  Propagating fronts arising from bistable reaction-diffusion equations are a
purely deterministic effect. Stochastic reaction-diffusion processes also show
front propagation which coincides with the deterministic effect in the limit of
small fluctuations (usually, large populations). However, for larger
fluctuations propagation can be affected. We give an example, based on the
classic spruce-budworm model, where the direction of wave propagation, i.e.,
the relative stability of two phases, can be reversed by fluctuations.
