Juglans regia, known by various common names including the common walnut, English walnut, or Persian walnut amongst other names, is a species of walnut. It is native to Eurasia in at least southwest a
Juglans nigra, the eastern American black walnut, is a species of deciduous tree in the walnut family, Juglandaceae, native to central and eastern North America, growing mostly in riparian zones.
Juglans regia
…called nogal de Castilla, suggesting the Mexicans associated the introduction of the tree into Mexico with Spaniards from Castile (as opposed to the black walnuts native to North America). The Old English term wealhhnutu is a late book-name (Old English Vocabularies, Wright & Wulker), so the remark that the…