  The effects of large scale mechanical forcing on the dynamics of rotating
turbulent flows are studied by means of numerical simulations, varying
systematically the nature of the mechanical force in time. We demonstrate that
the statistically stationary solutions of these flows depend on the nature of
the forcing mechanism. Rapidly enough rotating flows with a forcing that has a
persistent direction relatively to the axis of rotation bifurcate from a
non-helical state to a helical state despite the fact that the forcing is
non-helical. We find that the nature of the mechanical force in time and the
emergence of helicity have direct implications on the cascade dynamics of these
flows, determining the anisotropy in the flow, the energy condensation at large
scales and the power-law energy spectra that are consistent with previous
findings and phenomenologies under strong and weak-wave turbulent conditions.
