The ability of Coulomb friction to drag minor ions out of the subsonic region of the low corona is examined analytically. With some assumptions, we obtain new analytical expressions for the 'minimum proton flux' that is required to drag minor ions out of the corona and for the velocity, relative to the protons, at which the minor ions are dragged out. We use these new results to suggest that the positive n&agr;/np versus &ugr;p correlation and the negative n&agr;/np versus np&ugr;p correlation observed for solar wind helium at 1 AU are due to variations in the temperature of the low corona: hotter coronal regions produce solar wind flows that are slower but that have a greater proton flux density relative to cooler coronal regions, but because of the temperature dependence of the Coulomb friction the hotter coronal regions result in smaller values of n&agr;/np at 1 AU. We also suggest that the charge dependence of the Coulomb friction may lead to errors in determining the coronal temperature from measurements of the ionization state at 1 AU.