Mate is a traditional tea from south america it is brewed from the leaves and stem of the ilex paraguariensis tree which is a species of the holly family exposed to flames after harvesting the tea has a refreshing taste with a slightly smoky flavour mate is a traditional tea from south america it is brewed from the leaves and stem of the ilex paraguariensis tree which is a species of the holly family exposed to flames after harvesting the tea has a refreshing taste with a slightly smoky f