Biomass equations for hybrid larch growing on farmland

Johansson, T. 2011. Biomass equations for hybrid larch growing on farmland.Data were collected from 20 stands of hybrid larch (Larix x eurolepis) growing on abandoned farmland in southern and central Sweden (Lat. 55–60° N.). The mean stand age was 19 years (range 18–23). The mean number of stems per hectare was 1150 (range 364–2374) and the mean breast height diameter (over bark) was 15.6 cm (6.8–24.2). Soil types in the stands were light and medium clay and tills (sandy-silty and light clay).Mean dry weight above stump level (20 cm) for a hybrid larch tree in this study was 117 kg (range 36–245) and the standing dry weight for hybrid larch stands was 120 t ha−1 (42–350). Mean annual increment (MAI) for the tree was 6.09 kg y−1 (1.89–13.61) corresponding to production of 90–120 t ha−1 after 15–20 years growth and a stem number of 1000–1500, if the stand is mainly used for biomass. Alternatively, for pulp wood and timber production a rotation period of 30–40 years can be used, with thinnings being exploited for biomass.

► Hybrid larch could be planted on former farmland with a high future yield.
► Biomass equations for hybrid larch trees in Sweden were constructed.
► The mean dry mass above stump level was 117 kg d.w. tree−1.
► Biomass yields of 90–120 d.w. t ha−1 after 15–20 years growth are indicated.
► Timber, pulp wood and thinning harvests (biomass) could be practiced.