(This article is about the walnut tree. For other uses see Walnut (disambiguation).)

Walnut
Scientific classification
Kingdom: Plantae
Division: Magnoliophyta
Class: Magnoliopsida
Order: Juglandales
Family: Juglandaceae
Genus: Juglans
Species
  • Juglans ailanthifolia Carr. - Japanese walnut
  • Juglans boliviana Dode - Bolivian walnut
  • Juglans californica S. Wats. - California walnut
  • Juglans cinerea L. - butternut
  • Juglans hindsii Jepson - N. California walnut
  • Juglans jamaicensis C. DC. - West Indian walnut
  • Juglans major Heller - Arizona black walnut
  • Juglans microcarpa Berl. - little walnut
  • Juglans neotropica Diels - Andean walnut
  • Juglans nigra L. - black walnut
  • Juglans regia L. - Common walnut, English walnut
Hybrids
  • Juglans X bixbyi Rehd. - Bixby walnut
  • Juglans X intermedia Carr. - intermediate walnut
  • Juglans X quadrangulata Rehd.

Reference: [1]
as of 2003-03-13

The Walnut is any tree of the genus Juglans which belong to the walnut family, or Juglandaceae. Probably the two best-known members of the walnut family are the Common or Circassian walnut, Juglans regia, native of the region from southern Europe to the Himalaya, and also known as English walnut in the United States, and the American black walnut, Juglans nigra.

These two species are important for their attractive timber. Black walnut hulls are used as a dye source, yielding a rich brown color.

The nuts of all the species named above, as well as other species, are edible, but the walnuts commonly available in stores are the common walnut. A horticultural variety selected for hardiness in temperate zones is sometimes known as the Carpathian walnut.