A simple technique for estimating above-ground biomass in short-rotation willow plantations

► Reliable estimates of willow biomass essential. ► LAI-2000 was used to calculate a 'stem area index' for relating to harvestable willow biomass. ► Willow clones used: Salix alba × Salix glatfelteri and Salix dasyclados. ► Measured stem area index was strongly related (r2 > 0.97; p < 0.05) to harvested willow biomass.