The accelerating movement to restore wetlands, and especially to return flood plains to more natural conditions, leads to the widespread introduction and propagation of reeds and other forms of more-or-less flexible vegetation. These reeds and other types of vegetation then influence flows across wetlands, and the need to control flooding sequences and intensities using numerical models and other hydroinformatics tools necessitates a better understanding of this influence of flexible vegetation on flows. A numerical model is introduced that serves as a means for investigating the influence of the several factors that contribute to flow resistance induced by flexible vegetation. The model has been partially calibrated from data obtained in experiments with inflexible vegetation.