Significantly higher flexure properties (p < 0.0001) were observed for the Hurd–Hemp and Shive–Flax fiber-reinforced particleboards, a trend similar to that observed in the 100% Hurd and Shive particleboards from previous studies and attributed to their higher particle length to thickness ratios which enhanced bending strength and stiffness. Comparing these results to the MOR and MOE specifications outlined in ANSI A208.1-1999 and 2009, all the particleboard types exceeded the minimum values for both low and medium density M-2 grade particleboard with the exception of the MOR of the Wood-Hemp particleboards whose lower 5th percentile panel average based on ANSI A208.1-2009 fell below the stipulated standards.