UK POTENTIAL FOR SHORT-ROTATION FORESTRY FOR WOOD FUEL

Short-rotation forestry (SRF), in which fast-growing trees are cultivated and harvested between eight and 20 years after planting, appears to have potential as a source of renewable fuel for heat and power generation in Great Britain, according to a study undertaken by resource management consultants LTS International of Edinburgh for the Forestry Commission and Defra.

The study looked at 10 species of trees: four native species - alder, ash, birch and poplar; one naturalised species - sycamore; and five non-native species - three of Eucalyptus and two of southern beech. It examined the potential impacts of SRF on biodiversity, soils, hydrology, pests and diseases, archaeology and the landscape.

The report recommends:
- establishing a code of practice as to how growers could establish and manage their SRF crops in ways that would minimise such impacts.
- further research on three main areas: the growth rates and yields that might be achieved in Britain from SRF; the economics of SRF, particularly for the grower; and the water use of SRF stands.

The latter is of particular concern as the high water use by some species, particularly eucalypts, could threaten water supplies in certain parts of Britain. The report recommends that there should be clear guidance for land-use authorities and growers defining areas where SRF would not be acceptable.

'A Review of the Potential Impacts of Short Rotation Forestry' [February 2006. Final Report. P D Hardcastle/Review Team Leader] can be downloaded from the Forestry Commission website: http://www.forestry.gov.uk/pdf/SRFFinalreport27Feb.pdf/$FILE/SRFFinalreport27Feb.pdf
Or the Defra website: http://www.defra.gov.uk/farm/acu/energy/energy.htm .

FOOTNOTES:

Short-rotation forestry: the practice of cultivating fast-growing
trees that reach their economically optimum size between eight and 20 years old. Conventional forestry rotations in Britain vary between 40 and 150 years, depending on species. When felled, SRF trees are replaced by new planting or, more usually, allowed to regenerate from the stumps as coppice.

Short-rotation coppice (SRC): uses faster-growing tree species
such as willows and poplars that, after harvesting, sprout multiple new shoots from their stumps, that grow on to form the next crop in as little as three years. (Such practices have been used to produce ‘withies’ for basket-making for centuries).

Wood fuel: whether grown in SRF or SRC plantations or derived from traditionally managed woodland, could be used in different ways: in heating systems, electricity-generating plants or combined heat-and-power generating systems. Wood fuel is particularly suited to medium-sized buildings or groups of buildings that need a constant source of heat, such as schools, office blocks, factories, care homes, farms and hotels.

Sustainably grown biomass fuels: such as wood make only very small contributions to atmospheric carbon. The same amount of carbon that is released into the atmosphere when one crop is burned is reabsorbed by the plants grown for the next crop. The carbon emitted by the machinery used to establish, grow, harvest and transport the biomass is very small.