Terra Preta Recipes and Results

[Moontanman]

Originally Posted by freeztar

If we are talking about the same thing, then it is not native and most certainly invasive.
I would love to see your bonsai swamp trees!
As an ecologist here in Georgia, I enounter bald cypress and swamp tupelo all the time, but of course they're not bonsais.

So, to bring this *wonderful thread* back on-topic, how did you come to the 10% charcoal in the soil mixture? Was it experimentation, or just a guess that worked, or you read it somewhere?

10% just happened to be the amount of charcoal i had when i fiorst started making this stuff so I kept with it. I seldom have much of it so to add more i would have to use either new charcoal or grill type charcoal. I have been thinking of add charcoal grill ash but not to the aquarium soil. Swamp trees are really great in aquaria. They make a very natural looking display. The roots eventually grow into a mat like structure that many fish like to spawn on. My main goal in the aquarium soil is to make a soil that doesn't loose it's ability to grow plants too quickly but then again doesn't pollute the water. It's a fine line between nutrient content and nutrient release.

Michael

[Gerrit]

I'm getting a ton of char from a local pyrolysis plant to put on my garden.

How much char should I put on a heavy clay soil? Is 10% by volume too much? The bulk density of char is only 250kg./cubic meter. I forget the bulk denisty of soil, but it is probably 5 or 6 times that much.

Gerrit

[InfiniteNow]

Originally Posted by Gerrit

I'm getting a ton of char from a local pyrolysis plant to put on my garden.

How much char should I put on a heavy clay soil? Is 10% by volume too much? The bulk density of char is only 250kg./cubic meter. I forget the bulk denisty of soil, but it is probably 5 or 6 times that much.

Gerrit,

You might check here, particularly, Phillip's posts. I'm not sure if it addresses your question or not, but it's a good place to start.

http://hypography.com/forums/terra-p...arbon-how.html

[malcolmf]

I'm worried by the results that include dead or damaged plants after charcoal application. Enough of these reports in the hands of the less favourably inclined could kill terra preta nova stone dead.

Posters have shrugged them off with a "must have been because ...". I think a more scientific approach to finding out why it happened or what prevents it is needed.

Hypothesis: an addition of pure char to soil initially sucks up moisture and nutrients, making them unavailable to plants. (Don't forget: the Amazonians didn't use anything remotely like this method).

Possible experiments:

1. Drench half the char with water before application, half untreated. The water half should not then take up large amounts of dissolved nutrients from the soil.
2. Drench half the char in liquid fertiliser (organic or not) before application, half untreated. Don't apply any of the leftover liquid, so that the effect is limited to what the char absorbed.
3. Plots or pots of identical soil with char additions varying.

Given the long tradition in Japan of char soil amendment, perhaps there are papers from it on precise soil management regimes? What did the Japanese speakers say at Terrigal?

M

[freeztar]

Originally Posted by malcolmf

I'm worried by the results that include dead or damaged plants after charcoal application. Enough of these reports in the hands of the less favourably inclined could kill terra preta nova stone dead.

Posters have shrugged them off with a "must have been because ...". I think a more scientific approach to finding out why it happened or what prevents it is needed.

Hypothesis: an addition of pure char to soil initially sucks up moisture and nutrients, making them unavailable to plants. (Don't forget: the Amazonians didn't use anything remotely like this method).

Possible experiments:

1. Drench half the char with water before application, half untreated. The water half should not then take up large amounts of dissolved nutrients from the soil.
2. Drench half the char in liquid fertiliser (organic or not) before application, half untreated. Don't apply any of the leftover liquid, so that the effect is limited to what the char absorbed.
3. Plots or pots of identical soil with char additions varying.

Given the long tradition in Japan of char soil amendment, perhaps there are papers from it on precise soil management regimes? What did the Japanese speakers say at Terrigal?

M

Those are some valid points, but let's not forget about pH. I would imagine that pH is much quicker acting on the plants than nutrient or water adsorbtion.

[malcolmf]

Originally Posted by freeztar

I would imagine that pH is much quicker acting on the plants than nutrient or water adsorbtion.

A fine imagination, but charcoal sucks in water, including its dissolved nutrients, like a vacuum cleaner. What happens when your houseplants dry out?
This may be a reason why today's Amerindians mulch on top of charred material.

[freeztar]

Originally Posted by malcolmf

A fine imagination, but charcoal sucks in water, including its dissolved nutrients, like a vacuum cleaner. What happens when your houseplants dry out?
This may be a reason why today's Amerindians mulch on top of charred material.

Ok, imagination aside, what happens when you dump a bit of acid on your soil?
I'll answer for you.
The soil becomes more acidic.
What then happens to basic-loving plants?
I'll leave that one to the imagination...

All I am saying is that other factors are involved and we should take them all into account. The charcoal "sucking in water like a vacuum cleaner" is acting as a storage center for said water and nutrients. The plants are able to cling their roots to the char and extract these nutrients and the water with the help of wee beasties. The pH however is not so easily surmounted.

The reason I said "I imagine" is because I do not have any experimental data to back my claim. However, my pH soil probe is in the mail and I'll be doing some experiments on my own shortly. Cheers.

[Gerrit]

Regarding soil chemistry, Dr Van Zwieten said agrichar raised soil pH at about one-third the rate of lime, lifted calcium levels and reduced aluminium toxicity on the red ferrosol soils of the trial.

"Soil biology improved, the need for added fertiliser reduced and water holding capacity was raised," he said. The trials also measured gases given off from the soils and found significantly lower emissions of carbon dioxide and nitrous oxide (a greenhouse gas more than 300 times as potent as carbon dioxide).

Other investigators have noted that the relative neutralizing value (RNV) of char for acidic soils depends on what the char was made from and how it was made. But even at 1/3 the RNV of lime the change would be significant since so much char is used. Those with calcareous soils could not use it unless they buffered the alkalinity, perhaps with sulfur.

from "http://www.garyjones.org/mt/archives/000540.html"

[palmtreepathos]

One of my first char added soil amendments was to a desk plant that was needing a repot. Every few weeks the pathos could be found collapsed from lack of water. So into the mix went some char and some rotted wood mulch and a bit of potting soil. I am not sure of the percentage of char (no science there!) and no fertilizer added before mixing it up. I did do a "miracle-gro" drench right after planting it. The plant became our posterchild for what NOT to do with biochar. It absolutely went into suspended animation for the next year. Not a single leaf.

But on the other hand it has never shown any stress over water shortage, in that whole year and I don't water it very often.

The same thing occurred with an avocado tree that I transplanted from the compost heap, suspended animation until late spring when I did a bit of creative supplementation with deep holes and worm castings and liquid manure tea. now it is lush and healthy.

All of the char added to my organic garden was either mixed with humanure compost or with a fermented vegetation mix as the fertilizer, which seemed to me the closest I could get to what the early terra preta makers might have had available. The garden is wildly successful. Fully half of the garden is new, soil that was under a tree that we had removed, pure red georgia clay, then rotted leaves and the char/mix was added. About two 5 gallon buckets per 14 ft x 3ft raised planting bed. All the beds are fed with homemade organic fertilizer(Steve Solomon's Formula) I make it up and mix in (4-6 inches deep)at seeding and sprinkled on top every couple weeks as heavy growth dictates. Will post a seed starter formula later.

A Better Way to Fertilize Your Garden - Homemade Organic Fertilizer

[Michaelangelica]

Originally Posted by Gerrit

Regarding soil chemistry, Dr Van Zwieten said agrichar raised soil pH at about one-third the rate of lime, lifted calcium levels and reduced aluminium toxicity on the red ferrosol soils of the trial.

Similar results in this paper by christopher steiner in germany
Slash and Char as Alternative to Slash and Burn | Terra Preta

Conclusions
Charcoal is influencing soil quality in manifold ways, most importantly by reducing available Al and reducing acidity. Furthermore, charcoal adds K to the soil and has the potential to reduce N leaching. Charcoal amendments increased the reproduction rate of the microbial population after substrate addition whether the plot was fertilized or not. The effects of charcoal on soil biological, chemical and physical properties are complex, making it difficult to isolate single significant charcoal effects, but added up they caused significantly increased
plant growth and crop production.

More information is needed on the agronomic potential of charcoal, the potential to use alternative biomass sources, and the production of by-products to evaluate the opportunities for adopting a slash and char system. The access to a global C trade mechanism would facilitate charcoal use for soil amelioration and thus would increase C sequestration and create a strong incentive to prevent further deforestation. Both of these actions would help
to mitigate global climate change.

Personally I have had trouble putting char on to acid loving plants like camellias, magnolias, gardenias and even aquilegias (pH 4-8). I do tend to be a bit heavy handed with applying char.
The aquilegias in a small pot strangely almost died, quickly recovered to their previous glory then looked ill again . It was as if the pH initially wet up dramatically, then down, then up slightly again. Now they are on their way to recovery again.
I intend to use my pH testing kit a bit more in future.A little precission measuremnet may have helped with some useful info.- I recommend it to you.
I am a bit haphazard in my approach; the science being overtaken with the enthusiasm of adding a "magic ingredient" to my plants.
Yet there is continuing long term Japanese research programme putting 100g of char per meter, per Tea (camellia) Tree, per year, over the last 4-5 years with (40%?) enhanced growth observed. (They intend to run the research programme for 10 years.)
I wonder if an equivalent amount of lime or dolomite added would archive the same result?