Internal bond strength of Flax and Hemp fiber-reinforced particleboards: Wood-Hemp (W–H), Wood–Flax (W–F), Hurd–Hemp (H–H) and Shive–Flax (S–F). Horizontal line indicates minimum value stipulated by ANSI A208.1-1999. n = 32 for each mean. Error bars represent least significant difference for each mean. Means with the same letters are not significantly different at ˛= 0.05.