North American Wood Vinegar

About Us


North American Wood Vinegar aims to create awareness about organic fertilizer, wood vinegar (Pyroligneous acid), and a global coalition connecting farmers with the resources they need to contribute to an ecologically sound food system and prosperous planet. The mission is carried out through the three pillars of the organization: information exchange, outreach and advocacy.
Wood Vinegar, also called Pyroligneous acid, Liquid Smoke or Mokusaku, is a dark liquid produced through the natural act of carbonization, which occurs when a biomass is heated in an airless container during charcoal/biochar production. The exhaust smoke from this charcoal production is condensed (cooled) into a liquid – this condensate then further separates into Tar, Vinegar and Bio-Oil.


Use of wood vinegar in agriculture dates back at least two millennia in ancient China, Egypt, Greece and India. Wood vinegar also has a long history and it has been used daily, for example, in Japan as a result of numerous health claims related to the product. Since the 1930’s, wood vinegar has also been used in agriculture as a fertilizer and growth promoting agent. Although the word ancient, related to  the use of wood vinegar, has been mentioned in many documents and on web pages it was difficult to find good scientific evidence to attest the first records of wood vinegar used as pesticide. Probably only few documents are available or the information has been written in languages and in countries difficult to reach via modern information retrieval

In conventional pyrolysis processes, wood is slowly heated up to the maximum temperature. Lower process temperatures (400 ºC) and longer vapour residence times favour the production of char. Besides slow pyrolysis, other terms such as carbonization, destructive distillation, and dry distillation are used for this kind of thermal process . The pyrolysis of wood was probably human’s first chemical process. It is known to have been practiced by the ancient Chinese. The Egyptians, Greeks, and Romans made charcoal by wood carbonization, and collected the condensable volatiles for embalming purposes and for filling joints in wooden ships.

The most important product of carbonization is charcoal. Industrial carbonization is carried out predominantly in large retorts with capacities up to 100 m3 of wood. The aver-age practical yields are about 35 wt% of wood, and depend on the wood species and wood size, carbonization system, processing time and final temperature. Beech wood is the dominant raw material for the production of charcoal in Europe. In addition, oak, ash, alder and maple are used. In North America, the raw materials include also hickory, elm, sycamore and some softwood species. In the Nordic countries minor amounts of birch is used, and in South America and South Africa, charcoal is produced mainly from hardwood species of Eucalyptus
Until the late 1800’s, wood carbonization was the major pyrolysis process, and supplied the increasing amounts of charcoal that were required for iron ore smelting. The iron furnaces in the USA used charcoal exclusively until the 1840’s, and somewhat later the share of the iron market produced with charcoal was increasingly replaced by that of coal and coke iron. By the 1900’s, destructive distillation of wood was practiced widely on a commercial scale by heating wood in closed retorts. The vapours produced were condensed to give tar (wood tar or sedimentation tar) and an aqueous layer (pyroligneous acid). In the retorts about the same quantity of the major products charcoal and raw pyroligneous liquor (crude wood vinegar) are produced. This liquor is first settled and then decanted from the sedimentation tar. The tar can be fractionated into tar oils and tar pitch. Raw pyroligneous acid contains primarily methanol, acetic acid and soluble tar. By the turn of the century, wood was the only source for the latter chemicals.