally Posted by Louis

...to make my own for the green roof..
4. 100mm deep mix of 20% charred rice husks, 30% sandy loam, 20% compost, 10% coir, 10% pottery shards, 10% mixed mature composted fish waste sand chicken manure.

The depth seems right, but I have no experience with green roofs.

The only ingredient missing I can think of is a source of calcium. If near one of those places blessed with coral sand beaches, I would think you would be set. And a little sea salt in the coral sand wouldn't be amiss for a high rainfall area: You are going to be flushing the roof, and that salt came from the land in the first place.

You don't mention, but I assume you won't be consuming the first flush, that you are going to let the system run for several flushing events, give the plants and microbes a chance to find their level, before you use this system for drinking water.

Because of disease concerns, I would generally choose not to use the fish waste, chicken manure component. It's probably less risky than walking down the street or stepping out of the shower, but it depends, and its a choice.

[Michaelangelica]

Louis I built an earth roofed mud-brick building about 26 years ago
We had a lot of trouble then getting a good waterproof membrane.
in the end we gave up and replaced it with copper sheets with an elevated joint. I think the membrane technology has improved since then
Although we never did fix the leak caused by a brain-dead Irish electrician who sawed a great hole in the roof
We used potting mix and straw, back-braking work, and that night it poured rain. I expected all our good work to have been washed away, but no, the straw stopped the potting soil from moving.

Watch the weight of your roof. We assumed the weight would be equivalent to the same volume of water.
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A good introductory article on TP

Dark Earth

* Nov. 26th, 2007 at 8:36 AM

Black Gold of the Amazon
Secrets of that ancient “dark earth” could help solve the Amazon’s ecological problems today.


.
Before the Europeans arrived, this peninsula in the heart of the Amazon was home to communities with roads, irrigation, agriculture, soil management, ceramics, and extended trade.
These civilizations were as complex as the southwestern Native American cultures that inhabited ChacoCanyon and Mesa Verde. But due to the scarcity of stone in the Amazon, the people built with wood, and over time the structures disintegrated, leaving little evidence of the culture.

One legacy remains, however: their soil. Terra preta de Indio—Portuguese for “Indian black earth”—is prized among local farmers, and it is a direct contribution of the vanished Amazonian cultures.

KEMO'S JOURNAL - Dark Earth

[Michaelangelica]

Sunday, August 19, 2007
Terra preta and the future of energy: the Secret of El Dorado
There is rapidly growing interest in the development of carbon-negative bioenergy, seen by scientists as one of the most feasible strategies to mitigate climate change and strengthen energy security on a global scale.
Two broad systems are being researched: a high-tech concept that involves storing carbon dioxide from biofuels in geological sites via carbon capture and storage (CCS) technologies (earlier post).
The other, low-tech, is based on the ancient technique of storing charcoal or biochar into soils. This practise, known as terra preta or Amazonian dark earth, could revolutionise energy agriculture.

When biochar is added to soils, they become impressively fertile because they prevent nutrients from getting washed away by rain and erosion.
Archaeologists who discovered these black soils in Amazonia are now trying to replicate the technique; soil scientists and bioenergy companies are doing the same. But some of the mystery behind these soils remains.


In an excellent documentary titled 'The Secret of El Dorado',

Bioenergy pact between Europe and Africa

[Siggy]

Hello all.

I have a few questions regarding the making of charcoal. Last week, i used a simple tin can where i burned some paper to make charcoal. The charcoal it produced was nice, allthough i didn't split it to see if it was also good in the middle. My question relates to the burning part of whatever fuel to make the charcoal. Where i live, the Netherlands, allthough with a nice garden, the smoke generated by the fire is going to the neighbours. Allthough i didn't got any complaints that day, i would find it annoying if someone else was smoking me out of my own house, so i want to minimize the smoke.

I can recall from Ray Mears' series that smoke generally is generated when you put something wet on top of the fire or when it is not burning cleanly. I used dry paper which sat indoors for a few weeks. I assume regular printed paper is not really the way to go because of the chemicals the industry is using to make the paper. Not to mention if there will be any toxication if i burn a lot of paper.

Looking for other fuels, wood or gas (or something similar), i don't really want to use the wood for making the fire since that's what's making the charcoal in the first place. I don't want to 'toy' with liquid fuels... well, i just don't feel comfortable with that. So imo, i have to stick with the paper i have for making the charcoal.

So, my question, any tips on keeping the smoke contained, minimized, eliminated or anything else that is helpfull is greatly appreciated.



For the record, my interest in Terra Preta started when i saw the documentary Horizon - The Secret For El Dorado. I never actually did something with it, untill a while a go i got interested in growing food myself because that kind of experience could be very helpfull.

[freeztar]

Hey Siggy,

If you can seal your container and run a pipe from it, then you could route the smoke into a tub of water. This should cut down on the smoke and you may be able to collect some of the smoke constituents from the water.

[TerryPradha]

Originally Posted by mjodvis

.... I've read numerous places about the remarkable (indefinite?) amount of time that charcoal will remain sequestered in the soil, continuing to replenish soil nutrients with microbial help. This got me thinking about the effects that earthworms might have on the amount of charcoal in the soil. Are there any data on earthworm consumption of charcoal in the soil? And, if so, does the charcoal become something else after passing through an earthworm, or is it still charcoal?


Thanks for any elucidation.

mjodvis

As I was reading through the newbie thread and I found this question, that I had wondered about myself.

I was thinking in the context of a worm bed to provide adsorption to newly charred chunks. Also if it was in an actively composting compost pile.

Has much been done to figure out the best ways to prime charcoal? By priming, I mean filling the condos with the 'wee beasties' and nutrients.

I appreciate for any ideas.

[Michaelangelica]

Terry
This will happen naturally over time.

You could try soaking the charcoal in a liquid compost or cow poo and water, or water and sugar, or water and a little soluble fertiliser.Grind up the char as fine as you can.

These are just educated guesses that might get your housing estate filled with rent paying residents a little quicker.

[TerryPradha]

Time. That's what I was afraid of
Time and patience. Oh, well.

Thanks for the reply. It helps me sense that I am on the right track, by soaking.

Has anyone had any extraordinary results by growing stuff in char?
That would be a fun thread.

[Michaelangelica]

Originally Posted by TerryPradha

Time.

Has anyone had any extraordinary results by growing stuff in char?
That would be a fun thread.

1 have had so called, annual or bi-annual, parsley last 4 years.

Sound like a good idea for a thread. Start it!