We investigated the effects of hydrogen irradiation on the degree of linear polarization, rho, of the light emitted by site-controlled, dilute-nitride InGaAsN V-groove quantum wires (QWRs). While in the as-grown sample the polarization of the QWR emission is highly sensitive to the increasing temperature (T), after sample hydrogenation the value of rho remains nearly unchanged (and similar to 25%) for T <= 220 K. This observation-potentially important for the development of devices based on the QWR polarization-points to a larger energy separation between hole subbands in the hydrogenated QWRs, due to the strain increase associated with the H-induced passivation of nitrogen. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4758685]