  I consider two cases where QCD string is described by an effective theory of
long strings: the static potential and meson scattering amplitudes in the Regge
regime. I show how they can be solved in the mean-field approximation,
justified by the large number of space-time dimensions, and argue that it turns
out to be exact. I compare contributions from QCD string and perturbative QCD
and discuss experimental consequences for the scattering amplitudes.
