Traditional Coppice vs Willow Coppice
Yields of fire wood vary massively between different species of tree that are often thought of as fast growing. For example Ash, an ideal firewood, might produce 5 tonnes of fire wood from a hectare of land (2.5 acres) per year once established whereas willow planted as SRC willow could produced 12 tonnes from the same land area. Willow SRC is the fastest tree crop grown for wood fuel in the UK. Ash won't typically be harvested for fire wood until 20 years after planting, willow can be harvested within 3 years, but you may want to wait 6 year if you are after larger diameter logs.
Poplar can be grown in a similar way to willow and will give larger diameter logs more quickly. Unlike willow poplar tends to produce only a small number of new shoots when coppiced.
The table below gives indicative yields for different ways of growing wood fuel and fire wood, but bear in mind that even the official figures from the likes of the Forestry Commission etc have a margin of error of 30% even when growing conditions are know!
Different Fire Wood Yield from different woodland management systems
|
Tonnes per hectare (2.47 acres) per year |
Typical Farm woodland (unmanaged) |
2-3 tonnes |
Traditional mixed coppice |
4-5 tonnes |
Short Rotation Coppice Willow |
8-12 tonnes |
Short Rotation Coppice Poplar |
4-20 tonnes, yields for Poplar have not proven consistent in the UK, but can do very well. |