Terra Preta - The parent thread which started it all

[Philip Small]

I thought the retort method used lots of feedstock.

 

I place the retort directly on my BBQ briquets after the steaks finish cooking. I could probably get by with a tad fewer briquets if it was just the steak. A downside is that it only works well when there isn't a cold wind blowing. Hot afternoons best. I expect your in-vessel combustion method isn't quite so limited.

[Philip Small]

Where's the blog Philip?

M

 

Back40's blog.

 

My blog.

[Philip Small]

created by the pyrolysis process is the real challenge.

 

I would love to be BBQing on an inverted downdraft gasifier. A BBQ retrofitted to make charcoal instead of burning it would be a kick. I'm looking fo a Weber Smoky Joe 14.5 inch....

[malcolmf]

Good post Philip, well worth building on.

 

I even emailed Dr. Lehman enthusiastically about glomalin a few weeks ago, thinking to pull my thoughts together on it for a blog post. He was not unaware of the rationale. His entirely neutral response reined me in a bit.

I expect he is on the case but unwilling to say anything until he is safely published. Glomalin drives a coach and horses through much previous TP research, because its effects are so directly relevant that if not factored in, other results are, well, flaky. Give the man time.

 

it's got to be more complicated than just AMF kicking up their glomalin production

Certain to be true but is it important? Review what we know:

1. Charcoal massively increases AMF growth, and is used extensively for this purpose in Japan. E.g. Saito & Marumoto (2002) 'Inoculation with arbuscular mycorrhizal fungi: the status quo in Japan and the future prospects', Plant and Soil 244(1-2), pp. 273-279.
   
2. AMF inherently produce copious amounts of glomalin (Driver et al (2005) 'Characterization of glomalin as a hyphal wall component of arbuscular mycorrhizal fungi', Soil Biology & Biochemistry 37(1), pp. 101-106). This glomalin is recalcitrant and persists long after the hyphae have died.
   
3. AMF are ubiquitous and are productive in tropical forest soil (Lovelock et al (2004) 'Soil stocks of glomalin produced by arbuscular mycorrhizal fungi across a tropical rain forest landscape', Journal of Ecology 92, pp. 278-287).
   
4. Fire does not reduce AMF the way it does other fungi, leaving them as the dominant group for up to 15 years after a burn (Treseder et al (2004) 'Relationships among fires, fungi, and soil dynamics in Alaskan Boreal Forests', Ecological Applications 14(6), pp. 1826-1838). Terra preta soils were prabably continually burned during formation (Hecht in Amazonian Dark Earths).
   
5. Glomalin forms water-stable soil aggregates (Rillig et al (2002) 'The role of arbuscular mycorrhizal fungi and glomalin in soil aggregation: comparing effects of five plant species', Plant and Soil 238(2), pp. 325-333).
   
6. Water-stable aggregates of a similar size to those characteristic of glomalin bind and protect soil components (Teixera & Martins in Amazonian Dark Earths). This accounts for many of the properties of Dark Earth soils: stability; water retention; carbon retention; nutrient retention and reduced leaching; reduced CH4 and N2O emissions.
   

Perhaps you have heard of Occam’s Razor, or of Einstein’s “smallest possible number of hypotheses”? The important properties of terra preta do not need bacteria to explain them. Bacteria work with AMF (Rillig et al (2006) 'Phylogeny of arbuscular mycorrhizal fungi predicts community composition of symbiosis-associated bacteria', Fems Microbiology Ecology 57(3), pp. 389-395), so as you say the reality will be found to be nonlinear, multi-staged, complex and inter-connected, but they aren’t needed as independent agents.

there are pitfalls to fungi as an explanation for TP's self-replication once it has reached its full expression. By then the pH has come up, not so great for the fungi. By then the phosphorus levels have come up, not so great for mycorhhyzal mutualism.

Self-replication of terra preta is reported by Amerindians but is there any scientific evidence for it? It seems to be one of several questionable beliefs (German in Amazonian Dark Earths), in this case perhaps based on Dark Earth’s rapid recuperation under fallowing. Another such belief is that TP does not lose fertility or break down. It most definitely does if not maintained properly (German again).

 

pH up? The mean pH of terra preta is 5.7, and of terra mulata 5.3 (Kämpf et al in Amazonian Dark Earths), higher than the awful common soil but nowhere near suppressing fungi.

 

Phosphorus up? The high P (and Ca) levels in terra preta are believed to be original, from the debris of habitation, not accumulated. They are reported to be the main features distinguishing terra preta from terra mulata, apart from the colour, which is probably due to bacterial decomposition of the debris but has no known beneficial effects. Terra mulata has low P and shows that P does not “come up” in Dark Earths. A useful hypothesis: more glomalin will be found in TM than in TP.

 

I had hoped that there was no link between TP and glomalin, because then we’d have two weapons against carbon dioxide instead of one. But the scientific evidence is too compelling for me right now. Nevertheless, I cling to the hope of a pleasant surprise when independent glomalin assays of Dark Earths are published.

 

M

[Philip Small]

Review what we know:

 

Much appreciated, and certainly helps me as I wrestle with these concepts.

[Michaelangelica]

You are right, David, they didn't. Nor did they bother spading it in. Recent thinking (Lehmann et al's Amazonian Dark Earths) is that Terra Preta, black earth, accumulated from burned waste from cooking fires and trash heaps around habitation, while Terra Mulata, brown earth, accumulated from in-field burning. M

Sorry could you give a page reference for that?

My understanding was the charcoal was very fine in ADE,Terra preta?

[Michaelangelica]

This may be of interest

If glomalin stores 1/3 + of the world's carbon. . .?!!!!!!

 

Glomalin on the Web

Glomalin hiding place for a third of the world's stored soil carbon

Agricultural Research, Sept, 2002 by Don Comis

A sticky protein seems to be the unsung hero of soil carbon storage.Until its discovery in 1996 by ARS soil scientist Sara F. Wright, this soil "super glue" was mistaken for an unidentifiable constituent of soil organic matter.

Rather, it permeates organic matter, binding it to silt, sand, and clay particles.

Not only does glomalin contain 30 to 40 percent carbon, but it also forms clumps of soil granules called aggregates. These add structure to soil and keep other stored soil carbon from escaping.

As a glycoprotein, glomalin stores carbon in both its protein and carbohydrate (glucose or sugar) subunits.

Glomalin hiding place for a third of the world's stored soil carbon Agricultural Research - Find Articles

 

*******************************************

 

WASHINGTON - A sticky protein shed by fungi living on plant roots is responsible for absorbing and storing sizable amounts of the carbon dioxide pollution linked to global warming, U.S. Agriculture Department scientists said.

 

The protein, glomalin, glues soil particles and organic matter together which stabilizes soil and keeps carbon from escaping into the atmosphere.

Planet Ark : Rich soil good for trapping carbon dioxide - study

 

***************************************************

Charcoal in soil acts as a substrate for fungi which secrete a > glue, glomalin, that binds soil particles, water and nutrients together, so > the soil work far better. The charcoal is not consumed, so this process is > carbon negative, but Glomalin accounts for 27% of the carbon in soil, so > adding carbon to soil as charcoal causes yet more carbon to be sequestered.

Dr. Evans Blog » 2006 » December » 07

 

 

*****************

 

 

In 1996, Dr. Sarah Wright and colleagues at the USDA's Agricultural Research Service isolated a glycoprotein called glomalin that literally "gums up" the soil rhizosphere (the interface between soil and plant roots) with carbon fixed from the atmosphere. The compound is produced by common soil fungi called mycorrhizae that frequent the roots of many crops.

When Wright removed glomalin from soil samples, the result was a lifeless mineral powder. The soil had lost its tilth - the substance that conveys texture and health. She had inadvertently discovered the fundamental factor of soil welfare, elusive for over 10,000 years. Humic acid, previously thought to be the main contributor to soil carbon, could muster only a tiny percentage of glomalin's carbon-storing capacity in the field.

Another extraordinary finding was that elevated carbon dioxide levels encouraged mychorrizae to work overtime. Working with a consortium of scientists from UC-Davis and Stanford, Wright simulated CO2 projections for the year 2100 and observed ramped up glomalin production, with thriving fungi. . . .

. Most importantly, the USDA research demonstrated glomalin's tendency to buildup in the soil. Intensively farmed fields consistently leveled off at 0.7 mg of glomalin per gram of soil, while undisturbed plots saw an increase from 1.3 to 1.7 within three years. In hindsight, the Dust Bowl of the 1930's wasn't a casualty of overfarming, but overplowing.

. .

I hadn't known, or had forgotten, that mycorrhizae harbor and sustain soil microbes. It makes sense given their habits of transporting phosphorous, nitrogen and carbon around underground - the "dirt internet" so to speak. When mycorrhizae thrive, so does eveything else.

Muck and Mystery: Glomalin Critics

 

******

 

Carbon Coalition Against Global Warming

Work in the area of ammending soil with bio-char and, separately or in combination with bio-char, promoting mycorrhyzal fungi to produce glomalin seem both very promising in terms of the fundamental science. Both are fairly recent discoveries with huge implications. Hopefully we have a few more rabbits to pull out of the living soil hat.

Carbon Coalition Against Global Warming: February 2006

 

 

***********************************************************

No one has mentioned worms?

I have seen one estimate of phylum Nemata saying that if those in 1sq.m. of soil (any soil, not especially Terra preta) were stretched 'head to toe' they would stretch to Mars.

Nematodes are the most numerous multicellular animals on earth.

The vast majority of species encountered are poorly understood biologically. There are nearly 20,000 described species classified in the phylum Nemata.

We know so little about soil fungi. We have named about 10% of the life in the soil

 

The S.A.Indians say Terra preta soil "grows".

I am inclined to believe them. They have been right about everything else.

SEE

ET 9/98: First-ever estimate of total bacteria on earth

"Another important part of the study was an estimate of carbon content in bacteria. Carbon, of course, is a crucial element in numerous natural processes, so knowing the amount of it could contribute substantially to knowledge of carbon cycles.

Scientists assume that carbon in the bacteria that live in soil and subsurface takes up about one-half of their dry weight.

The team thus found that the total amount of bacterial carbon in the soil and subsurface to be yet another staggering number, 5 X 10**17 g or the weight of the United Kingdom.

 

Rather surprisingly, the group at Georgia found that the total carbon of bacteria is nearly equal to the total carbon found in plants.

The inclusion of this carbon in global models will greatly increase estimates of the amount of carbon stored in living organisms"

********************************************************************

[davidgmills]

Sorry could you give a page reference for that?

My understanding was the charcoal was very fine in ADE,Terra preta?

 

I think he is saying that charcoal breaks down into fine particles over time and that is the thinking now.

 

That seems to be what I am observing, as I am not attempting to go to great lengths to pulvarize my charcoal.

 

Not having found a good means of pulvarizing the lump charcoal I buy from Lowes, (bought two more bags today) I have just gone to spading it in the ground. Maybe one day I will rent a tiller, but I have my doubts as to how well a tiller would even work. I have had to take a pair of pliers to the lumps in order to get them into small fragments. I don't see how a tiller would do anything more than throw them around.

 

I feel confident that this lump charocoal I buy is very good quality, after having made my own. Charcoal is harder to break up than one might think.

[Michaelangelica]

I think he is saying that charcoal breaks down into fine particles over time and that is the thinking now.

 

Not having found a good means of pulvarizing the lump charcoal I buy from Lowes, (bought two more bags today) I have just gone to spading it in the ground. Maybe one day I will rent a tiller, but I have my doubts as to how well a tiller would even work. I have had to take a pair of pliers to the lumps in order to get them into small fragments. I don't see how a tiller would do anything more than throw them around.

Thanks

Why couldn't the Brazilian natives ground up the charcoal as they would have ground grain?

 

I leave mine in the bag and thump it with a brick. -Although was it erich who suggested driving over it with a car?- (I was using coconut charcoal that appeared re-constituted.) This works fairly easily. I sometimes use a mortar and pestle as well.

The Japanese use bamboo charcoal up to 5mm

 

From what I have read not-tilling the soil encourages more fungal and perhaps bacterial growth.

[Michaelangelica]

Potential of carbon sequestration by carbonizing wood residue from industrial tree plantation as a Clean Development Mechanism project in the Kyoto Mechanism

ORAL PRESENTATION C

[Michaelangelica]

The Japanese are way ahead of the game

Energy with Agricultural Carbon Utilization Symposium, Georgia

 

Potential of carbon sequestration

carbonizing wood residue

tree plantation as a Clean Mechanism project in

 

Okimori,Y.

(KANSO)

Yamanaka,

Power)

 

Charcoal production can roughly be classified into two categories.

1) Carbonization by the auto thermal process, which includes many traditional and simple methods (FAO 1987).

2) Carbonization represents industrial mass production methods utilizing external heating, which requires fossil fuel (FAO 1985).1) Carbonization by the auto thermal process, which includes many

traditional and simple methods (FAO 1987).

2) Carbonization represents industrial mass production methods

utilizing external heating, which requires fossil fuel (FAO 1985).

Taking into account applications in developing countries, and the participation of the local people;a low cost, easier and simpler method is preferable.

Taking into account applications in developing countries, and the

participation of the local people; a low cost, easier and simpler method is preferable.

Tin drum, Hume pipe and Built-up brick kiln: forest residue

-The furnace materials are inexpensive, conveniently purchased.

-To enable the participation of local people, preventing fires at forest sites.

Tin drum, Hume pipe and Built-up brick kiln : forest residue

- The furnace materials are inexpensive, conveniently purchased.

- To enable the participation of local people, preventing fires at forest sites.

Flat kiln: Pulp mill -Bark, woodloss, chip dust

-Often adopted in barks and wood from chip mills and sawmills inJapan and also in Indonesia.

-Easily operated and maintained, But careful control is requiredto prevent the outbreak of fire.

Flat kiln : Pulp mill - Bark, woodloss, chip dust

- Often adopted in barks and wood from chip mills and sawmills in Japan

and also in Indonesia.

- Easily operated and maintained, But careful control is required to prevent

the outbreak of fire.

 

Charcoal production can roughly be classified into two categories.

1) Carbonization by the auto thermal process, which includes many traditional and simple methods (FAO 1987).

2) Carbonization represents industrial mass production methods utilizing external heating, which requires fossil fuel (FAO 1985).1) Carbonization by the auto thermal process, which includes many

traditional and simple methods (FAO 1987).

2) Carbonization represents industrial mass production methods

utilizing external heating, which requires fossil fuel (FAO 1985).

Taking into account applications in developing countries, and the participation of the local people;

-->a low cost, easier and simpler method is preferable.

Taking into account applications in developing countries, and the

participation of the local people;

--> a low cost, easier and simpler method is preferable.

Tin drum, Hume pipe and Built-up brick kiln: forest residue

-The furnace materials are inexpensive, conveniently purchased.

-To enable the participation of local people, preventing fires at forest sites.

Tin drum, Hume pipe and Built-up brick kiln : forest residue

* The furnace materials are inexpensive, conveniently purchased.

 

* To enable the participation of local people, preventing fires at forest sites.

Flat kiln: Pulp mill -Bark, woodloss, chip dust

 

-Often adopted in barks and wood from chip mills and sawmills inJapan and also in Indonesia.

-Easily operated and maintained, But careful control is requiredto prevent the outbreak of fire.

 

* Often adopted in barks and wood from chip mills and sawmills in Japan

and also in Indonesia.

- Easily operated and maintained, But careful control is required to prevent

the outbreak of fire.

[malcolmf]

Sorry could you give a page reference for that?

My understanding was the charcoal was very fine in ADE,Terra preta?

Teixera & Martins, p271 "These horizons are identified by the dark matrix colours of the top layers, and often by the presence of potsherds, lithic artefacts and charcoal pieces"

Hecht, p360-1, describes present day debris disposal which would result gradual accumulation of char of all sizes, from hearth debris, "burn" middens, and occasional burns of the larger spoil heaps behind houses to deter dogs and vermin.

Your understanding may result from the way soil analysts classify "fractions". The "gravel" fraction is particles above 2mm, while the "soil" fraction is particles below 2mm. You rarely see analysis of gravel fractions, and this seems to be true of the TP literature. The TP soil fraction would contain fines (the powder you get when char is produced) and pieces crushed over the centuries by burial. I guess the latter would predominate.

 

M

[malcolmf]

If glomalin stores 1/3 + of the world's carbon. . .?!!!!!!

Care please. That's soil carbon. Also the carbon in glomalin molecules is fairly insignificant (4-5% of total soil C at best) compared to the carbon trapped in glomalin-based aggregates. Hence "hiding place" in the USDA article's title. It is the aggregates that matter, just as it is aggregates (whether they turn out to be glomalin-based or not) that matter most to terra preta's properties.

 

Much of the other 2/3 is in humin (not same as humic acid), which roughly translates as stuff we know is decomposed organic matter but have no idea of its detailed origins. There may well be another couple of glomalins (in terms of importance) waiting to be discovered in humin formation.

 

Another extraordinary finding was that elevated carbon dioxide levels encouraged mychorrizae to work overtime. Working with a consortium of scientists from UC-Davis and Stanford, Wright simulated CO2 projections for the year 2100 and observed ramped up glomalin production, with thriving fungi.

This is out of date now, having been based on a large one-off expeirmental increase in CO2. More realistic gradual increases do not have a significant effect. (Klironomos et al (2005) Nature 433(7026) pp.621-4)

 

No one has mentioned worms?

The bodies of living things (worms, bacteria, mycorrhizae, etc) contribute a lot less than 1% of total soil carbon. (Rillig et al (2001) 'Large contribution of arbuscular mycorrhizal fungi to soil carbon pools in tropical forest soils', Plant and Soil 233(2), pp. 167-177. Their role is more to make soil a dynamic environment, and in so doing to release global warming gases from it.

 

The S.A.Indians say Terra preta soil "grows". I am inclined to believe them. They have been right about everything else.

I am not, and no they haven't. Laura German catalogues a series of highly variable and sometimes mistaken beliefs in her chapter in Amazonian Dark Earths, a couple of which I mentioned in my response to Philip. Indeed, what have they been right about? What else besides the garbage disposal and land management strategies that produced dark earths? And in the case of terra preta (rather than mulata) the researchers are divided as to whether that was intentional. Until evidence of soil growth is produced, I think it more likely to be a misinterpretation of strong recovery under fallowing.

 

M

[Michaelangelica]

Care please. That's soil carbon. Also the carbon in glomalin molecules is fairly insignificant (4-5% of total soil C at best)

 

Much of the other 2/3 is in humin (not same as humic acid), which roughly translates as stuff we know is decomposed organic matter but have no idea of its detailed origins. There may well be another couple of glomalins (in terms of importance) waiting to be discovered in humin formation.

 

This is out of date now, having been based on a large one-off expeirmental increase in CO2. More realistic gradual increases do not have a significant effect. (Klironomos et al (2005) Nature 433(7026) pp.621-4)

 

The bodies of living things (worms, bacteria, mycorrhizae, etc) contribute a lot less than 1% of total soil carbon. (Rillig et al (2001) 'Large contribution of arbuscular mycorrhizal fungi to soil carbon pools in tropical forest soils', Plant and Soil 233(2), pp. 167-177. Their role is more to make soil a dynamic environment, and in so doing to release global warming gases from it.

 

 

I am not, and no they haven't. Laura German catalogues a series of highly variable and sometimes mistaken beliefs in her chapter in Amazonian Dark Earths, a couple of which I mentioned in my response to Philip. Indeed, what have they been right about? What else besides the garbage disposal and land management strategies that produced dark earths? And in the case of terra preta (rather than mulata) the researchers are divided as to whether that was intentional. Until evidence of soil growth is produced, I think it more likely to be a misinterpretation of strong recovery under fallowing.

 

M

This is out of date now, having been based on a large one-off expeirmental increase in CO2. More realistic gradual increases do not have a significant effect. (Klironomos et al (2005) Nature 433(7026) pp.621-4)

What do you mean by this?

The bodies of living things (worms, bacteria, mycorrhizae, etc) contribute a lot less than 1% of total soil carbon.

No I don't think so.

I will get back to you with some sums

Glomalin, a recently discovered major component of soil organic matter, stores about a third of the world's soil carbon, offsetting industrial

pollution. This is according to a recent collaborative study by scientists

with the Agricultural Research Service and the University of Maryland

(U-MD) at College Park. The study was partially funded by the U.S.

Department of Energy.

 

The study was done by Kristine A. Nichols, a U-MD soil science Ph.D.

candidate and technician at ARS' Sustainable Agricultural Systems

Laboratory in Beltsville, Md., along with colleagues Sara F. Wright and E.

Kudjo Dzantor. Wright, an ARS soil scientist, discovered glomalin in 1996,

and Dzantor is a U-MD soil scientist.

 

Glomalin is a sticky protein produced by root-dwelling fungi and sloughed

into soil as roots grow. By gluing soil particles and organic matter

together, it stabilizes soil and keeps carbon from escaping into the

atmosphere. In an earlier study, Wright found that glomalin serves as a

corrective to global warming because it increases with carbon dioxide

levels.

[organicviticulture] FW: Glomalin, the Unsung Hero of Carbon Storage

 

Large contribution of arbuscular mycorrhizal fungi to soil carbon pools in tropical forest soils

 

Untitled

 

The Soil Makers

1.1 A Brief Look at Soil Zoology

The Fundamental Decomposers

Bacteria, 6 to 10 million per cm2 , or 3 500 kg per acre

Fungi, 1 to 2 km of hyphae per cm2 up to and more than 1000 species in a woodland, about 90% of all material produced by plants is broken down by decomposers

 

 

Pedators and Secondary Decomposers

 

Protozoa, feed on bacteria and fungi

10 million per m2 or

Amoeba a million per gram of soil

Ciliates ten thousands per gram of soil

or

3 grams per m2 in grassland soils

20 grams per m2 in woodland soils

 

Nematodes (round worms), feed on bacteria, fungi, protozoa and plant roots

10 million per m2 in grassland soils

30 million per m2 in woodland soils

or

1 gram per m2

 

Enchytraeids (pot worms) feed on dead plant material

300 000 m2 in moorland soil

200 000 m2 in grassland

or

50 and 35 grams m2 respectively

 

Tardigrades (water bears) 50 to 500 m2

 

Pauropoda 20 to 2000 m2

 

Molluscs (Slugs and Snails) feed on rotting vegetation mostly

 

(there are a couple of carnivorous species which feed on other molluscs)

approx. 15 m2 in grassland soils

approx. 450 m2 in woodland soils

 

Symphyla , feed on fungi,

up to 1000 m2 in grassland soils

up to 3000 m2 in woodland soils

Isopoda (Woodlice) feed on fungi, and dead plant material

500 to 1500 m2 in grassland soils

up to 3000 m2 in woodland soils

 

Diplopoda (Millipedes) feed on fungi, and dead plant material

approx. 20 m2 in grazed grassland

approx. 100 m2 in ungrazed grassland

100+ m2 in woodlands

Chilopoda (Centipedes) feed on insects an other soil arthropods

 

approx. 120 m2 in grassland

150+ in woodlands

Aranaea (Spiders) feed on other arthropods

480 m2 in Moorlands

200 m2 in Pasteur

 

Acari (Mites) feed on everything are very responsive to pH,

 

more at pH 5 than at pH 6, and more in 'Mor' soils than in 'Mul' soils.

100 000 to 600 000 per m2 woodland soils

2 gams per m2

Collembola (Springtails) feed on fungi and bacteria,

 

dependant on soil moisture and pore space.

40 000 to 70 000 m2 in grassland soils

up to 500 000 m2 in coniferous woodland.

Coleoptera (Beetles) up to 2000 to 3000 per m2

in ungrazed grasslands and heathlands, levels are considerably lower in arable soils.

 

Hymenoptera, Ants, live in the soil, feed on other arthropods and plants secretions, nectar etc. important soil movers, the mound building species (wood ants) create large compost piles which often remain after the ants have gone.

 

Gordon's Soil Ecology Page

 

 

 

A critical part of SOM is humus - a very fine, darkcoloured

collection of complex organic molecules.

 

Humus results from the microbial decomposition

of plant and animal material, to the point where

that material has lost all trace of its original

structure. Among the many virtues of humus are

its excellent water and nutrient-holding capacity,

its ability to bind toxins such as heavy metals, and

its role in holding soil aggregates together

.

[Michaelangelica]

This is a good article on charcoal in Horticulture

You may want to go to the original for the references. I have edited them out.

Has anyone used charcoal for propagation? or know of any research on the subject? It may stop 'damping off" and promote germination of some plants. Does anyone know anything about this?

M F C F

 

 

Charcoal is much more widely used and available in the horticulture industry in the UK than here in Australia. They still coppice some forests. The English are also taking a new look at charcoal to replace water holding polymers, perlite and vermiculite.

 

Horticulture

 

Charcoal has been used for horticultural purposes for at least two thousand years,

 

Archaeological research has come up with evidence of charcoal being used as a soil

 

ameliorator in the Amazon basin around the time of Christ. (Do a web search for "Terra preta" for more information-Michael)

 

Green keepers of golf and bowling clubs used charcoal extensively as a top dressing but in recent years this has been substituted by sharp sand, the reason may have been that the demise of the British charcoal industry caused a shortage in supplies of the correct grades. Fine charcoal powder used on lawns (golf) absorbs and eliminates excess amounts of fertilizer and chemicals present in the soil

 

 

Charcoal was widely available from horticultural sundries men up until the late 1960's,

 

for use mainly in bulb fibre where the pots do not have drainage holes. The charcoal was

 

said to keep the compost 'sweet'.

 

 

Orchid growing employs the use of charcoal and specialist growers of carnations and pinks find charcoal to be invaluable.

 

It has been reported that charcoal may act as a means of eradicating moss in lawns.

Trials have been carried out and the results are currently being analyzed

 

Research has shown that growing mediums that have charcoal present, are able to buffer the effects of sporadic watering, by reducing the frequency of watering whilst helping to prevent 'damping off'

 

Charcoal also reduces the leaching of fertiliser in free draining soils as the charcoal's porous carbon structure enables the nutrients to be held for slower release to the plants

.

The inclusion of charcoal in open seedbeds showed that it facilitates the uptake of nutrients. Calcium uptake almost doubles, with significant increases in potassium, magnesium and phosphorus, the pH increases slightly and there is an obvious increase in organic matter.

 

Charcoal has been recommended as part of the treatment for the eradication of a fungal disease, Cylindrocladium that infects Box hedges.

 

Charcoal has proved to be an ideal renewable substitute for perlite and vermiculite, compost additives used to increase aeration and aid drainage, but both finite resources.

 

They reported that the main reason for the decline in the use of horticultural charcoal was that it is a dirty material to handle. If uses can be found that have clear horticultural benefits and minimum handling, then we believe that a considerable market exists. For example, charcoal would make a good additive to grow bags, where the contents aren't handled much and there are problems with erratic watering.

 

The currently favoured water retaining gels are not liked by all growers and there are doubts about how well they actually release the water they have absorbed "Petunias in hanging baskets tested in greenhouses showed no benefits when water-absorbing polymers were used. And plants grown in media containing water-absorbing polymers required watering just as often as plants grown in potting soil containing no water-absorbing polymers.

 

Also, their usable life is limited by the amounts of salt or fertilizers in the soil

 

". Hence, charcoal could be used where watering may be a problem, e.g.

hanging baskets, or where it is hard to change the compost, e.g. in large tubs.

 

Charcoal could be incorporated into locally produced 'green compost'. No further

 

processing, other than simply grading would be required and transport costs would below. We have had preliminary discussions with Scarborough Borough Council about adding fines to their Green Compost and they hope to do some simple trials in hanging baskets.

[RBlack]

To davidgmilss,

 

On breaking up charcoal what I did was get a scrap 2 1/2 ft. long 2x6 and a 3 ft 2x4 and connected them with a barn door hinge and made what is in essence a big nutcracker. I call this the pattented "RBlack Charcoal Cruncher" and it works great. Total cost $2.79 for the hinge and 60 cents for the screws.

 

RB

[davidgmills]

To davidgmilss,

 

On breaking up charcoal what I did was get a scrap 2 1/2 ft. long 2x6 and a 3 ft 2x4 and connected them with a barn door hinge and made what is in essence a big nutcracker. I call this the pattented "RBlack Charcoal Cruncher" and it works great. Total cost $2.79 for the hinge and 60 cents for the screws.

 

RB

 

If you don't mind a little patent infringement, I will have to try that.