Charcoal as a soil additive

[Zeeth]

So I read that charcoal can be the best soil additive you can use, and that If you mix the native soil with some compost, manure, whatever ferts you use and charcoal you will have amazing plant growth. The source I read said that in the Amazon Basin, the natives used charcoal to transform the worlds most infertile soil into the worlds most fertile, terra preta. They said that the charcoal has a lot of surface area, so it absorbs and releases oxygen, which plants roots love. They also said that you can buy a bag of charcoal with no additives (no match lite, quik lite etc.) and crush it up (easier after soaking for a few hours) and add it to your garden soil. They said that 5-10% of the entire soil being charcoal is enough, and that the treatment lasts forever. I just did an experiment of planting 2 seagrapes side by side, both had a hole dug about 3 times the width of the pot. The exception was that while 1 has only native soil (some sort of blue clay mixed with rocks and chalk, musta been from a swamp or something) and the other has about 10% charcoal mixed in. Although sea grape is native to sandy areas and maybe not the best subject to use, it will give a general idea. I'll take a picture hopefully tomorrow, as it's raining at the moment. So has anyone else tried using charcoal as a soil additive? If so, tell us your stories.

Keith

[FRITO]

I was thinking of finding a source to add into potting mix, using it as a replacment for perlite.

I am also interested in more info.

[bayside mike]

I heard that a piece of charcoal the size of a baseball has the surface area of a football field.

Or something like that.

[Zeeth]

  bayside mike said:

I heard that a piece of charcoal the size of a baseball has the surface area of a football field.

Or something like that.

I heard the same thing, or something like that.

[sonoranfans]

charcoal is used as an absorbent for many materials and may also absorb nutrients from fertilizer. It would not be good if those nutrients that were absorbed were critical traces that were withheld from the palm. I think urea and ammonia will also be absorbed, not sure if that means they will then not be available to the roots. A second reference from a reputable source might be a good idea.

[bayside mike]

  Zeeth said:

  bayside mike said:

I heard that a piece of charcoal the size of a baseball has the surface area of a football field.

Or something like that.

I heard the same thing, or something like that.

Maybe someone knows the real numbers.

[Zeeth]

Here's some links:

http://www.npr.org/templates/story/story.p...toryId=89562594

I trust NPR, they usually don't get quacks on there

Also, a nursery who has seen positive results:

http://transectpoints.blogspot.com/2007/02...l-for-real.html

[Gbarce]

I've added charcoaled rice hulls to my potting medium to help lighten and loosen the mix. Works very well with seedlings an is a very cheap alternative to perlite.

The rice hulls are thin and tiny slivers to begin with and burning them into charcoal makes the harder and brittle so they dont compact very easily so they provide a lot of very small airpockets in the soil.

I can't say that I've noticed them depleting nutrients from the soil--taking them away from the seedlings. I should observe that. But I have been using it for the past couple of years and have to say my stuff has been growing fine so far.

Its true charcoal has many micro-fissures - hence the legendary surface area. This is why they have excellent absorption qualities-- often used in air filters to neutralize/absorb bad odors. Because of this large surface area, charcoal is also used in - water filtration. Bacteria grows on the charcoals surfaces-- as water passes through, the bacteria gets to work on the organic material in the water and decomposes it. Since there is such a large area in charcoal, water is spread out and well exposed to the bacteria (which doesn't have a lot of time to do their work before the the water passes them). The water that comes out is "cleaner" in the sense that its now a mixture of water and broken down organic materials that I suppose is easier to absorb by water plants in the aquarium.

Since the charcoal would be static in the soil I WOULD think that it can absord nutrients away from the plants ---BUT I would also think that when plant roots do reach the charcoal the roots can then now harvest the nutrients the charcoal has collected too.

Just my 2 cents.

[amazondk]

We get very good charcoal here. It is lump charcoal with no aditives. Since I always have some leftover charcoal in the grill after I BBQ I started throwing it on the soild in my palm garden in the city. I have a small area planted with palms iin the back yard. Right now it has turned into a container ranch as well. I don´t know if the charcoal is any benefit or not. But, I does give a destination for the left overs. There is a spot in Manaus where they bag charcoal for sale around the city. It is on the side of a street. I am going to see if I can negociate the left over dust from the people to take over to my garden and mix in the soil.

Here is a picture of Terra Preta do Indio. This area was used to plant bananas by the landowner a few years ago. And, it prooduced great bananas according to him.

[Zeeth]

I found this on the wikipedia article on terra preta (talks about how to make it)

"It is important to note that the fresh charcoal must first be “charged” before it can function as a biotope.[33] Several experiments demonstrate that uncharged charcoal can bring a provisional depletion of available nutrients when first put into the soil - until its pores fill up with nutrients. This is overcome by soaking the charcoal for a few weeks (2 to 4 weeks) in any liquid nutrient (urine, plant tea. ...)"

So let's say we get some of our favorite fertilizer that dissolves readily in water, how about miracle gro palm formula, or whatever it's called. You soak your bag of natural charcoal with no additives in a mixture of this miracle gro for 2-4 weeks. After 2-4 weeks you crush up the charcoal (which will be very easy to do after soaking for 2-4 weeks) and mix it with the soil.

Some experiments were done here here:

http://terrapreta.bioenergylists.org/taxonomy/term/174

And they showed that 33% charcoal and 67% soil had better growth than 100% soil, but I read that as little as 5% charcoal would have a positive effect. So if one was to use a mixture of manure, compost, native soil, and charged charcoal, they would have optimum growth in their plants. I have done the 1 experiment already, so I'll do another. I have no control subject, but I think I'll be able to tell if it's growing better than it should. We're buying a foxtail palm in a few weeks, so I'll start soaking some natural charcoal in fertilizer or something, and by the time it's done we should be ready for the palm to be put in. I'll do a mixture like I stated before, with a hole as big as I can make it, and the hole backfilled with the proposed super soil.

How about some others try experiments like these, maybe we can say yes or no as to whether this works. Who wants to participate?

[Palmə häl′ik]

The major components of wood ashes are potassium carbonate (potash)

I think adding spent coffee grounds, plus the charcoal would really kick it up a notch!

Maybe a little seaweed too...

~Ray.

BTW:

I've got some crotons out back that I noticed are totally different colored because I planted them on charcoal from a backyard fire-pits old ashes... They're fire red colored, and have lost all the greens, and yellows that were in the foliage... Stands out like a sore thumb... Just hues of red... I'll get a piccie later...

[Palmə häl′ik]

Here it is, along with the others that're in plain FL dirt. (sand)

[Zeeth]

Hmm... I think it's time for an experiment... This would be a good science fair experiment actually, testing the growth speed of plants in Terra preta vs other soil types. I'll start sometime soon and ring in with the results.

[Kris]

Dear Friends

Here in india we use charcoal for preparing GND/Earth point.And we add lots of edible salt in crystal form...

We use charcoal here since we want the soil to have water retention capability.So If these charcoal are used in pots or soil medium,we must know wheather our climate is dry desert type or wet tropical.

For hot dry climate zones it will be a boon,but for wet zone it will act as super clay.And the plants roots will never dry so those plants & palms like cactus & washy filiferas will eventually rot.

But if one has lots of spare plants(doubles) could very well try and experiment it and give us feedback.But i have no intention of trying this method here.Since i have plenty of clay soil & lots of rainfall.And since iam using chemical fertz,its better excess salts gets washed off periodically.

Love,

Kris

[newnick]

I'm going to do a experiment with 8 Flamethrower seedlings I should be getting in a week or two.

With four of them I'm going to use Miracle Grow Palm and Citrus potting mix, the other four I'm going to mix

25 to 30% fertilizer charged lump charcoal with compost.

I ground up the lump charcoal some before soaking with channel lock pliers.

The cost of these two methods is roughly equal and I'm going to attemt to treat all 8 pots the same after planting. I'll try and post up some more pics as the experiment progresses.

[Justin]

By the way, on this subject, I think anyone on this board would be fascinated to read the chapter from "1491" dealing with how the Amazon tribes made the most of their nutrient deficient soil. They would routinely char part of the nearby forest, then mix the charcoal into the soil. They would cycle this so that at any given time, only a part of the neighboring forest was charred. It was my favorite chapter of the book, but the whole book was quite good.

[Zeeth]

  Justin said:

By the way, on this subject, I think anyone on this board would be fascinated to read the chapter from "1491" dealing with how the Amazon tribes made the most of their nutrient deficient soil. They would routinely char part of the nearby forest, then mix the charcoal into the soil. They would cycle this so that at any given time, only a part of the neighboring forest was charred. It was my favorite chapter of the book, but the whole book was quite good.

Yeah, a show on the science channel about it gave me the idea. Interesting that they cycled the forest so they had less of an impact.

[Palmə häl′ik]

Didja'all see that thing on those locals making charcoal for sale? It's highly illegal in some countries because they can burn down the forest while their making the goods... There are police out there in the jungle looking for the 'charcoal mounds'! No ish. Seriously!

~Ray.

[amazondk]

  Zeeth said:

  Justin said:

By the way, on this subject, I think anyone on this board would be fascinated to read the chapter from "1491" dealing with how the Amazon tribes made the most of their nutrient deficient soil. They would routinely char part of the nearby forest, then mix the charcoal into the soil. They would cycle this so that at any given time, only a part of the neighboring forest was charred. It was my favorite chapter of the book, but the whole book was quite good.

Yeah, a show on the science channel about it gave me the idea. Interesting that they cycled the forest so they had less of an impact.

Regarding the subject of Terra Preta found in many places where I live I do not really think that it had much to do with the forest being nearby. If that is what the book said. The deposits of Terra Preta, such as the one in post 9 that I put on this thread, are found mostly in areas where larger numbers of people lived for a long time. That is thousands of years in many cases. There is evidence of fairly large populations of humans on the Negro River here in Manaus for at least 3 thousand years. In fact the highest quality of pottery comes from some of the oldest artifacts found. The terra preta areas differed from slash burn land use which only uses the area for a short period of time and it cycles back to forest cover. In this case the burned remains of the trees and vegetation provide residues which enhance soil quality on a temporay basis. I frequently throw charred vegetation remains into the planting holes on my land in the country. It seems to help. But, this is not charcoal, it is charred vegetation. Terra Preta was made from a dump in some respects. The communities wastes were deposited there as well as charred vegetation. I was just looking at some terra preta yesterday in the village where I have my country place and the pottery chards are popping out in the soil.

My guess is that original inhabitants here were not concerned at all about their impact on the ecosystem. They just stumbled on a way to better take advantage of their resources and perfected it. Amazonia in 1500 had 10 million people by some accounts. That is half of the population of the Brazilian Amazon region today. I am quite interested in the use of our area in the past and it is a story that is still largely untold.

dk

[Jose Maria]

I agree with amazondk about the origin of "Terra preta", most probably the waste dumps of the people living there...Everything was just dumped right around the living quarters, for centuries.(no plastics, etc... though)

I have seen the same thing in Costa Rica while clearing forest for banana plantations, where there was shrads of pottery,stones and graves.... from thousands of years ago.... the soil was fertile.....the local variety of "Terra preta". The charcoal is not the main reason for the fertility, just happens to be there with other organic ingredients.

Zeeth, to improve your soil, only remove and work the soil only when it is dry, doing this with clay during rain is destroying the soil structure, the porous structure where air and water circulate.

Do not compact soil, make paths to walk on. And as was mentioned before, organic matter of all kinds will improve all aspects of your soil, as long as it is not waterlogged.....

[_Keith]

I added some charcoal to some new beds I was creating this year. To use the Terra Preta style, I burned green wood and extinguished prior to full burn. Our soils are primarily acid here. Sugar cane farmers in this area burn the fields every year to eliminate organic matter which would stay too wet over our wet winters and to provide a good source of potassium for plant growth. It also is an alkaline material that will reduce the acidity of the soil. It is not as effective as limestone, which is used every few years, but it can drastically raise the pH value of a soil. I have noticed that plants, particularly those that prefer a soil on the alkaline side, greatly prefer this treatment, but all plants in general seems to prefer it to. My land is not a sugar cane field, so I do add lime occaisionally.

[Jerry@TreeZoo]

I have a well water system that uses a carbon filter that needs changing right about now. I bet that would be a cheap source for charcoal. These water service companies just throw this stuff away.

[_Keith]

  Jerry@TreeZoo said:

I have a well water system that uses a carbon filter that needs changing right about now. I bet that would be a cheap source for charcoal. These water service companies just throw this stuff away.

Hmmm, charcoal can absord a lot of stuff, it can also relesase it too. I think the secret is to get charcoal ready to accept, not ready to release.

[Jerry@TreeZoo]

If it lasts 1500 years in the soil, only a year in my filter shouldn't be that bad. Let me see what it looks like though.

[Palmə häl′ik]

Keith! Are you doing any tests?

[Zeeth]

*Bump*

The mulch thread reminded me to bring this back up. We never did get the foxtail, so I couldn't do any further experiments, but we will be getting one as soon as the tax refund comes in, so I'll be able to do this when we get it. I did notice that the seagrape planted in the charcoal faired much better in the freezes, which was unexpected.

Newick, any results from your test?

[The Germinator]

I always dump my bar b que ashes into my mix with the tid bits of charcol to boot.

[tropicbreeze]

Fascinating topic, I wasn't on this site when the thread started but it was interesting reading back over all the comments.

About 15 years back I was living in a remote area with very sandy poor soil. One of the strategies I used was to collect charcoal from the seasonal fires that were an annual event. It did make a difference.

Much later I came across references to Terra Preta and researched it as much as possible. Although I've never been to Brazil I've since developed ideas on how the local people there had produced this type of soil.

The property I have now is predominantly a lateritic gravel overlaying a strange yellowish porous subsoil that doesn't hold water but in the wet season is a fine mush. For the past few years I've been collecting charcoal, initially grinding it to a powder. More recently I've worked out where I can collect fine charcoal without having to make the effort to grind it.

There's a few different angles I'm approaching to the use of charcoal. One is through a large compost heap which has a lot of soil and some fine clay incorporated. The compost included palm fronds so I added some urea to promote rapid breakdown.

Another method was digging it in with poor soil and including a lot of organic matter, mainly leaves. The idea is to let the worms do the work of mixing it all up.

The final way is to put it in large containers and fill those with liquid fertilisers, mainly seaweed or fish emulsion. After only a day or so it's used in potting mixes or just incorporated in the ground when plant things.

I'm very pro-charcoal, but don't want to turn this post into a long winded thesis. I'm going to persist with what I've started even though I don't have the three odd thousand years that the Amazonians developed theirs in. So one thing for sure, it's going to keep me off the streets for a while.

[Wai`anae Steve]

  On 8/16/2009 at 11:54 PM, Zeeth said:

Here's some links:

http://www.npr.org/templates/story/story.p...toryId=89562594

I trust NPR, they usually don't get quacks on there

Also, a nursery who has seen positive results:

http://transectpoints.blogspot.com/2007/02...l-for-real.html

Keith,

Don't believe everything you hear on NPR. They are pushing Global Warming...are you worried your palm are going to get fried by to much heat? :-) Or by freezing the next winter?

[Zeeth]

  On 4/1/2010 at 12:36 AM, Wai`anae Steve said:

  On 8/16/2009 at 11:54 PM, Zeeth said:

Here's some links:

http://www.npr.org/templates/story/story.p...toryId=89562594

I trust NPR, they usually don't get quacks on there

Also, a nursery who has seen positive results:

http://transectpoints.blogspot.com/2007/02...l-for-real.html

Keith,

Don't believe everything you hear on NPR. They are pushing Global Warming...are you worried your palm are going to get fried by to much heat? :-) Or by freezing the next winter?

I like NPR

Except those money drives... they start get annoying after the 5th week straight of nothing but telling me why I should donate...

[Wai`anae Steve]

  On 8/23/2009 at 7:21 PM, Justin said:

By the way, on this subject, I think anyone on this board would be fascinated to read the chapter from "1491" dealing with how the Amazon tribes made the most of their nutrient deficient soil. They would routinely char part of the nearby forest, then mix the charcoal into the soil. They would cycle this so that at any given time, only a part of the neighboring forest was charred. It was my favorite chapter of the book, but the whole book was quite good.

Sorry for "budding" in on the "old" topic, but...It's a well known fact that tropical rainforest soils are poor in nutrients. That is why the natives world wide that lived/live in these area practice a type of agriculture known as "Slash and Burn". They would cut down a section of jungle and when it was dried out enough to burn, they would torch the cuttings. When the fire was out and cooled down the remaining "stuffs" would be dug into the soil. This would last a few years and then they would move on to another spot and repeat the process. When enough years passed and the jungle took over the first plot they would cut it down again and start all over.

Another thing that makes jungle soil fertile is the constant supply of compostable matter droping down and rotting in the moist heat. But once the forest is burned down and planted they compost nutrients are used up in a few years and the soil becomes "poor". that's why they moved on to another area.

[Zeeth]

  On 4/1/2010 at 12:46 AM, Wai`anae Steve said:

  On 8/23/2009 at 7:21 PM, Justin said:

By the way, on this subject, I think anyone on this board would be fascinated to read the chapter from "1491" dealing with how the Amazon tribes made the most of their nutrient deficient soil. They would routinely char part of the nearby forest, then mix the charcoal into the soil. They would cycle this so that at any given time, only a part of the neighboring forest was charred. It was my favorite chapter of the book, but the whole book was quite good.

Sorry for "budding" in on the "old" topic, but...It's a well known fact that tropical rainforest soils are poor in nutrients. That is why the natives world wide that lived/live in these area practice a type of agriculture known as "Slash and Burn". They would cut down a section of jungle and when it was dried out enough to burn, they would torch the cuttings. When the fire was out and cooled down the remaining "stuffs" would be dug into the soil. This would last a few years and then they would move on to another spot and repeat the process. When enough years passed and the jungle took over the first plot they would cut it down again and start all over.

Another thing that makes jungle soil fertile is the constant supply of compostable matter droping down and rotting in the moist heat. But once the forest is burned down and planted they compost nutrients are used up in a few years and the soil becomes "poor". that's why they moved on to another area.

But they have found that Slash and char doesn't result in the soil becoming poor again, which is how terra preta was made.

[DoomsDave]

  On 4/1/2010 at 12:46 AM, Wai`anae Steve said:

  On 8/23/2009 at 7:21 PM, Justin said:

By the way, on this subject, I think anyone on this board would be fascinated to read the chapter from "1491" dealing with how the Amazon tribes made the most of their nutrient deficient soil. They would routinely char part of the nearby forest, then mix the charcoal into the soil. They would cycle this so that at any given time, only a part of the neighboring forest was charred. It was my favorite chapter of the book, but the whole book was quite good.

Sorry for "budding" in on the "old" topic, but...It's a well known fact that tropical rainforest soils are poor in nutrients. That is why the natives world wide that lived/live in these area practice a type of agriculture known as "Slash and Burn". They would cut down a section of jungle and when it was dried out enough to burn, they would torch the cuttings. When the fire was out and cooled down the remaining "stuffs" would be dug into the soil. This would last a few years and then they would move on to another spot and repeat the process. When enough years passed and the jungle took over the first plot they would cut it down again and start all over.

Another thing that makes jungle soil fertile is the constant supply of compostable matter droping down and rotting in the moist heat. But once the forest is burned down and planted they compost nutrients are used up in a few years and the soil becomes "poor". that's why they moved on to another area.

Terra preta is completely different. It allowed a large population to prosper in one place for a long time.

Of course, all this begs the question of what happened to the people who did all that? Where did they go? Did they succumb to diseases introduced by the Europeans?

Perhaps I'll buy a copy of 1491 and find out . . . .

[Zeeth]

  On 4/1/2010 at 2:01 AM, Dave from So-Cal said:

  On 4/1/2010 at 12:46 AM, Wai`anae Steve said:

  On 8/23/2009 at 7:21 PM, Justin said:

By the way, on this subject, I think anyone on this board would be fascinated to read the chapter from "1491" dealing with how the Amazon tribes made the most of their nutrient deficient soil. They would routinely char part of the nearby forest, then mix the charcoal into the soil. They would cycle this so that at any given time, only a part of the neighboring forest was charred. It was my favorite chapter of the book, but the whole book was quite good.

Sorry for "budding" in on the "old" topic, but...It's a well known fact that tropical rainforest soils are poor in nutrients. That is why the natives world wide that lived/live in these area practice a type of agriculture known as "Slash and Burn". They would cut down a section of jungle and when it was dried out enough to burn, they would torch the cuttings. When the fire was out and cooled down the remaining "stuffs" would be dug into the soil. This would last a few years and then they would move on to another spot and repeat the process. When enough years passed and the jungle took over the first plot they would cut it down again and start all over.

Another thing that makes jungle soil fertile is the constant supply of compostable matter droping down and rotting in the moist heat. But once the forest is burned down and planted they compost nutrients are used up in a few years and the soil becomes "poor". that's why they moved on to another area.

Terra preta is completely different. It allowed a large population to prosper in one place for a long time.

Of course, all this begs the question of what happened to the people who did all that? Where did they go? Did they succumb to diseases introduced by the Europeans?

Perhaps I'll buy a copy of 1491 and find out . . . .

Dave, watch this video

[amazondk]

  On 4/1/2010 at 2:01 AM, Dave from So-Cal said:

  On 4/1/2010 at 12:46 AM, Wai`anae Steve said:

  On 8/23/2009 at 7:21 PM, Justin said:

By the way, on this subject, I think anyone on this board would be fascinated to read the chapter from "1491" dealing with how the Amazon tribes made the most of their nutrient deficient soil. They would routinely char part of the nearby forest, then mix the charcoal into the soil. They would cycle this so that at any given time, only a part of the neighboring forest was charred. It was my favorite chapter of the book, but the whole book was quite good.

Sorry for "budding" in on the "old" topic, but...It's a well known fact that tropical rainforest soils are poor in nutrients. That is why the natives world wide that lived/live in these area practice a type of agriculture known as "Slash and Burn". They would cut down a section of jungle and when it was dried out enough to burn, they would torch the cuttings. When the fire was out and cooled down the remaining "stuffs" would be dug into the soil. This would last a few years and then they would move on to another spot and repeat the process. When enough years passed and the jungle took over the first plot they would cut it down again and start all over.

Another thing that makes jungle soil fertile is the constant supply of compostable matter droping down and rotting in the moist heat. But once the forest is burned down and planted they compost nutrients are used up in a few years and the soil becomes "poor". that's why they moved on to another area.

Terra preta is completely different. It allowed a large population to prosper in one place for a long time.

Of course, all this begs the question of what happened to the people who did all that? Where did they go? Did they succumb to diseases introduced by the Europeans?

Perhaps I'll buy a copy of 1491 and find out . . . .

Dave,

In 1500 AD there were probably anywhere from 5 to 10 million people living in Brazilian Amazonia. There are about 20 million today. And, most of the these people live in cities. Between Manaus and Belem about 4 million of them live. The populations were largely sedentary and lived in sometimes large concentrations along the river banks. Here in Manaus the area was fairly densely populated going back several thousand years. The eurpean contact did two things, 1. it wiped out large populations due to disease, 2. local indigenous populations were aculturated and became what are known as cabocolos today. Terra preta was formed over many years in association with these permanent sedentary populations. It is important to point out that terra preta is not the only fertile soil in Amazonia. The varzea, which is the flood plains of the rivers with muddy waters coming from the Andes mountains are fertile as they are made up of deep deposits of rich soil which is replenished regularly by seasonal floods. Of course you can not use these soils when under water. But, the majority of the year they are usuable and are used today as they were in the past.

As to slash and burn. Yes, the soil thickness in our forest is very small. The trees in the forest cycle nutrients quickly from fallen decomposing material from above back to the top very quickly not allowing time for deep top soils to form. So, when an area is deforested the fertility does not last long. But, if one practices modern agro business techology which is being done in areas soy beans, suger cane, corn, and other crops can and is being grown successfully. Of course this needs industrial fertilizer, soil amendments, etc. And, if managed properly pasture land for cattle can be quite productive. What is used is a system called, piquetes. This system divides the pasture up into small lots where the cattle are confined for a brief time until the grass gets to a point where they cattle are moved to the next lot for it to recover. The cattle are rotated from lot to lot until they get back to the first lot, where the grass has recovered to a usuable height. These areas also need the application of fertilizer, dolomite, etc. along with the use of specific grass varieties with high yield qualities developed for the climate.

As to the actual slash and burn land use, it is not really that people move on to another place normally. They will rotate the area where they farm. That is small farmers will keep using the same areas of secondary forest over and over. They will sometimes cut down the primary forest. But, this from what I have noticed is more to expand their area than anything mostly. Just think about it, it is a lot easier to cut down small trees than big ones. Trees in primary forest are very big, and they are a lot of work to cut, especially if you do not have a chain saw. The areas of secondary forest, called capoeira, are always associated with human populations. And, I think this was no different in precolombian times. My land in the country has been used for thousands of years I am sure. There is no sign of any large trees in the secondary forest or the lots around my place. There are no large stumps. There is also a large area of Terra Preta in the village. And, today this is used as a soccer field in the middle of the village. In fact the grassy area in the picture attached below is over Terra Preta. Paricatuba is a great spot today and I am sure the precolombians thought so as well. There is advanced pottery found in the area dating back at least 3,000 years. In fact the older pottery is the more advanced. There is a big untold stor of the regions human inhabitants. Since there is little stone in the region people lived in houses and used buildings of wood which over time disappeared. The Terra Preta is one thing that remained.

[Tyrone]

Fresh ash has a pH around 10. Be careful using the straight ash if you are on alkaline soils.

Denatured charcoal sounds like it absorbs nutrients, but I bet the plant roots would get it out. Charcoal probably has a great Cation Exchange Capacity stopping a lot of nutrient leaching. I'm going to look into it a bit more now.

Best regards

Tyrone

[tropicbreeze]

  On 4/1/2010 at 8:39 AM, amazondk said:

As to the actual slash and burn land use, it is not really that people move on to another place normally. They will rotate the area where they farm. That is small farmers will keep using the same areas of secondary forest over and over. They will sometimes cut down the primary forest. But, this from what I have noticed is more to expand their area than anything mostly. Just think about it, it is a lot easier to cut down small trees than big ones. Trees in primary forest are very big, and they are a lot of work to cut, especially if you do not have a chain saw. The areas of secondary forest, called capoeira, are always associated with human populations. And, I think this was no different in precolombian times. My land in the country has been used for thousands of years I am sure. There is no sign of any large trees in the secondary forest or the lots around my place. There are no large stumps. There is also a large area of Terra Preta in the village. And, today this is used as a soccer field in the middle of the village. In fact the grassy area in the picture attached below is over Terra Preta. Paricatuba is a great spot today and I am sure the precolombians thought so as well. There is advanced pottery found in the area dating back at least 3,000 years. In fact the older pottery is the more advanced. There is a big untold stor of the regions human inhabitants. Since there is little stone in the region people lived in houses and used buildings of wood which over time disappeared. The Terra Preta is one thing that remained.

  On 4/1/2010 at 9:41 AM, Tyrone said:

Fresh ash has a pH around 10. Be careful using the straight ash if you are on alkaline soils.

Denatured charcoal sounds like it absorbs nutrients, but I bet the plant roots would get it out. Charcoal probably has a great Cation Exchange Capacity stopping a lot of nutrient leaching. I'm going to look into it a bit more now.

Best regards

Tyrone

In Indonesia and New Guinea people who carried out slash and burn agriculture did usually move their place of residence. Materials used for housing didn't last all that long in the climate so they were rebuilding anyway. These days modern building materials are getting into some of these places so there's less need to rebuild.

Charcoal does have a high CEC and plants are able to extract the nutrients. Activated charcoal is better for this than the non-activated, but the latter is still very good. The non-carbon component of ash (the white/grey/etc.) usually has a very high pH as the low pH components of organic matter are more volatile and go up in the smoke of fires. One of the down sides of fresh charcoal is that initially it rapidly absorbs nitrogen and can deplete the soil.

Clay and humus rich soils also have a high CEC, but clays tend to waterlogging, compaction and poor aeration. Humus rapidly breaks down, especially in tropical conditions, allowing nutrients to end up being leached away. It can be very difficult maintaining humus levels in tropical conditions.

Charcoal is quite stable and although in concentration as a fine powder can become quite soggy, it allows for reasonable drainage when mixed with with a porous soil such as mine (lateritic sandy/gravel).

[newnick]

  On 3/31/2010 at 11:28 AM, Zeeth said:

*Bump*

The mulch thread reminded me to bring this back up. We never did get the foxtail, so I couldn't do any further experiments, but we will be getting one as soon as the tax refund comes in, so I'll be able to do this when we get it. I did notice that the seagrape planted in the charcoal faired much better in the freezes, which was unexpected.

Newick, any results from your test?

I haven't seen anything dramatic yet, it's been 7 months so far. The eight plants are basically growing at the same rate so far. I started this experiment kind of late last summer so we'll see if a whole growing season will make a difference.

[Tomw]

  On 4/4/2010 at 6:28 PM, newnick said:

  On 3/31/2010 at 11:28 AM, Zeeth said:

*Bump*

The mulch thread reminded me to bring this back up. We never did get the foxtail, so I couldn't do any further experiments, but we will be getting one as soon as the tax refund comes in, so I'll be able to do this when we get it. I did notice that the seagrape planted in the charcoal faired much better in the freezes, which was unexpected.

Newick, any results from your test?

I haven't seen anything dramatic yet, it's been 7 months so far. The eight plants are basically growing at the same rate so far. I started this experiment kind of late last summer so we'll see if a whole growing season will make a difference.

How about an update? This is a very interesting old thread.

[newnick]

I repotted these last year and lost track of which ones were which. I've got two or three that are doing really well, a few not so good and a few have died.