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Understanding Biochar

Biochar is being promoted aggressively as the miracle product for fixing soil, but does it work and if so, how does it work?   And as a carbon product, is it better than our TerraPro?  

This is my response to questions concerning Biochar.   There have been many products and many attempts to change the function of the geology of soil including adding substances to the site using products like compost, zeolite, adding a clay slurry to desert sand, Oxidized Lignite (also known as humate or leonardite), and Biochar.   

Adding anything to a soil, attempting to change its structure, its bulk density, its water management, or its nutrient value all use either a Mode of Action or a Mechanism of Action.    A Mode of Action is an anatomical change affecting living organisms, while a Mechanism of Action describes changes on a molecular level.   For example, putting compost into the soil provides nutrition to the soil biota, helping to support and possibly grow more biota, providing a Mode of Action.   Putting TerraPro onto a soil contributes subatomic particles and Functional Groups that provide a process of Quantum Physics that will change the arrangement of the soil particles and how those particles articulate with water and ions of nutrition, a Mechanism of Action.  

Let's take clay for example, where the company Desert Control  ( injecting a clay slurry into sand in an attempt to improve the sands ability to retain water.  The company calls it a "nano clay" but I'm not sure that's an accurate description of the size of a clay particle that would qualify it as a nanotechnology.  If the correct type of clay, it can help to attract and retain water in the soil, a Mechanism of Action caused by the CEC (Cation Exchange Capacity) of the clay, so if enough clay is added to change the bulk density of the sand, then the total CEC of the site can also be increased, therefore increasing the sites original texture to include clay, a Mode of Action benefit, plus the added benefit of increasing the electronegativity factor (the CEC) which is a Mechanism of Action.  So adding huge amounts of clay to a sandy soil can provide both a Mode and a Mechanism of Action.   For example, let's say that a site is dominated by sand and the CEC is 2, see the chart I've attached on the potential CEC of sand, silt, clay, compost, etc.,  and the CEC tells us how strong the negative charge is of the soil, or how much of anything with a positive charge it can grab and hold.  Remember, Cation minerals have a positive charge so the higher the CEC the more positively charged ions of nutrients the soil can grab and hold.  It works with water to, where one side of the water molecule has a positive charge, so the stronger the CEC of the soil the more water the soil can grab and hold.  This explains why sand can't hold onto much, while clay can grab and hold more!    By the way, Biochar is normally going to have a CEC value anywhere between 14 and 17 cmol/kg.   Back to the math needed.   Let's say we add clay to sand, so we have a mixture that is 50% sand with a CEC of 2 and 50% clay with a CEC of 25.  In other words, we put 1 foot of clay on top of 1 foot of sand and blend them together!   2 plus 25 divided by 2 gives us the average CEC of the blend which gives the new blended soil a CEC of 13.5.   One must ask, was this practical or economically feasible?  The question must then be addressed, does the amendment contribute an anatomical change by either providing food for the biota and vegetation or does it change the structure of the soil by using brute force capable of decreasing the bulk density of the farm soil, or does it contribute a substance that has powerful electronegative or electropositive forces because the molecules of the product are ionized and charged with Functional Groups, which provides molecular characteristics in the arena of Quantum Physics.   My associate, Dr. Kevin Divine who's copied on this email can probably correct me on my gross oversimplification of this science, but I'm trying to make this useful information by keeping it a bit simple.   

Now let's consider Biochar as a soil amendment and look at its characteristics and cost.  The question is, does it provide a Mode of Action or a Mechanism of Action or both, and if so, how?   I've used Biochar in the past as an additive to potting soil, where I found its low bulk density was suitable for making potting soil lighter in weight and less likely to collapse and become anaerobic (without oxygen).   Based on my experience with Biochar I'll take some liberties on describing it.  For example, if you measure its cubic foot bulk density it will weigh about 20 pounds.   Its CEC will run between 14 and 17,  lower than clay and much lower than compost, so based on that characteristic I can safely say its contribution will not be a Mechanism of Action, therefore it must be in its Mode of Action where it can help to lower the bulk density of heavy dispersed clay soil.  So let's do the math.   The Imperial or U.S. Customary measurement for the bulk density of the clay is 106.3 pounds per cubic foot.  Lets say that the PSI (pounds per square foot compaction) of a farm soil that's predominantly clay is at 300 psi and we know that microbes, oxygen, and roots don't like it above 150, so we want to lower it down by using a soil amendment that has a very low bulk density, in this case, Biochar.  Here's the math.  If the Biochar has a bulk density of 20 pounds and we add it to clay soil with a bulk density of 106 pounds by making a 50/50 blend of both, and mixing the Biochar into the native soil 1 foot deep, what do we get?    20 + 106 = 126 divided by 2 gives us the average of the new bulk density which is 63 pounds a drop of 50%.  If we assumed this drop in bulk density could be reflected in a drop in the psi by the same percentage then the psi of 300 would become 150, a value now suitable for microbes, roots, oxygen and water to penetrate.    Now lets look at the cost of Biochar to achieve this benefit.  

Placing 1 foot of Biochar on a acre of land would have this math.  1 cubic foot of 20 pounds X's 43,560 sq. ft. = 871,200 pounds of Biochar needed per acre to have a anatomical change in the soils bulk density to lower its psi from 300 to 150, or lower the sites heavy clay bulk density from 106 to 63 pounds.  According to Farm Energy the average price of Biochar in the United States is $1.29 per pound, making the cost to the farmer to buy this much Biochar a $1,123,848 dollars per acre.

In summary, the Mode of Action provided by Biochar may be effective at lowering the compaction of heavy soil or potting soil, but the cost of doing so would not be economically feasible     
The Mechanism of Action provided by Biochar is limited as the CEC is less than the average clay soil, and comparable to many farm soils with a texture of clay loam, so adding Biochar will not contribute an added benefit in terms of helping to attract, hold or store ions of nutrients, water or oxygen.  One of the claims about Biochar is that it provides a matrix of cavities where microbes can hide, however, this is a silly notion as microbes don't need to hide and in fact prefer to live in close proximity to the growing roots of plants that are leaking exudates of amino acids, fatty acids, and sugars, which the biota need to grow more biota.    

What's better than Biochar?  The Carbon Matrix of TerraPro, which provides both a Mode of Action and a Mechanism of Action benefit.    We've seen as little as 450 pounds per acre improve the moisture retention of farm soils in arid West Texas, 1000 pounds per mile of vineyard row decrease water irrigation demand by 400 % while increasing yield by over 55%.   At 2000 pounds per acre we've measured a drop in the psi of hard clay soils in pistachio orchards from 300 down to 75 going the full length of the penetrometer rod.   This change took place in one season. 

Feedback is encouraged.   Thank You

Michael Melendrez
CEO, Soil Secrets LLC
1850 E. Main St. Suite A2
Los Lunas, NM 87031
Office: 505 866-7645


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