Short review of collecting technologies and methods in forest harvesting residues recovery

Tree felling and processing can create harvesting residues including leaves and twigs (needles), cones, barks, and branches. Collecting forest harvesting residues requires application of suitable machines and working methods. This article is aimed at reviewing the published reports to identify new harvesting machines and working methods for recovering harvesting residues and the current gaps. The scope of review included published research reports/articles from 2017 to 2022 (last five years). This global review results showed that popular methods for residue collection are chipping residues at roadside/landing and integrated biomass recovery. Forwarder, cable yarder and in-field chipper are predominantly applied within various recovery methods depending on ground and stand conditions. Harvesting residues are one of the promising sources for bioenergy production which requires developing efficient and low-cost harvesting systems. Latest research findings indicate that piling harvesting residues by a harvester-pro-cessor can improve the collecting productivity by the forwarder within cut-to-length harvesting opera-tions. Integrating residue biomass recovery with conventional timber supply can reduce the total supply chain cost by 2%. Researchers also recommend applying more climate-friendly technologies and focus-ing on developing new machines with lower fuel consumption and subsequent emissions. Future studies can focus on the following subjects; a) to determine the productivity and cost rates of various residue recovery systems, b) to develop and test technologies with lower fuel consumption rates and c) to find in-novative solutions to utilize thinning materials and best practices to store and process biomass materials.