Harvesting of stumps for fuel

A new type of fuel, the stumps, has been developed by the side of forest energy in Finland during the past five years.The use of stumps has increased especially at the plants, which have acquires an on-site crusher. The spruce-dominant final cutting areas, from which the logging residues have first been harvested, form the best target for excavation of the stumps. Soil tillage, required by the regeneration of forests, is combined with stump excavation. The stumps form an enormous energy source, the share of the stumps in spruce predominant areas correspond to 25-30 % of the volume of the stems. The energy content of the spruce stumps, harvested from the best sites, corresponds to 150-200 MWh/ha, being more than the energy content of the logging residues harvested from the corresponding area. In addition to this the harvesting of stumps prevents the spreading of e.g. the root-rot fungi into the next tree generation.