Terra Preta Recipes and Results

[Philip Small]

With all this talk of the need for measuring soil pH in the terra preta nova setting, I'd like to recommend my favored field approach: the Hellige-Truog Soil pH Test Kit. I have used these kits in my work for 3 decades. Accurate and inexpensive, the methodology allows you to focus on exactly the pinch of soil, or char, you are interested in. It was standard issue when I was a salaried NCSS soil mapper. The preferred NCSS field method is a now a pH meter for 1:1 (water:soil) but results from the HT kits are still acceptable.

Soil pH is so dynamic over short distances, and with this approach, you can sometimes get varied pH indicator colors in the sample, which I find particularly intriguing to view: for example all green hues, pH 5.8 to 6.4 and a point of bright yellow 4.0 from a root exudate. I wouldn't use it in lieu of a lab test, but I wouldn't hesitate to recommend it for dinking around and getting some quality face time with your soil.



Now if we only had an equivalent field kit for soil pE (aka redox potential), pH's energetic dance partner.

[Michaelangelica]

Originally Posted by Philip Small

With all this talk of the need for measuring soil pH in the terra preta nova setting, I'd like to recommend my favored field approach: the Hellige-Truog Soil pH Test Kit

.
The only kit available here is made by the CSIRO- highly respected. Should be OK

I would love a simple, quick electronic pH meter but either they are
1 Too expensive
or
2 too inaccurate
or
3 difficult to use- according to those that use them

Now if we only had an equivalent field kit for soil pE (aka redox potential), pH's energetic dance partner.

Could you please expand on this? I am no chemist or soil scientist

[Philip Small]

Originally Posted by Michaelangelica

.
The only kit available here is made by the CSIRO- highly respected. Should be OK

I'll see if i can find a source in OZ.

Could you please expand on this? I am no chemist or soil scientist

Just as pH is the negative log of the hydrion activity, pE is the negative log of the hydroxl ion electron activity. (source). Soil pE and soil pH are equally important to predicting charge state of metals and nutrients. However, because measuring pH is relatively easier by far, and because knowing pH tells us volumes about expected pE, soil pE is a less discussed subject. It is important to bioremediation, industrial chemistry, and wetland science. Not a household term.

These two are more than a mirror pair, although mirroring is their most notable characteristic. When pH changes, pE must also change in response. The reverse is true also. In soil, that response departs from simple mirroring. So much so that it can seem to be two separate dances.

Soil pH and pE have different causes of change and different effective buffering agents. The term 'buffering' is replaced in a pE context - it is called poise. A stabilized soil pE system is referred to as a well poised system, differences in soil buffering versus soil poise account for the departure from 1:1 mirroring.

Now for the exciting stuff. To many of us, what makes soil different than geologic material is that it is in an excited state, excited mostly by solar energy as facilitated by living processes. Unlike soil pH, soil pE is directly influenced by these energy fluxes.

The most influential cause of changes in soil pE is metabolic respiration aka oxidation. Oxidation doesn't necessarily involve oxygen. Oxidation does necessarily involve shedding an electron. Thus, living systems lower the pE of a soil system, and with pE in the dance lead, pH must follow.

Wetlands are low pE systems, wetlands with hydrogen sulphide odors are very low pE systems. Common agricultural crops, like wheat, cannot abide low pE systems. Rice is adapted to low pE conditions.

A well recognized soil buffering agent is lime, which buffers a soil to about pH 8.2. The major agent of soil poise is iron oxide, however soil manganese, although far less abundant, plays a more important, more dynamic role in most soil systems.

One soil scientist, Richmond Bartlett, was so taken with the importance of manganese in this regard that he opened his chapter on manganese in a 1995 soil chemistry text (1995, Environmental Soil Chemistry, edited by Don Sparks) with the phrase “We all should fall upon our knees and sing out praise for manganese”

Richmond Bartlett goes on to describe the role of manganese in terms that nearly describe a catalyst. Mn is not consumed, and the capacity for metabolic respiration increases in its presence.

This is sheer speculation on my part: from my view through the knothole, the nearly catalytic nature of traces of Mn is a finessing touch that makes char the wonderful soil reef it is. It is a fine point, and one hardly worth mentioning considering the much more important issues that need working out in our pursuit of Wim Sombroek's vision for terra preta nova.

[Philip Small]

Originally Posted by Philip Small

I'll see if i can find a source in OZ.

The Hellige-Truog Soil Reaction (pH) Tester kits are made by Orbeco in the USA however there is an Orbeco dealer in Australia: Extech Equipment. The kit is listed on the soil testers page as model 694. Extech's phone number is shown as (03) 9761 3300, and the toll free number for outside Melbourne is 1800 338 132. In the email reply from Extech, the sales manager mentioned additional shipping costs because the kit's reagent requires special handling in shipping. Hope this helps.

[Rev]

Well ill offer an alternative model for this biochar addition

im on about 30-40cm of loam to clay loam above clay on flat country
its inland in the subtropical area of northern NSW
subtropical in the summer, but quite cold in the winter. last winter the minimum was -6C but its usually 12-20 frosts a year at about -4C

the soil is already good but i want to make it better at holding the nutrients i put in

ive been making char is a few ways. making the char is as much about removing garden waste and dealing with problems involved like pathogens and weed seeds as its about the char

waste materials are food scraps, seasonal prunings, leaf fall, weeds, lawn clippings, spent mulch, card and newspaper, animal bones, and old bamboo stakes cut down at the local patch
waste is partitioned 3 ways; food grade waste goes to the chickens and ducks, low carbon : nitrogen ration waste goes to compost and high C:N waste now goes to char
the difference being around a C:N level of 25:1

char has been made 3 ways
1. managed open fire method. Some things char well and fast when openly burnt if the fire is managed. Grass, lawn clippings, straw.
a fire is lit and materials thrown on a little at a time, the next addition smothers the previous stalling it in a char phase before it burns to ash , or else i wet it down or tamp it out. it can be fairly quick and productive

2. In a steel bin. a convereted 60L oil drum with holes in the base and a lid if needed. paper products, leaves, bamboo wastes, sticks especially thorny ones liek rose prunings and infected plant materials
same strategy as the open method, keep filling it. soon it gets very hot and material chars without completely burning and flames shoot out the top some distance.
good to get rid of paper especially and the whole thing is quenched with the hose when im done

3 earth mounds. this is good for the big stuff. light a fire get it roaring then load on more wood and what youve got - then cover the hole thing with dry woodchips then with earth so just a tiny amount of smoke seeps out. if smoke increae mpatch up with more earth. a slow but easy process
when finished break apart and the yield scan be quite good.

my favourite method is to take the char from any method and run through a garden sieve. large chunks go around the fruit trees , fines fall through and go to a gedye style compost bin.
in this i build up alteranating layers of char , household and garden scraps of low C:N ratio and some additives - like rock phosphate, Bone meal gyspum or dolomite to add the crucial P, Ca and Mg that are so characteristic of the black earths. Once full i let it sit till i need it t o dig into a new bed

if using plain char i like to mix it 50:50 with compost (not a rich one so i add a complete NPK fertiliser and some powdered Kelp)

The results are very promising
fungi and worms visibly love the half burnt materials
and growth rates have been sustained

i would like to see char levels hit 35% in the top 20cm in time
but id also like to see compost additions equal annual char additions
and it must remain finely textured - for vegetables
and i continue to fill up that space with the ions of Mg, P, Ca, ammonium and sulphur

all waste (large) char goes around fruit trees.

ive used 50:50 char:compost as a potting soil for vegetable seedlings with excellent results - and cheap!

i dont apply char to acid lovers.

[Ahmabeliever]

10 % charcoal
90 % compost

For each 10 Gallons of the above

Handful of blood and bone
Handful of dolomite lime
2 handfuls yellow clay crushed to dust and sprinkled in (all I had then)

Watered with rainwater brewed with bacterial and fungal innoculants.

Placed in holes dug into surrounding clay soil (wound up 50/50 clay and 50/50 my mix).

The soil won't yield crops with similar (composting) methods in past. Nothing but ugly gardens that refused to flower or flowered way too early and died. Adding compost turned the clay to brick, if not immediately, after a few rains and walkthroughs.

Results are brilliant now. Better water holding capacity, mold resistance, porosity, lightness and tilth. Rapid growth of vegetative greens, fruit set occuring normally albeit heavily in tomatoes.

This is a successful experiment in correcting a soil previously capable only of growing weeds and grasses.

I will amend a larger area shortly, upon being able to make my own charcoal. Am storing bones and old pottery for the next run.

[Moontanman]

Originally Posted by RBlack

To All,

I thought we might need a thread on how we use Terra Preta and results.

I took the liberty to put on a couple from other sources.

Mine: I have solid clay - no SOM soil that I am amending. I have made charcoal from pine and biochar from kitchen wastes, pine needles (to lower soil ph- wild idea of mine), and mule manure. About 50% charcoal, 10% kitchen wastes, and 20% both pine needles and manure. I am composting it with regular compost material; kitchen scraps, dead leaves, grass clippings and a fair amount of Bone Meal, about 5 times recommendation for my size of garden (this replaces the fish “residue”, bones, and turtle shells that the Amazonians had in their mix). I don’t have the time to compost this correctly because I got a late start but it will have about 6 weeks before I till it into the clay on April 9 – 11. I will let this sit in the soil until I plant on May 12. This is a VERY experimental mix for my particular soil. I will plant shade tolerate garden crops of which I am still trying to figure out what. Right now absolutely nothing grows there and hasn’t for two years. After all the snow melted it has grown a green slime across the top but I don’t consider this a “crop”. I am very interested to see what weeds I get between April and May as this will show if I have a fertile soil or not.

This was from Make do:
We're using a typical 55 gal drum charcoal maker to produce so far hardwood and softwood charcoal, and plan to try these other sources over 2007; One or more sources may prove to provide biochar suited to northern new England. To date we've been growing wheat and chia as test species, in trays of 75% vermiculite, 25% hardwood charcoal, The controls with no charcoal; both with rainwater and sea solids. Wheat roots grew approximately 50% faster in the biochar-mixed ones than the control ones, The Brix (refractive index, or nutrient density) was about 40% higher in the stems of the charcoaled wheat, but around 50% lower in the roots than the control wheat. Interesting potential for wheat-farming.

This was from Janice Thies posted on the original thread:
Lastly, from my personal gardening experiences, I use spent charcoal from the filters of the 14 aquaria I maintain for my viewing pleasure. I combine it as about 5% of my mix with 65% peat moss, 10% vermicompost (from my worm bin in my basement where I compost all my household kitchen waste - aged and stabilized, not fresh!), 5-10% leaf mulch (composted on my leafy property in NY), 5-7% perlite to increase drainage, decrease bulk density and improve water retention and percolation, and some bone meal and blood meal (to taste :-) ). This makes an excellent potting mix for my indoor 'forest'. I am very much still playing around with this.

Thought I would start with these 3 although I know there were many more from the original thread.

RB

I make an aquarium soil that is similar to what you do at least from the charcoal point of veiw.

Azzola Compost

Ground charcoal

Earth Worm Castings

Peat Compost

Oak Tree Leaves (ground)

Oak Tree Leaves (whole)

Lava Rock Flour

Phosphate Rock Flour

[Ahmabeliever]

That's a fascinating mix from an Aquaponic point of view Moontanman.

I've played with peat and phosphate for increasing Adenosine Tri Phosphate production but haven't the facilities to document if it 'really' works at all. Can tell you what I did if you like.

This was to increase CO2 production in the water as well as boost plant growth in the attached beds. Plants certainly took off in the beds, was too cold for the lillies then.

Sure I could repeat it but not too sure how it affects the fish.

I'd love to hear more about your mix and how you came to select it, it sounds very good.

[Moontanman]

Originally Posted by Ahmabeliever

That's a fascinating mix from an Aquaponic point of view Moontanman.

I've played with peat and phosphate for increasing Adenosine Tri Phosphate production but haven't the facilities to document if it 'really' works at all. Can tell you what I did if you like.

This was to increase CO2 production in the water as well as boost plant growth in the attached beds. Plants certainly took off in the beds, was too cold for the lillies then.

Sure I could repeat it but not too sure how it affects the fish.

I'd love to hear more about your mix and how you came to select it, it sounds very good.

I started making my own soil when I grew cacti, at the time I only used sygar sized sand for my aquariums but so many aquarium plants are such heavy feeders I decided to mkae a soil for aquariums, /commercial soil contains way to many aditives ti really be acceptable so I used what i had on have that was already found in swamp soil, excpt maybe the charcoal.

[Moontanman]

I'll probably leave out the phosphate next time, too much blue green algae growth from it.

Michael