Abstract
Herbarium specimens were collected of 648 plants during the inventory of plots to characterize the forest vegetation on Mount Wilhelm between 200 and 3700 m above sea level. Specimens are deposited mainly at LAE, MPU, P, and The New Guinea Binatang Research Centre. Nearly 93% have been identified to species or "morphospecies" level. The highest species richness diversity was observed among Rubiaceae, with 42 species. Although several botanical expeditions have already visited the site, at least fourteen potentially new species have been collected, showing that the flora of Mount Wilhelm, as that of Papua New Guinea in general, remains poorly known