Radial particle transport is considered in a plasma with ergodic and stochastic flux lines. The self‐consistent electric field is neglected and the particle flux is due to a succession of mass convections along flux lines, in series with very small‐scale‐length transverse diffusion between neighboring flux lines. The dependence of the average radial flux on the thermodynamic forces, namely the pressure gradient that controls the parallel convection, and the density gradient that controls the small‐scale transverse diffusion is investigated. The conditions for which the average radial flux is driven by the average pressure or density gradient are derived.