''Juglans mandshurica'', also known as Manchurian walnut or tigernut, is a species of

deciduous In the fields of horticulture and botany, the term deciduous () means "falling off at maturity" and "tending to fall off", in reference to trees and shrubs that seasonally shed Leaf, leaves, usually in the autumn; to the shedding of petals, aft ...

tree in the walnut family,

Juglandaceae 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 ...

. It is native to East Asia.

Description

The tree grows to about . The

leaves A leaf (: leaves) is a principal appendage of the stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, ...

are alternate, long, odd-pinnate, with 7–19 leaflets, long and broad (margin serrate or serrulate, apex acuminate). The male

flower Flowers, also known as blooms and blossoms, are the reproductive structures of flowering plants ( angiosperms). Typically, they are structured in four circular levels, called whorls, around the end of a stalk. These whorls include: calyx, m ...

s are in drooping catkins long, the wind-pollinated female flowers (April–May) are terminal, in spikes of 4 to 10, ripening in August–October into nuts, , with densely glandular pubescent green husk and very thick shell. The Manchurian walnut contains and exudes much lesser quantities of

allelopathic Allelopathy is a biological phenomenon by which an organism produces one or more biochemicals that influence the germination, growth, survival, and reproduction of other organisms. These biochemicals are known as allelochemicals and can have ben ...

compounds (such as

juglone Juglone, also called 5-hydroxy-1,4-naphthalenedione (IUPAC) is a phenolic organic compound with the molecular formula C10H6O3. In the food industry, juglone is also known as C.I. Natural Brown 7 and C.I. 75500. It is insoluble in benzene but s ...

) than other popular ''Juglans'' species and usually causes few significant allelopathic effects in cultivation.

Taxonomy

This species was first described by the Russian botanist Carl Johann Maximowicz in 1856. ''Juglans cathayensis'', characterized by tomentose leaflets, producing more flowers per spike and growing south of the

Yellow River The Yellow River, also known as Huanghe, is the second-longest river in China and the List of rivers by length, sixth-longest river system on Earth, with an estimated length of and a Drainage basin, watershed of . Beginning in the Bayan H ...

, was sometimes recognized as a species separate from ''J. mandshurica''. The Japanese walnut is listed by some authorities as ''Juglans mandshurica'' var. ''sachalinensis'' (syn. ''

Juglans ailantifolia ''Juglans ailantifolia'' (synonyms ''J. cordiformis'' and ''J. sieboldiana'' and '' J. mandshurica'' var. ''sachalinensis''), the Japanese walnut (), is a species of walnut native to Japan and Sakhalin. Description It is a deciduous tree growi ...

'').

Distribution and habitat

The species is native to the Eastern Asiatic Region (China, Russian Far East, North Korea and South Korea). The tree is exceptionally

hardy Hardy may refer to: People * Hardy (surname) * Hardy (given name) * Hardy (singer), American singer-songwriter Places Antarctica * Mount Hardy, Enderby Land * Hardy Cove, Greenwich Island * Hardy Rocks, Biscoe Islands Australia * Hardy, ...

(down to at least −45 °C), has a relatively short vegetation period compared to other walnuts, grows rapidly and is cultivated as an

ornamental Ornamental may refer to: *Ornamental grass, a type of grass grown as a decoration *Ornamental iron, mild steel that has been formed into decorative shapes, similar to wrought iron work *Ornamental plant, a plant that is grown for its ornamental qua ...

in colder temperate regions all over the Northern Hemisphere. For example, it has been found to grow satisfactorily in

Edmonton Edmonton is the capital city of the Provinces and territories of Canada, Canadian province of Alberta. It is situated on the North Saskatchewan River and is the centre of the Edmonton Metropolitan Region, which is surrounded by Central Alberta ...

Alberta Alberta is a Provinces and territories of Canada, province in Canada. It is a part of Western Canada and is one of the three Canadian Prairies, prairie provinces. Alberta is bordered by British Columbia to its west, Saskatchewan to its east, t ...

, Canada.

Uses

The kernels of the nuts are edible, but small and difficult to extract. The timber is in use, but less valuable than that of

English walnut ''Juglans regia'', known by various common names including the common walnut, English walnut, or Persian walnut amongst other names, is a species of Juglans, walnut. It is native to Eurasia in at least southwest and central Asia and southeast ...

black walnut ''Juglans nigra'', the eastern American black walnut, is a species of deciduous tree in the walnut family, Juglandaceae, native to central and eastern North America, growing mostly in riparian zones. Black walnut is susceptible to thousand can ...

References

External links

Juglans mandshurica
@ Flora of China {{Taxonbar, from=Q311361 mandshurica Flora of China Trees of Korea Flora of Russia Trees of Russia Trees of continental subarctic climate Fruit trees Taxa named by Karl Maximovich