Pollen grains of Celtis tala (Celtidaceae), Phytolacca dioica (Phytolaccaceae), Schinopsis balansae (Anacardiaceae) and Solidago chilensis (Asteraceae) are examined with light and scanning electron microscopy, described, and illustrated. These four unrelated species are native to southern South America and considered an important source of skin prick allergy tests. Most relevant pollen characters are compared to those of their closest relatives. Celtis tala (3-, 4-, or 5- porate, verrucate) shares characters with the Celtis africana type in lacking a sunken area around the ora and in having the sculptural elements regularly arranged; Phytolacca dioica (3-colpate) with the Phytolacceae type in being microechinate and microperforate; Schinopsis balansae (3-colporate, striato-reticulate) with some members of the Lithraea molleoides subtype (Anacardiaceae) in having high muri and long striae; Solidago chilensis (3-colporate, echinate) with the Solidago type in being caveate. This study contributes to a better understanding of pollen morphology in species that are especially common to southern South America.