Juglans microcarpa subsp. major (Torr.) A.E. Murray
Juglans microcarpa var. major (Torr.) L.D. Benson
Juglans rupestris var. major Torr
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" sectionJuglans sect. Rhysocaryon), and the Spanish name nogal cimarrón (cimarron walnut).
Description
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]
^Laferriere, J.E. (1993). "Juglandaceae, Walnut Family". Journal of the Arizona-Nevada Academy of Science 27:219.
^Kershner, Mathews, Nelson, and Spellenberg (2008). National Wildlife Federation Field Guide to Trees of North America Inc, New York: Sterling Publishing Co., p. 228.
^Heller, Amos Arthur. (1909). Muhlenbergia; a Journal of Botany 1(4): 50.
^Torrey, John. (1853). Report of an Expedition down to the Zuni and Colorado Rivers 171, pl. 16.
^Vines, Robert A. (1960). Trees, shrubs, and woody vines of the Southwest. Austin, TX: University of Texas Press. 1104 p
^Powell, A. Michael. (1988). Trees & shrubs of Trans-Pecos Texas including Big Bend and Guadalupe Mountains National Parks. Big Bend National Park, TX: Big Bend Natural History Association. 536 p.