carbon sequestering for your garden and the planet

[400lbsonacubseatspring]

During some research I've been doing on an appropriate technology concept I have been toying with, I came accross something interesting, I'd like to pass along as an Idea/Suggestion/Plea to those of you who garden and farm on any scale at all.

Hundreds of years ago, in Brazil, the first farmland was cleared by burning, as was done in many areas of South America. The actual soil under this forest was an impoverished yellow clay, as is found throughout the world. Because of the rainfall, the wood did not burn completely as was hoped, and the majority of it was reduced to charcoal instead of ash. This charcoal was broken up as well as possible and incorporated into the soil.

Five centuries later, this soil is being sold as "Terra Preta" for use as a potting soil throughout the world (Brazil will sell anything). It's moisture holding ability and beneficial microbe population is first quality, bar none.

The magic here, apparently is the ability of the charcoal, through its micro-pores, to house the beneficial microbial populations, and promote their population's growth.

Attempts at reproducing "Terra Preta" have shown that adding as much as 30% low-temperature produced charcoal(as produced in an open fire-water quenching method), will within 3 years begin to improve the census of beneficial microbes in the soil.

Crop tests in the "newly created" terra preta vs original soil, all other factors the same, show improved growth and drought resistance after 4 years. The great thing, in this case, is that this soil treatment will continue to increase beneficial microbes over the next several centuries, as it mechanically breaks up into smaller and smaller pieces.

Now for the really good news. For every ton of carbon (as charcoal) incorporated into the soil, an additional 5 tons of carbon from the atmosphere is transformed and stored in the soil by the microbes. This replenishes carbon-depleted soils, and sequesters atmospheric CO2 for thousands of years.

Does the burning of wood release co2? yes, but only 20% of what will ultimately be sequestered in the soil by the microbes.

Do you need to add additional nitrogen to help "break down" the charcoal? NO, the charcoal does not breakdown chemically, but rather mechanically, by the activity of the microbes, tilling, freeze/thaw cycles, cub tires, etc.

This is one way we can help get co2 out of the air NOW, improve our crops, and dispose of wood waste appropriately, all at the same time. It's definitely a win-win situation.

Since the average human in the US produces less than a ton of CO2 per year by using automobiles, sequestering a couple of tons of carbon into your garden really can make a difference.

This low-tech technology could also be used under new lawns, flower beds, etc.

Letting wood rot releases its co2 into the atmosphere, with no benefit whatsoever to man or planet. Turning it into charcoal, and incorporating it into your soil benefits both.

[jostev]

Tom, that's kinda what we do, we just burn cardboard...
We put our leftover pumpkins in the garden last year, and this year was our best year, and we never planted anything, just rototilled it... I just rototilled LOL

Thanks for the info Johnny

[beaconlight]

Interesting. I screen my ashes and burn the resulting charcoal lumps. I think I will just spread them with the ashes in the futues or else put them in the garden and the ashes all ove not to over toad the garden.

Bill

[Rudi]

Tom:

That was kind of interesting even though there are parts that are beyond my ken. Some of this stuff also seems to fit in along the lines that I have traditionally sought to incorporate into my 3R philosophy. I have always believed in leaving my land or any land in better condition than when I found it.. and by returning to the earth more than we actually take out..

I use wood primarily to heat my home and firmly believe that it is the most environmentally friendly way to keep warm yet keep emmissions either very low or as close to natural as possible.

Interesting. I screen my ashes and burn the resulting charcoal lumps. I think I will just spread them with the ashes in the futues or else put them in the garden and the ashes all ove not to over toad the garden.

I just spread our stove ashes in the fields... unburned bits and all.. and surprisingly there is a substantial amount of charcoal that is present. I have noticed over the past couple of years that there seems to be an improvement in the aerative properties of the soil as well. Packing is not as dense... Also, tree bark mulch and sawdust have become plentiful, cheap and do offer some conditioning properties as well. Many use these types of conditioners as well to provide additional nutrients and aeration.

The local people here have been using woods ashes for a couple hundred years to help fertilize and rejuvenate soils. Of course other sources of material have been used from fish, seawead and of course your normal bedding/manure mixes.

Kind of interesting too... I have spread ashes in my fields that I do not plow and have for about 18 years... we now seem to have wild blueberrys growing

One thing to keep in consideration though is the crops that you will be planting in those areas... tubers such as potato's and other root type crops tend not to like charcoal or tree bark that is used as mulch, and especially do not like sawdust. So avoid using that type of conditioner when planting root crops....

[400lbsonacubseatspring]

I do apologize if I've gone "too techie" on this. I read over my notes, and just started writing.

I use wood primarily to heat my home and firmly believe that it is the most environmentally friendly way to keep warm yet keep emmissions either very low or as close to natural as possible.

Absolutely, Rudi. Everyone who can, should heat with wood, so long as it's not at the expense of forest. Burning fallen wood, and thinning out trees that have reached the end of their life-cycle is some of the best stuff you can do for the environment. Burning of wood has the same "net" CO2 emissions as the rotting of wood, you get the benefit of warmth, and you're not burning several tons of fossil fuels each year to do so.

Interesting. I screen my ashes and burn the resulting charcoal lumps. I think I will just spread them with the ashes in the futues or else put them in the garden and the ashes all ove not to over toad the garden.

Ashes are about the best natural source of Potash, period. It is difficult to get too much potash in the soil, as it does leech out to lower levels, it is possible, though to raise the PH too high, but adding sawdust or other wood products usually buffers that pretty well.

I just spread our stove ashes in the fields... unburned bits and all.. and surprisingly there is a substantial amount of charcoal that is present. I have noticed over the past couple of years that there seems to be an improvement in the aerative properties of the soil as well.

Rudi, if you have the chance.....super load a small area with charcoal, as I said, up to 1/3 in volume, and in 3 years, it will be the richest soil for miles around. Charcoal itself is relatively inert carbon, so it doesn't change soil PH much at all. Beneficial bugaboos will live in the charcoal, and create a mutually profitable "symbiotic" relationship with your plants, all the while, their little "corpses" are depositing additional carbon into your soil, thereby enriching it for several thousand years.

One thing to keep in consideration though is the crops that you will be planting in those areas... tubers such as potato's and other root type crops tend not to like charcoal or tree bark that is used as mulch, and especially do not like sawdust. So avoid using that type of conditioner when planting root crops....

This is interesting...potatoes dislike wood products, it's true, but they shouldn't mind charcoal by itself, without the accompanying ash. When the guys at Georgia State did the tests with the Terra Preta, one of the researchers mixed a handfull of turnip seeds into a pile of charcoal that they weren't going to use. The topgrowth and hair roots were described as being far in excess of anything anyone had ever seen. The turnips themselves were described as "delicious"....LOL

[Jack fowler]

Deleted

[Don McCombs]

I'm thinking that it may be possible that coal ashes might give a similar result. Best garden I ever had was where the PO of the house had dumped coal ashes for decades. Huge tomatoe plants and lots of tomatoes.

[400lbsonacubseatspring]

I'm thinking that it may be possible that coal ashes might give a similar result. Best garden I ever had was where the PO of the house had dumped coal ashes for decades. Huge tomatoe plants and lots of tomatoes.

Don, Living here in Anthracite Country, where about 1/3 of homes are still heated by coal, it is still commonplace to add coal ash to soil as a soil ammendment. Coal ash contains a lot of trace minerals, which can be beneficial, especially to complex feeders like tomatoes. They also make the soil much easier to till. I remember my grandfather's tomato patch, always planted in the same place, with decades of coal ash dumped into the soil. He always hand-dug it, and the amount of "loft" attained was amazing....8 to 12 inches higher when dug than before. He had Roma tomato plants that reached 8ft high every year, something I have since been unable to do. He also used dried chicken manure as a fertilizer, though, which I since learned can be as high in nitrogen as 50%., although typically its analysis is more like 30-8-8.

There are no carbon-enriching properties to coal ash, however, since most all of the carbon has been burnt out, and what is left is still coal, which is toxic enough to microbes to prevent their habitation.

To get the CO2 out of the atmosphere, where it is causing harm, and back into the soil where it belongs, and will enrich our soil and garden productivity, it needs to be charcoal from plant material.

I'm no tree-hugging environmentalist, but the recent studies about climate change and soil carbon depletion are looking pretty darn grim. This is one way we are able to help.

[cowboy]

Wow amazing I never thought about it. I know that soap was made from lye which came from water run through ashes and was very castic untill mixed down or somthing like that. And I have been dumping my ashes on weed paches trying to kill them. But I haven't been here long enought Or thought I knew what I was doing and did not pay any real attenson to to that blind spot right in front of my nose. But I will be paying attension this next year.

[400lbsonacubseatspring]

. I know that soap was made from lye which came from water run through ashes and was very castic untill mixed down or somthing like that.

My Great Aunt and Uncle who lived next door to me as a boy made their own lye for soap. They'd only make soap once a year, but it was quite a production. They'd save up all their wood ashes from the kitchen stove until they had about 3 bushel full. Then they had an old crock, especially made for lye leaching, that they'd pack full of gravel and straw on the bottom, and fill with ashes. Rainwater was poured through this 5 times through, and then the water was put aside. They'd repeat this until all the ashes were processed. When finished, the ash-water had to be boiled down to create the lye in sufficient strength. It was strong enough when an egg floated enough to expose an area as big as a quarter This was usually a reduction in volume by 80% or so. They had a special enameled washtub and wooden spoon for the soapmaking process, as using it for anything else would be poisonous.

To this, they added in quantity which I do not remember, saved cooking fat from the whole year, re-rendered, so it wouldn't be rancid-smelling, some fresh lard from the farmers, and a solution of rock salt and water, and what was formed at the top of the tub was a nice layer of greyish-white rock-hard soap, that they'd cut into blocks and use to do dishes or grate for laundry detergent in the wooden tub washer that was agitated by hand-cranking a flywheel, a job I relished when I was 8.

It also took the pain out of bee-stings rather nicely, and I'd always run to their house when I'd get stung.

They bought "Dial" to take baths and wash their hands with....LOL

[beaconlight]

Did a search on Terra Preta. Quite interesting. I most enjoyed the part where the locals mine it but leave about 1/3 the thickness and it regenerates. No more charcoal screened out, just nails and other metals.
Cornell, NYS Land grant college has some studies on it too.

Bill

[Russell F]

Real good stuff Tom, it's really got me thinkin, which usually ends in disaster or a hospital vist...

I found this on the net and thought it would go well with this. It's kinda a higher tech way to make charcoal. Not sure how well it'd work, but it looks pretty simple.

http://www.twinoaksforge.com/BLADSMITHI ... ARCOAL.htm

Russell

[beaconlight]

Looks interesting. With those barrels with the lids it is easy to load and unload.

Bill

[400lbsonacubseatspring]

Russell,

That is probably about the most carbon efficient system I've seen for producing charcoal. And it's precisely the right type. All you'd need to do then would be crush it somehow (hammermill or woodchipper, i'd venture to guess), and you'd be set. It would be simple to make that system more robust as well, simply lining the walls with refractory and providing a chimney would do it. Maybe add a large piece of steel as a front door. S-P-F scrap from construction would be a marvelous source of wood feedstock.

As a starter fire, you could burn virtually any unwanted material, such as trash, if you are allowed, as the container would be closed, in essence, or cardboard, or even unwanted tree branches.

In a system like this (pyrolysis), you are reserving 80% of the carbon value of the wood, while driving off the volatile compounds. So:

Aside from whatever you use to fuel the starter fire, you are locking up 80% of the carbon virtually forever (unless you plan on burning it). Charcoal is 99% chemically inert, and hence will never decompose into greenhouse gasses.

So, here's the math on how much good it does:

If, after you produced the charcoal in this fashion, you ended up with 20 lbs of charcoal, it meant that the wood originally contained 25 lbs of carbon, total, so we vented 5 lbs into the atmosphere. Now the author of that site said it took an additional barrel of wood to start the reaction, so there's 12.5 lbs more carbon that we vented, so the total vented is 17.5 lbs of carbon as CO2, mostly, and we've sequestered 20 lbs, for a net subtraction of 2.5 lbs taken out of the atmosphere, or about as much carbon as is in half a gallon of gasoline. Not wonderful, however, think about this:

If you would leave that same 3 barrells of wood rot in a landfill over the next 20 years, it would have a net addition of all 3 barrells worth of carbon into the atmosphere, or a total of 37.5 lbs.

The difference then, between letting it rot, and sequestering it as charcoal is 40 lbs at immediate face value. Now, when sequestered, over these same 20 years, that charcoal is going to host living organisms, most of which are beneficial to soil. A lot of them die over time, and their microscopic corpses stay in the charcoal, adding to the carbon in the soil.
The weight of the carbon as micro-beasties living on and in the original charcoal over 20 years will increase to 60 - 80 lbs, plus the original 20 lbs of charcoal, for a grand total of up to 100lbs stored away for several thousand years.

Therefore now we have a net difference of 137.5 lbs of carbon from the simple act of preparing and incorporating 20 lbs of charcoal into your soil.
That is the equivalent of about 120 gallons of gasoline burned. So, in short, preparing 20 lbs of charcoal using this method, has the net result of not burning 120 gallons of gasoline over 20 years. If you could do this a couple times a year, you could, in effect, make your driving "carbon negative", meaning, you could take more carbon out of the atmosphere in this way, than you put in by driving your car. It would, however, take nearly 500 lbs of charcoal sequestered for every person in the USA to cover the use of coal in our power plants. I think that's probably way too unrealistic, as charcoal is very light, unfortunately.

This is the kind of grass-roots technology that could save us in the end. If we could somehow manage to get most of the wood waste out of the landfills, and into our gardens in this manner, we could go a long ways towards sequestering the current carbon dioxide polution, and buy us valuable time to find better energy sources.

And, if it improves soil fertility in the process, all the better.

There are already D.O.E. cash credits available for farmers who can "permanently" sequester carbon. I expect, as the US comes into line with the rest of the world on this, that these credits will expand somewhat, and what we are talking about here might actually become something of a profitable "winter occupation" for some farmers, providing they can get a free source of scrap wood.

Thanks Russell, for a heads-up on a good site, and for getting this tired old brain working on these numbers.

[Carm]

Wow amazing I never thought about it. I know that soap was made from lye which came from water run through ashes and was very castic untill mixed down or somthing like that. And I have been dumping my ashes on weed paches trying to kill them. But I haven't been here long enought Or thought I knew what I was doing and did not pay any real attenson to to that blind spot right in front of my nose. But I will be paying attension this next year.

Keep it up....all you need to do now is market the weeds as a cash crop and Voila! Just remember you got the idea from me!