Juglans major

Juglans major (literally, the larger walnut), also known as Arizona walnut,^[1] is a walnut tree which grows to 50 ft tall (15 m) with a DBH of up to 0.61 metres (2 ft) at elevations of 300–2,130 m (1,000–7,000 ft) in Texas, Oklahoma, New Mexico, Arizona, and Utah.^[4] It also occurs in Mexico as far south as Guerrero.^[5] Common names include Arizona black walnut (as it belongs to the "black walnuts" section Juglans sect. Rhysocaryon), and the Spanish name nogal cimarrón (cimarron walnut).

Juglans major
At Morton Arboretum, Illinois
Conservation status
Least Concern  (IUCN 3.1)[1]
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Eudicots
Clade:	Rosids
Order:	Fagales
Family:	Juglandaceae
Genus:	Juglans
Section:	Juglans sect. Rhysocaryon
Species:	J. major
Binomial name
Juglans major (Torr.) A. Heller
Natural range of Juglans major
Synonyms[2][3]
Juglans elaeopyren Dode Juglans microcarpa subsp. major (Torr.) A.E. Murray Juglans microcarpa var. major (Torr.) L.D. Benson Juglans rupestris var. major Torr

Description

Arizona Walnut (Juglans major) nut and hulls

Arizona Walnut (Juglans major) nut cracked open showing nutmeat

In moister areas, the tree features a single, stout trunk; there are usually several slender trunks in drier situations.^[6] The 8–14 in long pinnately compound leaves bear 9–15 lanceolate leaflets, 19–32 mm (.75–1.25 in) wide by 51–102 mm (2–4 in) long. The small nut has a thick shell with deep grooves enclosing an oily, edible seed.^[7][8]

J. major grows primarily in canyons or riparian areas, near springs, and other areas with shallow groundwater. Where the range of J. major overlaps that of J. microcarpa, the two interbreed, producing many intermediate forms.^[9][10]