Wood tissue exhibits a hierarchical structure which provides structural support while enabling transport of water and nutrients . The microstructure is highly porous and varies extensively between species. Bulk transport of water and ions is effectively facilitated by the macroporosity of wood , however intra-cell wall diffusion requires infiltration into the complex assembly of lignocellulosic polymers. Quantitatively discerning the precise nanostructure of lignocellulosic biomass is still an active area of research ; however, it is generally accepted that bundles of several dozen cellulose chains are assembled into larger fibrils which are decorated with hemicellulose and further ensheathed with lignin , and that the internal structure and dynamics change as a function of hydration .