ABSTRACT
Colonization of freshly-fallen leaves by buoyant propagules of aero-aquatic fungi was demonstrated by introducing Acer saccharum leaves onto the surface of a small heterotrophic woodland pond. Subsequent degree of colonization by Hormiactis ontariensis, Beverwykella pulmonaria, Pseudoaegerita matsushimae and Helicodendron triglitziense was significantly correlated with duration of stay on the water surface. The substrate preferences of these fungi were also investigated. Pseudoaegerita matsushimae and H. ontariensis sporulated more frequently on freshly-abscised, than on year-old A. saccharum and Fagus grandifolia leaves. Beverwykella pulmonaria and H. triglitziense sporulated more frequently on year-old Acer saccharum leaves than on freshly-abscised leaves of the same species. P. matsushimae, H. ontariensis and H. triglitziense all sporulated more frequently on freshly-abscised than on year-old F. grandifolia leaves while B. pulmonaria exhibited no age preference.