Terra Preta

[potagere]

Thanks for the added explanation, Dan! I was about to ask Woodchuck : "What is hardware cloth!"

[Alan]

Mar 12, 2009 8:19:28 GMT -5 potagere said:

I've read a lot of this stuff, and a lot of it is unintelligible to me because my science knowledge is not so good, so I have a few questions to put to those of you who are better at this than I.
First of all, I need to point out that I have neither the skills, the technology nor the PLACE to start making my own low-temp charcoal.
That said, why could one NOT use briquettes?
Here in France (at least in my region), there actually are no briquettes to be had; barbecue charcoal is mad from real wood ("new" or "used") and seems to be produced with pretty basic technology. Why could I not try to use that?

An additional question, which is entirely peripheral: Alan, can you tell me more about your "wood burning stove with a thermostat damper" that you use in your greenhouse, or direct me to a source that will tell me more. I tried heating the greenhouse with an electric heater last winter, and that was a costly error, so this year it has remained cold. I was thinking maybe a pellet stove, but it sounds as if you have found the answer, so I would very much like to hear more!

Howdy Potagere,

Here is a link for the stove we use, it is the 1400.
www.usstove.com/products.php?cat=4

Two blowers and some ducting make heating the greenhouse fairly simple. I'll post some pictures soon.

[michaeljohnson]

No one answered my query- regarding if in areas where there are large forest fires every year like Australia and perhaps southern California, which leaves large amounts of natural charcoal on the surface of the soil together with wood ash, and it gradually incorprates itself into the soil, does this then not become a sort of Terra Preta layer of soil over a period of time.

[grungy]

Not really, Michael. The forest fires burn the detris and soil organism which would start forming the terra preta, just leaving a charcoal layer.

[grunt]

Michael: I answered you right below your question. I'll edit so it stands out a bit more.

[potagere]

Alan:
Thanks for the info & link for the stove. It gives me a good idea of what to look for in equivalents here. I'll look forward to the photos, because I get the impression that you are heating a much larger greenhouse than mine!

[mnjrutherford]

Greetings and Salutations! I was just given a referral to your forum by Pat from Bifurcated Carrots. My husband & I are small farming in coastal North Carolina. We have lived here for 3 years now but our land has been farmed for at least a hundred years prior to our showing up. The soil is essentially dead and we are working to change that. I recently learned about Terra Preta and I've been cogitating the notion.

As a christian of the sort that believes that God showed us how to live with the example of the Garden of Eden, I try to think of things as simply as possible. I also believe that when God gave us dominion over all the earth, "dominion" was not to be interpreted as "destroy". I ponder this when I cook as well.

So, when I read about the Terra Preta and it's contents and other chemical "statements" it makes, it is my opinion (guess, thought) that Terra Preta was the garbage dump. It was kept hot by dumping the still glowing embers from cleaning out home fires. At some point it may have been observed that it was a good thing to keep the pit at a slow burn because it would have reduced bad odors and probably kept unwanted insects at a minimum. When the pile got to deep, someone probably decided that it was getting out of hand and the best way to eliminate the problem was to spread the thing out in the garden area.

With this thought in mind, it is our plan to dig out a piece of turf slightly smaller than a piece of metal roofing (which is what we will use as a "lid") and 6 to 8 inches deep. We will then create concrete block, dry stack, walls on three sides. The "front" will remain be only one or 2 blocks high depending on how deep the pile gets. We will put ALL our garbage including animal feces and a few broken dishes. I'm not sure how we will keep it fired through the summer, but in winter it will receive the remains from the fireplace which will have hot embers.

At this point I'm thinking that it should be "built" over a one year period, then allowed to "rest" for 6 months to a year, then dumped into the garden. That means that 2 pits will actually be needed in order to keep the process cycling.

I have some problems with the notion of firing the thing with specially made charcoal because from what I have observed and read, the process is far more time and material intensive than would have been practical.

Thanks for creating this invaluable forum! I hope to read through the entire thing sooner rather than later and look forward the exchange of ideas and results to the various experiments.

[mnjrutherford]

One addition, I emphasized "ALL" garbage in my previous entry. I meant to distinguish that in our current compost pile we do not put meat or meat things or feces of any sort. It's just a standard compost pile. Garbage such as plastics and metals will not go into the pit. We recycle those materials in other ways as much as we possibly can.

[grungy]

Welcome to our "growing family". Glad you are here and please feel free to intoduce yourself and/or post anytime
If you are interested in tomato seeds, let us know. (wink, wink)
Cheers,
Val (grungy) and Dan (grunt)

[michaeljohnson]

Thanks Dan & Val, it becomes much clearer now- I missed the fine details a bit earlier.

[PatrickW]

Hi Jo, Welcome to the HG forum! It's nice to see you here.

To everyone else, Jo stopped by my blog a little while ago. I think she has lot of good ideas about sustainable agriculture to share with everyone here.

[mnjrutherford]

::blushing:: Thank you for the introduction Patrick! You are very kind! My extension agent will be grateful to have someone else listening to me sometimes!

Thanks for the tomato offers Dan and Val! I'm a big fan of tomatoes and my California gardens usually have upwards of 30 to 40 plants with 10 to 15 varieties. Here, after 4 garden seasons, I have had no (zip zilch nada) in the way of an edible tomato. I do believe the issue has been nailed to the wall this year. Don't suppose you have any virus resistant heirlooms?

I'm really looking forward to getting started on the experiment now that I know others are into the issue. I've sourced the "tin roof" and at least some of the cement blocks I'll be needing. Also, does anybody have any ideas or thoughts about why and how TP can filter air? I can't tell you where, but I have read that is one of the benefits of TP.

[mnjrutherford]

OK, here is one of my issues. Human feces. Found in the ancient pits, but pretty gross to ponder in this day and age. My issue is how do I get it into the pile. We have standard toilets and we have a septic system. Can we somehow get stuff from the tank to the pile? Could we flush and have it divert to the pit? If so, what about the water putting out the "flame". Composting toilet? Has anyone else cogitated this conundrum?

[canadamike]

The fact that it was found there does not mean they used it immediately. It might very well have been that they inoculated the charcoal with human feces and then later planted stuff on it, probably after some even distribution of the material.

[mnjrutherford]

I've finally looked through the whole thread. Fascinating.
1. Whole pots might be offerings to gods of some sort. Very plausible in my opinion. Another thought is that the pots may have been put into the trash pit because the contents spoiled. If so, the rotting food stuff would have permeated the pottery.

2. I'm not so certain the focus should be on the charcoal. We produce a good bit of biomass throughout each year. We also have a variety of terrain going from high and grassy down to a creekbed. I'll be posting photos in my blog for a different purpose soon, you are welcome to check it out. We also produce an astonishing amount of trash such as dog food bags, card board boxes (don't ask me how), paper goods (mainly napkins), food scraps, the 30 pounds of peanuts that went moldy because we didn't know how to dry cure them properly, and on and on.

3. Toilet stuff. Mike, you say "The fact that it was found there does not mean they used it immediately." I take it you mean that it was added last as opposed to being "cooked in"? If so, I'm not certain I concur. However, that is purely opinion and has zero scientific wisdom behind it. Just a female perspective that says "YUCKO! Not a chance I'm putting that on MY garden unless it's been completely sanitized, so if it isn't allowed to go through the dishwasher it has to go through fire!"

Urine, would urine burn or would it dampen the fire?

OK, now I need to bake some bread...