Juglans x Paradox (Paradox Black Walnut)

Paradox Walnuts are crossbreeds of Juglans hindsii and Juglans regia. They are midway between the parents in leaf shape and bark colour, are relatively variable, and can only be identified from other regia–black walnut hybrids by molecular methods. Leaflets are common, along with squarish, thick-shelled, weakly grooved nuts. These robust hybrids produce good wood but provide modest nut yields. They are frequently planted as shade trees in California and occasionally further north along the Pacific coast. Paradox seedlings are hybrids of black and English walnuts; the rootstocks are grown by nurseries using seed nuts collected from black walnut trees pollinated by English walnut pollen.