Interesting Soil Ammendment, Charcoal
 

I've been reading about terra preta lately and while it looks like it takes 50 to 100 years for that system to really ramp up one of its prime components, charcoal, can be used immediately. The charcoal helps to add loft to the soil but it also absorbs nutrients and minerals like a spong, and holds them against rain and other cycles that would naturally and slowly wash away nutrients. Plant roots on the other hand have a mechanism by which to extract these nutrients. The charcoal will enhance the soil's ability to hold air and water, too. In addition to standard compost it seems worthwhile to add a certain ammount of charcoal. Because large branches and other woody wastes take a long time to break down in a standard compost pile rendering them into charcoal and potash would allow such materials to enter into the soil very quickly.

Re: Interesting Soil Ammendment, Charcoal
 

This seems fairly obvious now but I had been thinking about digging test beds when I read about somebody else using charcoal-ammended native soil in pots for testing. I will pursue this method with a variety of things I've been trying to grow. One pot will be ammended, the other not.

Re: Interesting Soil Ammendment, Charcoal
 

read somewhere that to much carbon (charcoal,sawdust etc)at one time can deplete the soil of nitrogen cant remember the exact reason think it had something to do with earthworms having time to do their work.

Re: Interesting Soil Ammendment, Charcoal
 

I've also read recently that the primary contribution of compost is carbon. I know compost piles burn nitrogen. Still researching this.

Here's some interesting info on terra preta.

link: http://www.bidstrup.com/carbon.htm

Re: Interesting Soil Ammendment, Charcoal
 

Charcoal sounds touchy. I know that burning causes unfamiliar effects--ie moonflower takes over as it is immune to burning. Firepits show the same thing, with burned stumps being virtually impervious to decay even in conditions of 50 years.

I'm feeling that it's like those vermiculite bits in potting soil--good to a point and bad thereafter.

Might look into lasagne composting as a good way of testing/metering your charcoal dose:

http://www.homestead.com/TBMasterGar...Gardening.html
(no wiki on this but there are books)

This is just as doable in situ, because lugging compost is unnecessary work if there's any way to do it in place.

Remember if you're making charcoal, there are ways to use the energy/heat from the gasification, either in a conventional IC engine, or just to heat the ol' homestead (garage?)with smoke pipes. To me, charcoal is too valuable as energy to use as compost. Better to lay the raw material, wood chips, leaves, etc and let nature do the work of oxydizing it.

TS

Re: Interesting Soil Ammendment, Charcoal
 

Lots of info in the thread at the following link.

http://forums.hypography.com/terra-p...arted-all.html

From what I've been reading it sounds like the Amazonians responsible for terra preta were burying their dead in their fields, probably composting and humanuring on a large scale, too. Makes sense, that would return nearly all the extracted minerals back to the soil from which they came.

As far as making the charcoal goes, since it has to be fine grained anyway you can make it from things that wouldn't yield charcoal that would be particularly interesting as fuel, like crop residues. I agree that trying to utilize the heat and gasses make sense. I am interested in the iron pipe and parabolic trench solar method of production, I've got a number of iron pipes that were left on my property by the previous owner so I just have to come up with the parabolic trench. This method would be much faster than letting a compost pile carbonize the biomass over a period of months or years.

I have good loam in the back half of my property but heavy clay in the front half. The more I learn about it the more charcoal and terra preta sound like a great way to improve my land, my soil and climate is not far removed from the Amazonian conditions and I have plenty of biomass available. I might try to make a small sample batch today.

Re: Interesting Soil Ammendment, Charcoal
 

No doubt it's better in FL, the jungle has terrible and unique problems with soil depletion and I imagine that the rate at which nutrients are used, year-round, is over-high as well. This is what happened when we used to rototill regularly. Great crops, but rapid depletion difficult to reverse.

Temperate climes probably have access to much more leaves, trash, etc that can be broken over the year, since they're all down for the winter and have frost heave and other seasonal decays. I can't imagine it since I already see that year-round depletion problem by VA/NC.

Are there crops for your climate that can do the same thing? The ones I've heard of are all for overwinter, or digging deep clay like radish and clovers.

I wonder if charcoal is just "seed" for the microbes to colonize in. If so, that idea seems workable.

TS

Re: Interesting Soil Ammendment, Charcoal
 

Micro-life is no doubt a good part of the equation as is the charcoal acting as a resovoir for nutrients but I wouldn't discount the value of simply breaking up the clay. Fine soils are sticky, but fine charcoal is a more like a lubricant if anything. The most fertile terra preta soils are said to be between 9% and 40% charcoal and I've gotten either very poor germination or stunted plants in my experiments when sowing in the native heavy clay soil on my property. I have some clay dug, now I just need to make some charcoal.

Re: Interesting Soil Ammendment, Charcoal
 

All right, I made a half gallon of finely ground charcoal today and ran some tests on my heavy clay from the front of my property. Here are the results.

100% Clay Soil: Imagine modeling clay with rocks in it and you'd about have it.

50% Straw: Worthless! and that's all I have to say about that.

25% Coarse Sand: The soil became more gritty but that was about it.

50% Coarse Sand: ...did manage to make the clay friable and somewhat improve the water holding capacity. It also made the soil look more washed out and it felt like a weird sandpaper putty when worked with the hands. Not pleasant stuff but you could probably grow something in it.

20% Charcoal: The soil started becoming fiable and water holding ability was dramatically increased. Starting to look and feel like real loam.

50% Charcoal: Looks and feels like real loam, friable when wet and increasingly so as it dries. Radically improved water holding capacity.

It required less charcoal to reach the desired effect and it was easier to mix in than the sand was. I see real potential in terra preta, or terra preta nova as modern attempts at recreating the pre-Colombian original are sometimes being called. I plan to use this ammendment in conjunction with double digging for my market garden. If one needs a lot of charcoal I could see trenching the area you intend for the garden beds, piling in the wood and such for the charcoal, starting your fire and then mounding some dirt over after it's well on its way as per the usual charcoal making technique. After the charcoal is done attack the bed with the till tool of your choice and begin adding in the remainder of the soil you removed from the trench as the charcoal is broken down and mixed in.

If you're interested in more closely approximating real terra preta rather than just using charcoal to break up your clay you'll have to add other things into the mix, too. I believe the pottery is incidental, a side effect of other processes. What you will definately need is compost, bone meal and a source of nitrogen like fish emmulsion or whatever. If you'd like to innoculate your soil with beneficial microrganisms you would probably get a good jumpstart on the process.

Re: Interesting Soil Ammendment, Charcoal
 

This may or may not be pertinent.

I remember in down town St. Louis there were Ash pits for homes that burned coal.

My mother had a Friend that bought one of these homes and the prior owner raised chickens. The prior owner threw dead chickens in the ash pit and it was left or covered.

When My mothers friend bought the home she planted tomatoes in the ash pit soil-dirt and you could not imagine the superior quality. Huge-easily 2xs as big and deeeeeep red.

Anyway I know you have chickens and ashes so I thought I'd mention.

Ashes-coal, Bones, etc make for some excellent tomatoes.

Electric-Amish

Re: Interesting Soil Ammendment, Charcoal
 

During the War--WWII meat was rationed.

My Dad and his family raised rabbits and chickens in their basement. My fathers job was to clean out the poop daily.

He would dig a trench along the garden and empty it into the trench then bury it. At the end of the row he would dig a trench going parallel again and do it again.

This was how he told me he kept fertilizing the garden. they would leave an area maybe three rows open during the growing season for the manure disposal. Then move along until they covered the whole garden.

E-A

Re: Interesting Soil Ammendment, Charcoal
 

While double digging a 5x20' bed I encountered some heavy clay about six inches below the surface. As I was just starting the project the dirt from the first trench, about 1x5', was placed in and just filled up a 40 gallon basin. Remembering last night's soil samples and having a useful volumeteric measurement I was able to determine that it would take 8 gallons of charcoal to treat 5 square feet of garden bed to 20%, or 160 gallons of charcoal to treat the full 5x20' double dug bed. After a brief survey I found that I had enough fallen limbs on my property to produce the required 160 gallons of charcoal so I am going to be making a 5x20 terra preta test bed over the next month or so. I should have it done in time to plant a number of Fall and Winter crops.

If the tests go well I have enough dead trees on my property to manufacture the 4,000 gallons of charcoal required to treat the 2,500sqft of beds in the market garden I'm going to start this Fall.

It looks like there are four nutrients the charcoal is particularly good at holding in the soil... nitrogen, phosphorus, potasium and calcium.

Re: Interesting Soil Ammendment, Charcoal
 

Nitrogen = Base components of protein = tissue

Carbon = Energy (as in carbo-hydrates)

Minerals = Structural Building Blocks / Electrical conductors


Soil microbes need to eat a balance of protein (nitrogen) and energy (carbon) along with a supply of minerals in order to thrive, reproduce, and grow. With too much energy (carbon) available, microbes attempt to grow and reproduce as fast as possible but are protein starved, grabbing every bit of available nitrogen. With too much nitrogen and not enough carbon (energy), too few good microbes sluggishly swim in a cesspool of nitrogen waste (which is why nitrogenous material, lacking enough carbon, smells bad).

Take some damp nitrogenous material (urine, feces, dead animals, green grass) and put it in a pile in a warm area. Come back in a couple of days and smell it. Yuck! the few good microbes are swimming in a sea of nitrogen/protein and have no energy to eat this pile of ooze. Now add a bunch of carbon, and the good microbes will have the energy they need to reproduce quickly and eat the mess. With the right balance of carbon and nitrogen, there will be no smell. This is why straw (carbon) has been used in barns for eons. Animal feces and urine won't smell if you add enough carbon to allow microbes to have a balanced diet. Understanding the carbon and nitrogen cycles is critical to sustainability. Understanding how microbes make the soil, that plants thrive in, is critical to gardening.

By the way, we will never have true sustainability (a continuous loop) on a piece of land unless we cycle everything including our own urine and feces and even our own dead bodies. If we don't cycle everything, then we are simply mining the existing nutrients from the soils in a one-way process and sending those nutrients away to the garbage dump and sewage treatment plants.

Reality

Re: Interesting Soil Ammendment, Charcoal
 

As far as carbon cycles go it is important to note that the finely ground charcoal in terra preta is very stable, unlike carbon in dry grass clippings or similar. Some Amazonian terra preta deposits contain charcoal that is many hundreds or even thousands of years old. While some carbon probably is broken down and utilized by microrganisms it seems the main effect besides improving soil texture is in water and mineral retention and providing superior habitat for the microrganisms to live on. Apparently the structure of the charcoal is such that it offers a huge ammount of surface area compared to other soil particles.

It does indeed appear that the pre-Colombian civilization that initially invented terra preta did in fact return their garbage, waste and dead to the soil. Very sensible, actually. While I don't think I'm ready for humanure or burying dead guys in my yard I will be returning other organic wastes, animal manure, bones, etc. I'm looking to my half acre pond to make up the difference as I can harvest it for fish emulsion and compostable aquatic plants like duckweed. There are other sources that come in from off site as well, like bird and animal droppings, insects and the terra preta soil will capture the disolved nitrgen from rains.

Looks like I'll be digging the pit for making charcoal tonight and gathering up as much wood as I think I'll need. I'm going to make the pit a little bigger than the required volume so when it fills up I should have about enough.

For the big market garden I'm estimating I ought to be able to get near 100 gallons of charcoal per charge out of a dual 55 gallon drum retort setup which should be more efficient than the pit. It'll probably end up being a little over 40 charges to make enough for the 2500sqft of bed I have in mind. That's a lot of smoke but I'll be doing it over 6 or 7 months. The neighbors enjoy a good fire as much as I do anyway. :wink:

Re: Interesting Soil Ammendment, Charcoal
 

I got the pit dug today, a bit over 200 gallons in capacity. This time of year there are only a few workable hours during the day with temperatures only a couple degrees off 100F and 80% humidity. Then the mosquitos come out when the sun starts going down. Things slow down.

Anyway, I'll be gathering the wood tomorrow and should be able to do the burn. Still on target for finishing the bed by the end of the month, I'll be able to test it on carrots, brassicas and a few others.

I also did some calculations and found I will need to grow about 6,000 sunflower plants to produce enough seed to cover all my chickenfeed needs. Taking into consideration that I can grow an oil sunflower every six inches in a doubledug bed, that I can get in 3 good crops per year and terra preta is perfect for sunflowers it should only take 1500sqft of garden beds for this crop which will also yield fuel and cooking oil.

Re: Interesting Soil Ammendment, Charcoal
 

The charcoal pile took several days to finish burning and consumed a lot more wood than I would have prefered. I think part of the problem was my instinct to build a fire rather than charcoal took over while piling up the wood. Part it is just process inefficiency plain and simple, though. Given the loss rate and time it takes to finish the burn I'm moving with the retort method.

I found a place not too far away that sells reconditioned 55 gallon drums, $20 for the plain type and $25 for the kind that has a threaded hole near the bottom that accepts standard 2" steel pipe. That's for the lids, cleaning, repaint, lining inside if you want it, everything. The value of this product is mindboggling. I can hardly imagine anything as useful as a 55 gallon drum being that cheap. I'm going to be buying more for other projects like a savonious turbine, rain barrel, worm farm, storing feed and grain, settling the vegetable oil I'm growing... actually I'm scouring the web right now for other 55 gallon drum projects, these things are too great of a resource to go to waste!

The double digging has commenced. I'm mixing in duckweed for compost and will add the charcoal as a top dressing to dig in when I'm done. As always the hoe is speeding up the process considerably.

Re: Interesting Soil Ammendment, Charcoal
 

Remember reading an article on Mayan agriculture. They dug ditches then havested and burned the water plants that grew in the ditches on the berms. That's where they grew their crops.[bet they ate the fish in the ditches too]

Thanks for the info Rev! It is giving me some ideas.

Re: Interesting Soil Ammendment, Charcoal
 

REV. thanks for another informative thread...when it comes to one of your projects you're like a Pitbull that just won't let go until the job is done to your satisfaction.

Re: Interesting Soil Ammendment, Charcoal
 

I didn't read every post but if you are trying to make a heavily clay soil drain like a sandy loam I think that you can pretty much forget about it. A little clay is good, a lot of clay is bad. Raised planters or a green house might be a better way to go.

Re: Interesting Soil Ammendment, Charcoal
 

You can't drain anything unless you have some place for the water to go. Generally speaking French drains, dry wells and ponds are your best bets for drainage. If you can dig far enough to get below the clay layer you have a chance too, but you'd have to be lucky enough to have only a relatively thin layer of clay over sand.

I'm ammending the clay not primarily for drainage but to make it farmable. Root systems can get stunted in heavy clay and from there the rest of the plant suffers. The charcoal in terra preta breaks up the clay. The other problem is water runs off clay fairly easily, once again the charcoal comes to the rescue by enhancing the water holding ability to a noticeably greater degree than adding sand would.

In my case I'm digging a 600 cubic foot dry well or garden pond for primary drainage. The removed clay will be used to construct a cob chicken coop, large capacity zeer pot and compost bins. The double dug beds will loft out to just about a foot higher than ground level after compost and a 20% charcoal ammendment. Over the following year or two I'll be trying to get to around 40% charcoal and continue adding compost so that will add a few inches as well, enough to protect from flooding even without drainage but that of course won't keep your feet dry.

Re: Interesting Soil Ammendment, Charcoal
 

Rev, I encourage you to look into base saturation theory. Part of this agronomic theory holds that the chemical compostion of soil affects the physical condition of the soil. That is, the balance of the minerals will affect how tight or loose a soil is. Typically, when a soil is high in magnesium, and/or low in calcium, the soil will be "tight," and non-porous. When certain balance of these two minerals is achieved, based on the soils cation exchange capacity, or CEC, the soil will become more friable.

http://kinseyag.com/

http://www.soilandhealth.org/01aglib...pH.bal.nut.htm

Base saturation theory was pioneered by William Albrecht. What he did was take thousands of soil samples from excellent producing areas, to poor producing areas. What he discovered was that the better a soil was, the closer its mineral content fell into a certain balance.

Right after WWI he took a soil map of the US, and overlaid a map of draft data. Back when people ate much more locally, he was able to show a strong correlation between general health and the soil. Where there was good soil, there were more healthy men that got drafted. Where soils were poor, there were more men that failed physicals.

Albrecht was the head of the soils department in Missouri for decades, so was no crank. Why his findings have never been more widely disseminated, I'll never know.

Re: Interesting Soil Ammendment, Charcoal
 

I will take that under advice. I haven't gotten a scientific soil analysis done yet. I do know phosphorus is mined in my area and we have a lot of limestone.

I was just looking at the backyard aquaponics site and noitced they were using gravel as a substrate in their grow beds. I worked on a hydroponic operation that used pearlite long ago. It seems to me that chunk charcoal would be better than either and basically free for me. I might try this out.

Re: Interesting Soil Ammendment, Charcoal
 

I reccomend Kinsey's soil lab. It is very expensive, $50 a whack, but it is probably the best. Further, if you wish to try base saturation, I think his soil test is mandatory, as the percentages of bases in the soils are based on very specific soil tests.

Re: Interesting Soil Ammendment, Charcoal
 

My ranch in Virginia is partially no perk clay, and on the area's where we have burned brush piles, the grass and clover is much greener and much more lush.

Re: Interesting Soil Ammendment, Charcoal
 

Funny you should mention that. In my state brush fires are a natural part of the renewal cycle. While it burns away old growth to make room for new it also creates a certain ammount of potash and charcoal. I was thinking about this the other day while walking through some recently burned woods.

I've been seeing a lot of felled trees and wood going to waste lately while driving around. I keep wishing I had a way to get it all back home into the charcoal retort.

Speaking of which, if you're messing with a 55 gallon drum you're going to want the right wrench. You might be able to get one from the people who sell you the drum or you can find them online for under $20 shipped. They're usually made of aluminum for the non-sparking qualities. I had to buy some pipe at Ace Hardware so I got to ask the associate if he had a wrench that would fit my two inch bunghole. It was a guy a couple years younger than me, tried real hard to keep a straight face. He asked what it looked like, I told him it had four prongs to fit the bung and was about a foot long. Man, it was a bad scene! Yeah, better order your bunch wrench online.

As far as drilling the holes in the iron pipe goes I thought I'd need a carbide or cobalt drill bit. Ends up a standard wood/metal high speed steel bit drilled the 14 holes just fine, but showed signs of needing to be sharpened towards the end.

I've been rained out of working today so I might be falling a bit behind schedule but about 25% of the bed is dug so far.

Re: Interesting Soil Ammendment, Charcoal
 

Just an update for anybody who was interested...

I finished the test bed, ended up making 125sqft. It is currently growing lettuce, mustard, cabage, broccoli, tomato, carrot and sugar beet. I also have hot peppers going in pots. So far so good!

I have read that the charcoal will initially absorb a large ammount of available nitrogen from the soil so if you go this route you'll want to add nitrogen after the charcoal. Fish emulsion is one possibility for the future, right now I'm just dousing it down heavily with pond water. The charcoal is said to also make the soil more alkaline. I primarily used pine for the charcoal because pine is acid. I've tested the ph and noticed no measurable change compared to the unammended soil.

Re: Interesting Soil Ammendment, Charcoal
 

I am not sure of the science behind this but the C to N ratio is very important to composting. The guy that buys class A biosolids from my tretament plant is very keen on this and part of the production agreement is to produce a compostable material. We verify this by doing a C/N ration test. TO much carbon and the process is smothered, not enough carbon and the process fizzels out for lack of feedstock.

Pretty noinformative I know but it was the best I could offer.