In plantation forests in parts of Europe, the

tree stump After a tree has been cut and felled, the stump or tree stump is usually a small remaining portion of the trunk with the roots still in the ground. Stumps may show the age-defining rings of a tree. The study of these rings is known as dendrochrono ...

s left after

felling Felling is the process of cutting down trees,"Feller" def. 2. and "Felling", def. 1. ''Oxford English Dictionary'' Second Edition on CD-ROM (v. 4.0) © Oxford University Press 2009 an element of the task of logging. The person cutting the trees ...

are now sometimes pulled out of the ground to supply

wood fuel Wood fuel (or fuelwood) is a fuel such as firewood, charcoal, Woodchips, chips, sheets, wood pellets, pellets, and sawdust. The particular form used depends upon factors such as source, quantity, quality and application. In many areas, wood is ...

for biomass power stations. The stump is the base of the trunk and the attached woody

root In vascular plants, the roots are the organs of a plant that are modified to provide anchorage for the plant and take in water and nutrients into the plant body, which allows plants to grow taller and faster. They are most often below the su ...

s. Tree stumps and roots are extracted using a hydraulic head on a tracked excavator or with a mechanical head equipped by a special tool for tractors. Stump harvesting is expected to provide an increasing component of the woody material required by the woody biomass power sector in Europe. Rotor stump grinder at work

Sustainability

Stump harvesting is unsuitable on many soils where the removal leads to long term reduction in nutrition or an unacceptable loss of soil carbon. Also, it is necessary that care is taken to avoid areas with archaeology, ecologically sensitive areas, steep slopes, and areas close to streams and rivers. In many situations removal of stumps leads to a further loss of wood with a resulting loss of the potential

biodiversity Biodiversity or biological diversity is the variety and variability of life on Earth. Biodiversity is a measure of variation at the genetic (''genetic variability''), species (''species diversity''), and ecosystem (''ecosystem diversity'') l ...

that depends on wood.

History

Stump harvesting is not a new process. Records of

s being dug out of the ground for wood fuel go back hundreds of years in Europe. It was practiced in the 1970s in Swedish forests before declining in popularity, but is being considered again there now that there is a greater need for fuel wood. In Britain, stumps are removed in some forests for disease control, especially in south-east England. Additionally, they are extracted where restoring plantation forest areas to peat bog for conservation reasons. Recently small scale commercial stump harvesting has started in parts of Scotland to provide fuel for biomass power stations. In Finland, stumps were at one time used to produce tar and charcoal. In the 1970s, a number of trials were set up in Finland to examine the viability of stump harvesting for woody biomass, but it is only in recent years that it has developed into a large scale commercial operation.

External links

Stump harvesting in SwedenRegeneration after stump harvestingStumps as a resource in FinlandSite selection and good practice for stump harvestingStump harvesting and forest decomposers

References

*Schenk, H.J., and R.B. Jackson. 2002. The global biogeography of roots. ''Ecological Monographs'' 72 (3): 311-328. *Staaf, H. and Olsson, B.A. 2004. Effects of slash removal and stump harvesting on soil water chemistry in a clearcutting in SW Sweden. ''Scandinavian Journal of Forest Research'' 9 (4): 305-310. *Sutton, R.F., and R.W. Tinus. 1983. Root and root system terminology. ''Forest Science Monograph 24'' pp 137. *Phillips, W.S. 1963. Depth of roots in soil. ''Ecology'' 44 (2): 424. {{DEFAULTSORT:Stump Harvesting Trees Forest management