Pollen morphology of a total of 40 taxa of Rhododendron and its closely related genera of the tribe Rhodoreae, Rhododendron (34 spp.), Therorhodion (2 spp.) and Menziesia (4 spp.), was examined by means of light microscopy (LM) and scanning electron microscopy (SEM), or SEM alone (Table 1). The pollen tetrads of R. japonicum, R. schlippenbachii, R. tsusiophyllum and M. pentandra were examined with transmission electron microscopy (TEM) to study the exine stratification of respective genera