These epibenthic mats were patchy and developed primarily in the wetlands with high and intermediate water-recession rates but were limited in the low-recession wetland, with cattail shade, anaerobic conditions, and substrates consisting of organic matter (τc of 5.6Pa), bare soil (3.0Pa), and muck (1.8Pa). Small inflows sustained ponding and associated cattails, which promoted shade and destabilized the surface soil of the low-recession system, as well as subareas within the better-drained wetlands. Epibenthic mats played an unexpected, disproportionate role in soil stabilization compared to vascular plants.