BIOCHAR!
http://biochar.pbworks.com/w/page/9748043/FrontPage
I pulled out most of the useful information from this wonderful website. There is information on how to make it listed on the site that I didn't include.
"1.02 What are the benefits of using biochar in the garden?
The following benefits occur with additions of biochar
- Enhanced plant growth
- Suppressed methane emission
- Reduced nitrous oxide emission (estimate 50%) (see 5.10 below)
- Reduced fertilizer requirement (estimate 10%)
- Reduced leaching of nutrients
- Stored carbon in a long term stable sink
- Reduces soil acidity: raises soil pH (see 5.01 below)
- Reduces aluminum toxicity
- Increased soil aggregation due to increased fungal hyphae
- Improved soil water handling characteristics
- Increased soil levels of available Ca, Mg, P, and K
- Increased soil microbial respiration
- Increased soil microbial biomass
- Stimulated symbiotic nitrogen fixation in legumes
- Increased arbuscular mycorrhyzal fungi
- Increased cation exchange capacity
1.03 How much biochar do I need to apply to achieve these benefits?
This is the subject of ongoing studies. The degree of benefit clearly increases with the application rate. If you are satisfied with a very rough estimate, we would venture that a target application rate of 5 kg/m2 (1 lb/ft2) would be sufficient to achieve these results in most gardens. However, there are substantial benefits related to soil biology at rates well below 1 kg/m2. This FAQ includes information on how to use small amounts of biochar in your garden to best advantage. [peer review requested on target application rate statement]
1.04 How long does it take for these benefits to become apparent? How long do they persist?
Some effects, such as lowering soil acidity, occur immediately. Other effects depend on soil biology and take time to develop. Increased cation exchange capacity will take several years to develop fully. The good news is that these effects are very persistent.
1.07 Do charcoal properties vary with source and temperature? What properties are important to the gardener?
Charcoal's
chemical properties do vary with source and temperature. In the opinion of this author the single most important quality of charcoal to the gardener is the ability to lower acidity, also termed liming capacity or effective neutralizing power. This is easily measured in an agricultural laboratory as calcium carbonate equivalent (CCE). If you are growing acid-loving plants you will want a charcoal with negligible CCE, and purportedly this is true of Mulga (Acacia) wood, bamboo, and pine needle derived charcoal. If you are combating low soil pH and aluminum toxicity you will want a charcoal with substantial CCE. Oak and maple hardwood charcoal appear to have substantial CCE. Apparently Amazonian hardwood derived charcoal shares this characteristic. Raising soil pH has been identified as biochar's most important contribution to influencing soil quality in the context of Terra Preta. (
Source)
1.08 What temperature range is considered "low temperature" in the context of biochar?
The theoretical low end of the range approaches 120 deg C, the lowest temperature at which wood will char, (
Reference) thus the temperature at the pyrolysis front. A more practical low end is to use the piloted ignition temperature of wood, typically 350 deg C. (
Reference) The theoretical high end, between biochar and more traditional charcoal, depends on the process and feedstock used, but is seldom indicated in excess of 600 deg C. This temperature range is more relevant to woody charcoal than to charcoal made from bamboo, or other high cellulose fuels. Woody charcoal has an interior layer of bio-oil condensates that microbes consume and is equal to glucose in its effect on microbial growth (Christoph Steiner, Energy with Agricultural Carbon Utilization (EACU) Symposium, June, 2004) High temperature char loses this layer and consequently may not promote soil fertility as well. (
Source)
1.09 Can I substitute other forms of charcoal for biochar?
Absolutely. While the bio-oil condensates in biochar definitely play a role in soil fertility, charcoal without bio-oil condensates has been demonstrated to produce excellent results. It is normally advisable to avoid industrial charcoal briquettes because the binders used during manufacture can add undesirable constituents. On the other hand,
briquette binder can be innocuous. See below (5.0
for information on how to receive some standardized rice-hull charcoal to conduct your own home research pot trials, and compare your results with others.
1.10 Does charcoal break down in soil?
Charcoal is highly stable, however soil microbes do break it down, although at a very slow rate.
2.02 What can I grow to make my own charcoal?
In Britain commercially available charcoal is made from fuel produced by "coppicing" as has been done in British forests for more than 2,000 years. This is an ecologically sustainable use of forests and may contribute to the health and longevity of some British forests.
2.03 Can I burn to bones to make charcoal for my garden?
Yes. It appears that charcoal derived from bones, along with charcoal derived from other types of food wastes, was a component in Terra Preta de Indio. Bones are an excellent source of phosphorus, an element in limited supply in cellulosic charcoal. Initial impressions are that bone charcoal will have higher ash and CCE (See 1.07) than cellulose-derived charcoal.
3.05 Besides water, what else can I soak the biochar in?
You would want to choose materials that would mitigate stalling [ See 5.04]: Compost tea, MiracleGro™(
Calculation), fish emulsion,
urine,
more on urine, ....
3.06 Can I add biochar to compost?
Yes. This will help fill the biochar with biology and humic substances. For the added benefit of odor control, consider topping off each addition to the household kitchen scrap collector with a healthy layer ofbiochar.
3.07 Will biochar affect the compost process?
Casual observation indicates that adding fine, freshly made biochar may accelerate the composting process.
3.05 Will biochar harm the worms in my compost?
Composting worms have been
observed to be unaffected below 50% charcoal content, above which reduced worm activity could occur.
4.0 How do I apply Biochar?
4.01 What is the target application rate to achieve the effects of biochar?
From the data available to date, it appears that crops respond positively to biochar additions up to at least 50 Mg C ha-1, provided sufficient fertilizer is provided to prevent charcoal induced stalling (see 5.04). This is equivalent to 5 kg/m2 (1 lb/sf) and works out to a loose charcoal depth of about 5 cm or 2 in. (
Calculation) Crops may show growth reductions at higher applications. For most plant species and soil conditions studied to date, this growth reduction did not occur even with 140 Mg C ha-1."
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