Suitable forestry machines for mechanical fuel load reduction and salvage recovery: a short review

Forest fires are one of the most severe incidents that can destroy large areas of forest lands and cause substantial damages to the nearby residential areas and farmlands. Human efforts to reduce the likelihood of starting forest fires include prescribed burning, mechanical fuel load reduction and livestock grazing. Following natural disasters in forest areas, a salvage recovery operation is usually conducted that may cause some environmental impacts. This article aimed to review the literatures to provide a summary of different types of machines and working methods that have been studied in different countries. The review results showed that the most common method for mechanical fuel load reduction was mechanised cut-to-length using a harvester and a forwarder. This method has been widely applied in Canada, USA, Europe, and Oceania. In some countries (e.g. Australia and USA) the whole tree method is also applied for mechanical fuel load reduction. This method was often conducted using feller-bunchers, grapple skidders and chippers/grinders. The majority of mechanical fuel load reduction projects produced the extra fibre which could be used for bioenergy purposes. The number of salvage recovery studies was limited compared with studies on mechanical fuel load reduction. Salvage recovery operations applied a cut-to-length and whole tree harvesting methods. Windthrown trees were extracted to the roadside using heavy size forwarders or grapple skidders in flat/moderate terrains while tower yarders were applied in steep terrains. Detailed information on work productivity is described in this article which can be of use to the academic and industrial users.