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Juglans regia Broadview.jpg
Juglans regia
Scientific classification Red Pencil Icon.png
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Rosids
Order: Fagales
Family: Juglandaceae
DC. ex Perleb [1]
Type genus

See text

Engelhardioideae Distribution.svg
The range of subfamily Engelhardioideae
Juglandoideae Distribution.svg
The range of subfamily Juglandoideae
Synonyms [2]
  • Platycaryaceae Nakai ex Doweld
  • Pterocaryaceae Nakai, nom. inval.
  • Rhoipteleaceae Hand.-Mazz. 1932, nom. cons.

The Juglandaceae are a plant family known as the walnut family. They are trees, or sometimes shrubs, in the order Fagales. Members of this family are native to the Americas, Eurasia, and Southeast Asia.


The nine or ten genera in the family have a total of around 50 species, [3] and include the commercially important nut-producing trees walnut (Juglans), pecan (Carya illinoinensis), and hickory (Carya). The Persian walnut, Juglans regia , is one of the major nut crops of the world. Walnut, hickory, and gaulin are also valuable timber trees while pecan wood is also valued as cooking fuel.


Members of the walnut family have large, aromatic leaves that are usually alternate, but opposite in Alfaroa and Oreomunnea . The leaves are pinnately compound or ternate, and usually 20–100 cm long. The trees are wind-pollinated, and the flowers are usually arranged in catkins.

The fruits of the Juglandaceae are often confused with drupes but are accessory fruit because the outer covering of the fruit is technically an involucre and thus not morphologically part of the carpel; this means it cannot be a drupe but is instead a drupe-like nut. [4]


The known living genera are grouped into subfamilies, tribes, and subtribes as follows: [5]


Modern molecular phylogenetics suggest the following relationships: [7]

Myricaceae  (outgroup)














Related Research Articles

Fagales Order of flowering plants

The Fagales are an order of flowering plants, including some of the best-known trees. The order name is derived from genus Fagus, beeches. They belong among the rosid group of dicotyledons. The families and genera currently included are as follows:

Drupe Fleshy fruit with hard inner layer (endocarp or stone) surrounding the seed

In botany, a drupe is an indehiscent fruit in which an outer fleshy part surrounds a single shell of hardened endocarp with a seed (kernel) inside. These fruits usually develop from a single carpel, and mostly from flowers with superior ovaries.

Fagaceae Family of flowering plants

Fagaceae is a family of flowering plants that includes beeches and oaks, and comprises eight genera with about 927 species. Fagaceae in temperate regions are mostly deciduous, whereas in the tropics, many species occur as evergreen trees and shrubs. They are characterized by alternate simple leaves with pinnate venation, unisexual flowers in the form of catkins, and fruit in the form of cup-like (cupule) nuts. Their leaves are often lobed and both petioles and stipules are generally present. Their fruits lack endosperm and lie in a scaly or spiny husk that may or may not enclose the entire nut, which may consist of one to seven seeds. In the oaks, genus Quercus, the fruit is a non-valved nut called an acorn. The husk of the acorn in most oaks only forms a cup in which the nut sits. Other members of the family have fully enclosed nuts. Fagaceae is one of the most ecologically important woody plant families in the Northern Hemisphere, as oaks form the backbone of temperate forest in North America, Europe, and Asia and one of the most significant sources of wildlife fodder.

<i>Juglans</i> Genus of trees

Walnut trees are any species of tree in the plant genus Juglans, the type genus of the family Juglandaceae, the seeds of which are referred to as walnuts. All species are deciduous trees, 10–40 metres (33–131 ft) tall, with pinnate leaves 200–900 millimetres (7.9–35.4 in), with 5–25 leaflets; the shoots have chambered pith, a character shared with the wingnuts (Pterocarya), but not the hickories (Carya) in the same family.

Pecan Species of hickory native to the southern USA and northern Mexico

The pecan is a species of hickory native to the southern United States and northern Mexico in the region of the Mississippi River. The tree is cultivated for its seed in the southern United States, primarily in Georgia, New Mexico, Texas, and Mexico, which produces nearly half of the world total. The seed is an edible nut used as a snack and in various recipes, such as praline candy and pecan pie. The pecan, in various aspects, is included in state symbols of Alabama, Arkansas, California, Oklahoma, and Texas.

Nut (fruit) Dry and edible seed, that usually has a high fat content

A nut is a fruit consisting of a hard or tough nutshell protecting a kernel which is usually edible. In general usage and in a culinary sense, a wide variety of dry seeds are called nuts, but in a botanical context "nut" implies that the shell does not open to release the seed (indehiscent).

Hickory Genus of trees

Hickory is a common name for trees composing the genus Carya, which includes around 18 species. Five or six species are native to China, Indochina, and India (Assam), as many as twelve are native to the United States, four are found in Mexico, and two to four are native to Canada. A number of hickory species are used for products like edible nuts or wood.

<i>Pterocarya</i> Genus of trees

Pterocarya, often called wingnuts in English, are trees in the walnut family Juglandaceae. They are native to Asia. The botanic name is from Ancient Greek πτερον (pteron) "wing" + κάρυον (karyon) "nut".

<i>Juglans regia</i> Species of tree (walnut)

Juglans regia, the Persian walnut, English walnut, Carpathian walnut, Madeira walnut, or especially in Great Britain, common walnut, is an Old World walnut tree species native to the region stretching from the Balkans eastward to the Himalayas and southwest China. It is widely cultivated across Europe.

Putranjivaceae Family of trees

Putranjivaceae is a rosid family that is composed of 218 species in 2 genera of evergreen tropical trees that are found mainly in the Old World tropics, but with a few species in tropical America.

<i>Carya ovata</i> Species of tree

Carya ovata, the shagbark hickory, is a common hickory in the Eastern United States and southeast Canada. It is a large, deciduous tree, growing well over 100 ft (30 m) tall, and can live more than 350 years. The tallest measured shagbark, located in Savage Gulf, Tennessee, is over 150 ft (46 m) tall. Mature shagbarks are easy to recognize because, as their name implies, they have shaggy bark. This characteristic is, however, only found on mature trees; young specimens have smooth bark.

Juglandeae Tribe of flowering plants

Juglandeae is a tribe of the Juglandoideae subfamily, in the Juglandaceae family. Walnut tree species comprise the Juglans genus, which belong to the Juglandeae tribe.

Nyctaginaceae Family of flowering plants

Nyctaginaceae, the four o'clock family, is a family of around 33 genera and 290 species of flowering plants, widely distributed in tropical and subtropical regions, with a few representatives in temperate regions. The family has a unique fruit type, called an "anthocarp", and many genera have extremely large pollen grains.

Annamocarya is a genus of flowering plants in the family Juglandaceae, containing only one species, Annamocarya sinensis, native to southwestern China and northern Vietnam. It is related to the hickories, and was formerly included in the same genus Carya, as Carya sinensis, but also shares a number of characteristics with the walnuts in the genus Juglans. It is grouped with Carya in the subtribe Caryinae. It is sometimes called Chinese hickory or beaked hickory.

Juglandoideae Subfamily of flowering plants

Jugandoideae is a subfamily of the walnut family Juglandaceae.

Caryinae Subtribe of flowering plants

Caryinae is a subtribe of the tribe Juglandeae subfamily in the Juglandaceae.

<i>Curculio caryae</i> Species of beetle

The pecan weevil, Curculio caryae is an obligate feeder on the nuts of North American hickories and pecans, most widely recognized as an economically important pest of the pecan, Carya illinoinensis. It has also been observed to infest one Juglans species, the Persian walnut, Juglans regia.

<i>Carya pallida</i> Species of flowering plant

Carya pallida, sand hickory, or pale hickory is a species of hickory native to the southeastern United States. It is a perennial, dicotyledonous plant which prefers rocky or sandy habitats. The sand hickory can reach heights of up to 30m, but its typical height is between 9-24m. In an open area, Carya crowns are usually towering and slim. The sand hickory nut is edible and consumed by various organisms.


  1. Angiosperm Phylogeny Group (2009). "An update of the Angiosperm Phylogeny Group classification for the orders and families of flowering plants: APG III" (PDF). Botanical Journal of the Linnean Society. 161 (2): 105–121. doi: 10.1111/j.1095-8339.2009.00996.x . Retrieved 2013-07-06.
  2. "Family: Juglandaceae DC. ex Perleb, nom. cons". Germplasm Resources Information Network. United States Department of Agriculture. 2003-01-17. Archived from the original on 2015-10-03. Retrieved 2011-11-17.
  3. Christenhusz, M. J. M.; Byng, J. W. (2016). "The number of known plants species in the world and its annual increase". Phytotaxa. 261 (3): 201–217. doi: 10.11646/phytotaxa.261.3.1 .
  4. John Derek Bewley, Michael Black, Peter Halmer (2006) The Encyclopedia of Seeds: Science, Technology And Uses
  5. Manos, P. S.; D. E. Stone (2001). "Evolution, phylogeny and systematics of the Juglandaceae" (PDF). Annals of the Missouri Botanical Garden. 88 (2): 231–269. doi:10.2307/2666226. JSTOR   2666226.
  6. "GRIN Genera of Juglandaceae". Germplasm Resources Information Network. United States Department of Agriculture. Archived from the original on 2015-09-24. Retrieved 2011-11-17.
  7. Xiang XG, Wang W, Li RQ, Lin L, Liu Y, Zhou ZK, Li ZY, Chen ZD (2014). "Large-scale phylogenetic analyses reveal fagalean diversification promoted by the interplay of diaspores and environments in the Paleogene". Perspectives in Plant Ecology, Evolution and Systematics. 16 (3): 101–110. doi:10.1016/j.ppees.2014.03.001.