Charcoal Making – A Wood Collier’s Story
Speaker: John & Christine Westcott
Date: 23rd February
Christine & John talking to Chairman Liam Hutchings after the talk
John and Christine’s talk provided an insight into making charcoal, one of the Three Copse Woodland products made by the Westcott family business, which is based at Little Hyden Wood in Clanfield. https://www.threecopse.co.uk
Christine gave the talk and spoke firstly about the history of charcoal and charcoal making.
- 8000 years ago our ancestors discovered that the chard remains in the embers of their fires were good for drawing on walls. Then technology moved on and pit kilns were developed for firing pottery using charcoal. It was subsequently found that charcoal burns hotter than wood and was useful for smelting metals, copper, tin and bronze and iron for tools and weapons, iron being a hard metal could be worked to produce a good sharp edge. A metal working industry developed in the Weald in south-eastern England. Cutting down of the Wealden woodland worried John Evelyn and Jonathan Swift in the 17th Century. They were afraid the all the trees would disappear, however coppicing was introduced which saved the day! By then coke was found to be better than charcoal for the metal industry so it moved up North.
- The next development was the Earth Burn, where a heap of cut wood was stacked around a central chimney and covered with earth or damp straw. Fire lighters were tipped down the chimney to set the burn going and kept at the right rate until it was ready; then about 40 gallons of water would be poured down the chimney and when the process was finished it would be raked out in concentric circles from the outside.
- The Metal Ring Kiln came next in the 19th Century, it was faster and less trouble than the Earth Burn and only took two days. The Westcott business uses ring kilns. The process involves leveling, setting the vents, loading the charge of wood, kindling and “brown ends” in concentric circles in a dome. The kiln is then fired after a pre burn and a lid placed on it and the bottom blocked off. There are six vents, three for air in and three for smoke out. After the firing has finished, charcoal is produced with some brown ends.
- Retort Kilns are now taking over, gases are recycled into the fire and no wood is burnt. Half metre lengths of wood are stacked in the chamber, the gases keep the heat going, and some venting keeps the temperature right. It is cleaner and faster than a ring kiln, it takes 10 to 15 hours, uses less wood and the result is larger charcoal.
- Christine then went on to discuss some uses of charcoal, Large amounts are made commercially, for Barbeques; purification of water(takes out organics); air and medicine; in the garden and blacksmithing. Activated charcoal has fine grains, with a large surface area to absorb organics. It is used in cooker hoods, gas-mantles and air purifiers. Medical uses include charcoal pills and it absorbs poisons. As a farming supplement it absorbs methane from cows. Biochar + fertilizer. Biochar-fertilizer combinations have a better performance than pure fertilizers, in terms of yield and plant nutrition. Bigger beetroot! It also locks up carbon which is good for the environment. In the garden it can be added to compost or manure water. It provides a catalyst for further chemical reactions and thatching bars for Thatchers. It is used under the grass at Wimbledon.
- Management of the woodland also helps the environment. Christine told us they have 13/14 acres of woodland and coppice hazel every 5/7 years. They keep some tall trees mainly ash, they don’t coppice the ash that looks sound – leaving it to seed. They have some ash die back. Coppicing leads to more flowers (which appear after coppicing), fruit, nuts and insects, birds, bats and mammals. It provides a changing habitat for wildlife and in particular is good for the Silver Washed Fritillary butterfly. The emerging 20 odd rods on the stools grow fast as they use up carbon dioxide from the air. Some of the coppiced woodland can be several hundred years old. The stools can be 20 ft in diameter.
The Woodland industry provide employment for rural workers and Coppice Groups have a professional body to turn to namely the National Coppice Federation https://ncfed.org.uk
Christine and John were happy to answer our questions to round off this very interesting talk.