  In his comment, Riemann defends the conventional kinetic Bohm criterion on
the basis that the underlying approximations become rigorous in the limit
\lambda_D/l \rightarrow 0, where \lambda_D is the Deybe length and l is a
collision length scale for the dominant collision process. Here, we expand on
our previous arguments showing that the basic assumptions for the justified use
of the conventional kinetic Bohm criterion are typically not satisfied in
laboratory plasmas. We corroborate our argument with experimental data, as well
as data from numerical simulations, showing that the conventional criterion is
violated in common situations. In contrast, a formulation based on positive
velocity moments of the kinetic equation provides a criterion that both agrees
with the experimental data and reduces to the traditional expectations from
fluid theory in the appropriate limit.
