Thermal softening, or thermo-activated viscoelasticity, is involved in several industrial and/or traditional craftsmanship techniques processing of wood. More fundamentally, it represents a very useful probe of chemical differences and/or of physical histories of wood samples [1,2,3,4,5]. Thermal softening of wet (= water-saturated) wood occurs at much lower temperature than that of completely (anhydrous) dried wood [6,7]. Softening of oven-dry wood happens at temperatures above 150°C, a temperature level at which wood amorphous polymers start to degrade [3,8]. Therefore, the characterisation of wet wood is the unique method that allows thermal softening to be distinguished from thermal degradation.