Extracting and chipping hardwood crowns for energy.

Abstract This study investigated the feasibility of extracting and chipping hardwood crowns for energy after motor-manual thinning in stands of common beech. Large crowns were extracted and chipped from stands where only sawlogs had been produced, while small crowns were extracted and chipped from stands where sawlogs and firewood had been harvested. The fuel chip yield was 15 ha–1 when extracting and chipping large crowns, while it was 8 ha–1 when extracting and chipping small crowns. The productivity for extracting and chipping large crowns was 8.5 per workplace hour, and for small crowns was 5.9 per workplace hour. Extracting and chipping large crowns gave a net income of €167 ha–1 (€11 ), while extracting and chipping small crowns gave a lower net income of €23 ha–1 (€3 ). The study showed that extracting and chipping large hardwood crowns is feasible and can make a substantial contribution to woody biomass feedstocks. Four product-mix alternatives were considered, but the marginal differences in outc...