Juglans nigra, black walnut Family: Juglandaceae Pollen grain morphology: perioporate, heteropolar, aspidate pores Pollen grain size: 36.31 + 0.84 µm by 34.58 + 1.08 µm April 29, 2015juglandaceae, Uncategorizedaspidate pores, black walnut, heteropolar, juglandaceae, juglans, nigra, periporate