Charcoal was once the major product of coppice woodlands, iron works used Oak charcoal, gunpowder manufacture utilised charcoal from Alder and Lime, and domestic fire places used small coles produced from other species. Massive stakes of wood as large as 24 foot in diameter were covered with earth and sod. These huge kilns know as earth clamps would be charred in one burn over 4 or 5 days, and required continuos attention from workers known as wood colliers.

These days, charcoal is mostly produced in steel kilns and mainly utilises poor quality wood in order supplement the income derived from more profitable woodland activities.

When wood is converted into charcoal it weight is reduced by 80%, its economic value however, can increase by a factor of five. The traditional method of producing charcoal, using earth clamps, is laborious and dirty work, which requires constant monitoring and adjustment. Modern steel kilns are somewhat less demanding but require a significant capital investment (unless you make them yourself).

Charcoal is best produced on site using mature hardwood coppice (approx. twenty years old). Charcoal burning should be integrated into the overall management of a woodland, using only the wood that cannot be utilised in more profitably crafts and products.

The process takes about 72 hours, so it saves time and is more profitable to use two kilns so that one can be loaded or unloaded while the other is burning and cooling. There needs to be plenty of seasoned firewood available as there is no point in having to transport it to the kiln.

Using two modern, portable steel kilns it would be possible to complete twelve burns in a month and produce about four tons of charcoal. This would need to be sieved and graded before being weighed and bagged for sale.

Further reading:

• W. Llyod Lakeland Charcoal, a report from the New Woodmanship Trust to the Lake District National Park,1987
• R.Tabor Traditional Woodland Crafts, 1994