Wood Vinegar
Cooperating agency for this topic:
Agricultural Chemistry Group,
Agricultural Production Sciences Research and Development Office
Department of Agriculture, Thailand
Paholyothin Road, Chatuchak, Bangkok 10900, Thailand
Tel. 66-2579-3579 Fax. 66-2940-5736
E-mail: panpimon@doa.go.th, 2005-12-01
Wood vinegar is a byproduct from charcoal production. It is a liquid generated from the gas and combustion of
fresh wood burning in airless condition. When the gas is cooled, it condenses into liquid. Raw wood vinegar has more than
200 chemicals, such as acetic acid, formaldehyde, ethyl-valerate, methanol, tar, etc. Wood vinegar improves soil
quality, eliminates pests and controls plant growth, but is slightly toxic to fish and very toxic to plants if too much is applied.
It accelerates the growth of roots, stems, tubers, leaves, flowers, and fruit. In certain cases, it may hold back plant growth
if the wood vinegar is applied at different volumes. A study shows that after applying wood vinegar in an orchard, fruit
trees produce increased amounts of fruit. Wood vinegar is safe to living matters in the food chain, especially, insects that
help pollinate plants.
Wood vinegar is made from burning fresh wood in a charcoal kiln, made from a 200-liter oil drum and
120-cm-tall concrete chimney with a 4-inch diameter. The kiln contains 63-83 kg of fresh wood. Wood good for vinegar must
have a heartwood.
Process
- 1. Cure wood that has heartwood and bark for 5-15 days.
- 2. Pile wood in the kiln (Fig. 1). Close the kiln and cover every hole with clay. Burn it at 120-430oC.
- 3. After 1 hour, put a tile at the top of the chimney (Fig. 2). If brown or dark brown drops appear
on the tile, allow smoke to flow through a bamboo pipe so that the hot steam may be condensed into
liquid.
- 4. Place a vessel to collect the vinegar drops from the bamboo pipe.
- 5. If wood is burned for 12-15 hours in a 200-liter oil drum kiln, it should produce 2-7 liters of
wood vinegar. At this stage, it is called raw wood vinegar.
- 6. Leave the raw wood vinegar for 3 months to become silted. The vinegar will turn yellow like
vegetable oil. After which, it will turn light brown and the tar will become silted. The top content will be
a light, clear oil. Remove the tar and light oil, as well as the dark brown translucent oil and the
remainder will be sour vinegar (Fig. 3).
Application
Blend with water in a ratio of 1:50 (1 liter wood vinegar and 50 liters water), or up to a ratio of 1:800 (1 liter
wood vinegar and 800 liters water). Spray it over plant shoots. Wood vinegar, like hormones, will be absorbed into twigs,
trunks, or leaves. Plants will be stronger, and leaves will be greener and resistant to pests and diseases.
Benefits
- 1. Farmers can produce wood vinegar from branches trimmed from trees.
- 2. Wood vinegar is safe to human beings, animals, plants, and environment.
- 3. Wood vinegar helps plants to grow better and stronger, and be resistant to pests and diseases.
- 4. Crop produce is high quality and safe.
- 5. Low cost of production attributed to savings from cost of chemicals.
Index of Images
Figure 1 Pile Wood in the Kiln.
Figure 2 (a) Put Tile at the Top of the Chimney. (B) the Steam Is Condensed into Liquid. (C) Collect the Vinegar Drops from the Bamboo or Plastic Pipe.
Figure 3 The Wood Vinegar.
Download the PDF. of this document, 298,793 bytes (292 KB).