Oxidized corn husks pulp fibres were more susceptible to be nanofibrillated than oat hulls pulp. Multiscale characterisation yielded an objective differentiation of the assessed CNF materials. The nanofibrillated corn husks pulp was homogeneous and had a minor fraction of residual fibres. AFM confirmed the structural homogeneity of the CNF having diameters less than 20 nm.