  We study the effect of including a BGK collisional kernel on the collective
modes of a QCD plasma which has a hard-particle distribution function which is
anisotropic in momentum space. We calculate dispersion relations for both the
stable and unstable modes and show that the addition of hard particle
collisions slows the rate of growth of QCD plasma unstable modes. We also show
that for any anisotropy there is an upper limit on the collisional frequency
beyond which no instabilities exist. Estimating a realistic value for the
collisional frequency for alpha_s ~ 0.2 - 0.4 we find that for the
large-anisotropy case which is relevant for the initial state of matter
generated by free streaming in heavy-ion collisions that the collisional
frequency is below this critical value.
