Hi All, I just found this article. I am a fan of biochar and it's potential. I hope for the day of mobile biochar makers, going from farm to farm along with the combines, processing crop waste for redistribution on the fields. The fact that char keeps nutrients in place and allows for greatly decreased levels of fertilizers to be used sounds like a great step for large producers and better overall for watersheds. Ideally we wouldn't have all these large producers, but perhaps, in the meantime...
Rice hull char has been used in Japan since the 1600's.
I had never heard of wood vinegar. It sounds like something to check out. Maybe it could be applied at the same time as biochar to alkaline soil to ameliorate the initial ph imbalance potential?
A quote about wood vinegar -
The concentrated liquid of wood vinegar with strong acidity can kill microorganisms, plants and some larvae, but the diluted form stimulates rooting, plant growth and microbial propagation. There are many reports of the application in field practice and generally the effects have been well known by users, but there are a few available scientific reports on the mechanisms associated with the chemical properties.
The oldest description on charcoal use in agriculture is found in a text book, “Nogyo Zensho (Encyclopedia of Agriculture)” written by Yasusada Miyazaki in 1697 (7). He described in it; “After roasting every wastes, the dense excretions should be mixed with it and stocked for a while. This manure is efficient for the yields of any crops. It is called the ash manure”. Probably similar knowledge had been popular in China and Korea since ancient time.
In Asian countries, rice husk charcoal which can be carbonized by simple methods in field soon after harvesting has been one of the most common materials for soil amendment. It seems that rice husk charcoal has been used for several thousand years since the beginning of rice cultivation in Asia, because rice husk with high content of silica is decomposed a little in soil and useless as a compost material.
The custom using rice husk charcoal mixed with excreta had been very popular among farmers particularly in wheat cultivation until about 60 years ago. There seemed to be reasonable benefits, because the charcoal can absorb and keep chemical nutrients and deodorize the excreta. However, this method was too popular to investigate for scientists. This led to the roles of charcoal in agriculture being neglected for long time. After the information on wood charcoal use was circulated in1980’s, the roles of rice husk charcoal were recognized and investigated by agricultural researcher again.
For instance, recently Ezawa et al. ( reported that rice husk and its charcoal enhanced A (arbuscular) mycorhiza formation of some crop plants and improved soil physical properties when each material was added top soil. Ishii et al. (9) also reported the same effects on the A mycorrhiza formation of citrus seedlings. Komaki et al. (10) suggested that a small amount of rice husk charcoal could increase the growth of Catharanthus roseus, but the browning of leaves appeared with the excessive application because of high concentration of potassium and higher pH of rice husk charcoal than wood charcoal. Takagi et al. (11) proposed a practical method to reduce the outflow of pesticides and herbicides from paddy field utilizing the absorbing ability of rice husk charcoal. Also he tried to fix the bacteria with high decomposing ability of pesticide into rice husk charcoal and succeeded to reduce the outflow of herbicide simazine from a golf course (12).
At present, carbonizing methods have developed from the traditional kiln to the sophisticated facilities equipped at rice mill. Dried rice husk can be carbonized automatically and continuously in a self-fuel kiln and the extra heat is utilized for small scale power generation (13). Recently the facility and system has been exported to South East Asia by Kansai Sangyo Co. Ltd. It is probably possible to apply this automatic carbonization technology to wheat and barley chaff and other crop plant residues.
I know there is a forum member here that uses rice husk charcoal. I hope all this isn't just a repeat of previously posted - apologies if so...