Extractable phenolic yield variation in five cultivars of mature short rotation coppice willow from four plantations in Quebec

Short rotation coppice willow (Salix sp.) is well established as an effective phytoremediation crop and is also emerging as an attractive lignocellulosic bioenergy option. The prospect of integrating value-added renewable chemicals as a supplementary component of the crop's value is explored here in terms of absolute phenolic yields, extractable from field cultivated mature biomass. Five willow cultivars, selected as leading biomass yielding cultivars, were cultivated at four field sites in Quebec, Canada: Salix x dasyclados 'SV1', Salix viminalis 'SV5027', Salix miyabeana 'SX61', 'SX64', 'SX67'. Substantial and significant cultivar variation was observed in groups of compounds including hydroxycinnamic acids and derivatives, benzoic acids derivatives, flavonols and condensed tannins in concentration per ton of biomass and/or yield per hectare per year. The highest phenolic yields were produced by Salix miyabeana 'SX67' cultivated at St-Roch at 5.43 (±0.60) kg ha−1 yr−1, which also produced 35.54 (±4.10) kg ha−1 yr−1 condensed tannins. These phenolic yields suggest further exploration of renewable chemicals production as a supplement to other biomass end-uses could be worthwhile. Such flexibility would help provide important advantages for weathering renewables policy and market uncertainty as well as improve the feasibility and competitiveness of sustainable biomass production as part of an integrated green technology platform.