Interesting Facts
Description
Family Juglandaceae
Trees
or rarely shrubs
, deciduous, semievergreen, or evergreen
, monoecious or rarely dioecious; bark
tight (or exfoliating) . Branchlets
with solid or chambered
pith
. Terminal
buds subglobose or ovoid
to oblong
, naked or with scales
. Stipules absent. Leaves alternate (or opposite), odd- or even-pinnate, sometimes trifoliolate
, rarely simple
; leaflets
with glandular
, peltate scales, often resinous
and aromatic
, particularly conspicuous
abaxially on young leaves and twigs
, margin
serrate or rarely entire. Inflorescences pendulous or sometimes erect
, lateral
or terminal, on reduced shoots
arising on branchlets of previous year (old growth) or on current
year’s growth (new growth), of several types: androgynous panicle with male, lateral spikes and female, central spike; androgynous panicle with male, mainly lateral spikes and female, central spike male at apex; cluster
of male spikes and solitary female spike; or solitary male and female spikes. Flowers unisexual
, anemophilous
, rarely entomophilous. Male flowers subtended by an entire or 3-lobed bract; bracteoles 2 or absent; sepals 0-4, adnate
to receptacle when present; stamens 3-40(-100), inserted
on receptacle; filaments
short to nearly absent, free
or united
at base
; anthers
glabrous
or pubescent
, 2-loculed, dehiscing longitudinally. Female flowers with an entire or 3-lobed bracts; bracteoles 2 or 3 (or absent) ; sepals 0-4, adnate to ovary, free at apex; gynoecium of 2 carpels united into an inferior ovary
, 1-loculed, but at base 2-4(-8) -loculed; style 1, short or elongate
, rarely absent; stigmas 2, carinal or commissural
, sometimes 4-lobed, plumose
or fleshy
; ovule 1, orthotropous
. Fruiting spike elongate, and pendulous or short and erect, rarely conelike. Fruit a drupelike nut, 2-4(-8) -chambered at base, with a dehiscent
or indehiscent husk
, or a 2- or 3-winged or disc-winged nutlet
. Seed solitary, without endosperm. Cotyledons 4-lobed, much contorted. Germination hypogeal or epigeal. 2n = (28), 32, (64) .
Nine genera and 60 or more species: mostly in temperate
and subtropical
regions of the N hemisphere; seven genera (one endemic) and 20 species (seven endemic, one introduced
) in China.[1]
Genus Juglans
Shrubs
or trees
, 3-50 m.
Bark
light to dark gray or gray-brown, smooth
or split into ridges
or plates
. Twigs
purplish brown, terete
, stout, sparsely to densely covered with glands
and capitate-glandular hairs
, sometimes also with scales
or fasciculate hairs, early in season
with multiradiate
hairs; leaf scars
triangular or 3-lobed, large; pith
chambered
. Bud scales valvate
, densely hirsute
. Leaves usually odd-, sometimes even-pinnate; petiole
and rachis with indument
as twigs. Leaflets
5-25, sessile or subsessile
, often aromatic
, uniform
in size or median
leaflets largest, (2.5-) 4.3-15(-17.5) × 0.8-6.5 cm; surfaces usually with nonglandular hairs (simple
and/or fasciculate), glandular
hairs, sessile glands, and/or scales, sometimes glabrous
. Staminate
catkins solitary from 2d-year twigs, sessile; stamens 7-50 per flower, glabrous or pilose
. Pistillate
flowers solitary or in terminal
racemes
. Fruits nuts enclosed in husks
, not compressed
; husks thick, indehiscent; nuts tan, neither compressed nor angled
, grooved
, ridged
, rugulose
, or smooth; shells
thick. Seeds sweet. x
= 16.
Species 21: North America, Mexico, West Indies, Central America, South America, Eurasia
.
Juglans is a very important source of edible nuts, dyes, and wood
for cabinet work, furniture, and construction. Juglans regia Linnaeus, the walnut of commerce, is widely cultivated in California; it is easily distinguished from native species
by its leaves with 5-11 broad, entire leaflets and nuts with thin rugulose shells, not grooved or ridged. Because of its sensitivity to native
pathogens
, J. regia is usually grown as stem-grafts on roots
of native or hybrid walnuts (see discussion under J. hindsii). Occasional seedlings of J. regia have been reported from the vicinity of cultivated plants
, but these seldom, if ever, live to maturity.
The growth form
, bark, and fruit are important taxonomically in Juglans, but these usually are not available on herbarium
specimens. As with many woody plants
, the first one or two leaves of the season (i.e.
, the lowermost leaves on the twig
) are sometimes atypical
in structure, having broader, blunter leaflets. The fasciculate hairs on the veins normally have more rays than those on the blade
. In addition to the types of hairs described below, small multiradiate hairs are found on the immature
twigs, petioles, rachises, and midribs
. They are usually gone when the leaf is fully expanded, but they may persist for a short time afterwards.[2]
Taxonomy
- Domain:
Eukaryota
(
)
- Whittaker & Margulis,1978
- eukaryotes
- Kingdom:
Plantae
(
)
- Haeckel, 1866
- Plants
- Subkingdom:
Viridaeplantae
(
)
- Cavalier-Smith, 1981
- Phylum:
Tracheophyta
(
)
- Sinnott, 1935 ex Cavalier-Smith, 1998
- Vascular Plants
- Subphylum:
Euphyllophytina
(
)
- Infraphylum:
Radiatopses
(
)
- Kenrick & Crane, 1997
- Class:
Spermatopsida
(
)
- Brongniart, 1843
- Subclass:
Rosidae
(
)
- Takhtajan, 1967
- Superorder:
Juglandanae
(
)
- Takhtajan Ex Reveal, 1992
- Order:
Fagales
(
)
- Engler, 1892
- Family:
Juglandaceae
(
)
- DC. ex Perleb, 1818, nom. cons.
- walnuts
- Subfamily:
Juglandoideae
(
)
- Tribe:
Juglandeae
(
)
- Genus:
Juglans
(
)
- C. Linnaeus, 1753
- Walnut
- Specific epithet:
sigillata
- Dode
- Botanical name: - Juglans sigillata Dode
- Specific epithet:
sigillata
- Dode
- Genus:
Juglans
(
- Tribe:
Juglandeae
(
- Subfamily:
Juglandoideae
(
- Family:
Juglandaceae
(
- Order:
Fagales
(
- Superorder:
Juglandanae
(
- Subclass:
Rosidae
(
- Class:
Spermatopsida
(
- Infraphylum:
Radiatopses
(
- Subphylum:
Euphyllophytina
(
- Phylum:
Tracheophyta
(
- Subkingdom:
Viridaeplantae
(
- Kingdom:
Plantae
(
Notes
Publishing author : Dode Publication : Bull . Soc. Dendrol. France 1906, 94.
Similar Species
Members of the genus Juglans
ZipcodeZoo has pages for 82 species, subspecies, varieties, forms, and cultivars in this genus:
J. ailanthifolia (Japanese Walnut) · J. ailanthifolia var. cordiformis (Heartnut) · J. ailantifolia (Japanese Walnut) · J. australis (Nogal Criollo) · J. bixbyi (Bixby Walnut) · J. boliviana (Bolivian Walnut) · J. californica (Northern California Black Walnut) · J. californica S.Watson var. californica S.Watson (Southern California Black Walnut) · J. californica var. californica (California Walnut) · J. cinerea (Butternut) · J. cinerea 'Bountiful' (Butternut) · J. cinerea 'Loumis' (Butternut) · J. cordiformis 'Campbell Cw1' (Heartnut) · J. cordiformis 'Campbell Cw3' (Heartnut) · J. cordiformis 'Campbell Cww' (Heartnut) · J. cordiformis 'Frank' (Heartnut) · J. cordiformis 'Imshu' (Heartnut) · J. cordiformis 'Locket' (Heartnut) · J. cordiformis 'Marvel' (Heartnut) · J. cordiformis 'Mitchell Hybrid' (Heartnut) · J. cordiformis 'Rhodes' (Heartnut) · J. cordiformis 'Simcoe' (Heartnut) · J. cordiformis 'Stealth' (Heartnut) · J. cordiformis 'Wright' (Heartnut) · J. hindsii (Northern California Black Walnut) · J. illinoinensis (Pecan) · J. intermedia (Intermediate Walnut) · J. jamaicensis (Walnut) · J. major (Arizona Black Walnut) · J. mandshurica (Manchurian Walnut) · J. microcarpa (Little Walnut) · J. microcarpa var. microcarpa (Little Walnut) · J. microcarpa var. stewartii (Stewarts Little Walnut) · J. microcarpa var. stewartii (I.M.Johnst.) W.Manning (Stewart's Little Walnut) · J. microcarpa subsp. major (Little Walnut) · J. neotropica (Andean Walnut) · J. nigra (Black Walnut) · J. nigra 'Beineke 11' (Black Walnut 'beineke 11') · J. nigra 'Black Gem' (Black Walnut) · J. nigra 'Daniels' (Black Walnut) · J. nigra 'Emma Kay' (Black Walnut) · J. nigra 'Football 2' (Black Walnut) · J. nigra 'Krause' (Black Walnut) · J. nigra 'Kwik Krop' (Black Walnut) · J. nigra 'Laciniata' (Black Walnut) · J. nigra 'Lamb's Curly' (Black Walnut) · J. nigra 'Ridgeway' (Black Walnut) · J. nigra 'Rowher' (Black Walnut) · J. nigra 'Sauber 1' (Black Walnut) · J. nigra 'Schrieber' (Black Walnut) · J. nigra 'Sparrow' (Black Walnut) · J. nigra 'Surprise' (Black Walnut) · J. nigra 'Thomas Black' (Black Walnut) · J. nigra 'Thomas Myers' (Black Walnut) · J. regia (Carpathian Walnut) · J. regia var. Carpathian (Carpathian Walnut) · J. regia 'Allegheny' (Carpathian Walnut) · J. regia 'Bedco 1' (Carpathian Walnut) · J. regia 'Broadview' (Dwarf English Walnut) · J. regia 'Cascade' (Carpathian Walnut) · J. regia 'Champion' (Carpathian Walnut) · J. regia 'China-B' (Carpathian Walnut) · J. regia 'Coble #2' (Carpathian Walnut) · J. regia 'Colby' (Carpathian Walnut) · J. regia 'Greenhaven' (Carpathian Walnut) · J. regia 'Hansen' (Carpathian Walnut) · J. regia 'Kaiser' (Carpathian Walnut) · J. regia 'Ky Giant' (Carpathian Walnut) · J. regia 'Lake' (Carpathian Walnut) · J. regia 'Looking Glass' (Carpathian Walnut) · J. regia 'Mckinster' (Carpathian Walnut) · J. regia 'Northern Prize' (Carpathian Walnut) · J. regia 'Perry' (Carpathian Walnut) · J. regia 'Purpurea' (Carpathian Walnut) · J. regia 'Reda' (Carpathian Walnut) · J. regia 'S-1' (Carpathian Walnut) · J. regia 'Shiawassee' (Carpathian Walnut) · J. regia 'Somers' (Carpathian Walnut) · J. regia 'Utah Giant' (Carpathian Walnut) · J. × bixbyi (Bixby Walnut) · J. x intermedia (Intermediate Walnut) · J. 'Royal' (Walnut)
More Info
- Search for Pictures: images.google.com
- Search for Scholarly Articles: Google Scholar
- Search using Scientific Name and Vernacular Names: All the Web | AltaVista Canada | AltaVista | Excite | Google | HotBot | Lycos
- Search using Specialized Databases: GenBank | Medline | Scirus | CISTI/CAL | Agricola Periodicals | Agricola Books
Further Reading
- Plantae Wilsonianae; an enumeration of the woody plants collected in western China for the Arnold arboretum of Harvard university during the years 1907, 1908, and 1910, by E. H. Wilson, ed. by Charles Sprague Sargent. Cambridge, University Press, 1913-17. url p. 184, p. 613.
- Sargent, C. S. Plantae Wilsonianae: an enumeration of the woody plants collected in western China for the Arnold arboretum of Harvard university during the years 1907, 1908, and 1910 /by E. H. Wilson, ed. by Charles Sprague Sargent. 3 1917 Cambridge: The University press, 1913-17. url p. 184.
- Kuang Ko-zen & Lu An-ming. 1979. Juglandaceae. In: Kuang Ko-zen & Li Pei-chun, eds., Fl. Reipubl. Popularis Sin. 21: 6-44.
- McGranahan, G. H. and P. B. Catlin. 1987. Juglans rootstocks. In: R. C. Rom and R. F. Carlson, eds. 1987. Rootstocks for Fruit Crops. New York. Pp. 411-450.
Notes
Contributors
- Brands, S.J. (comp.) 1989-present. The Taxonomicon. Universal Taxonomic Services, Zwaag, The Netherlands. Accessed January 10, 2012.
Data Sources
Accessed through GBIF Data Portal March 05, 2008:
- Missouri Botanical Garden
Identifiers
- Biodiversity Heritage Library NamebankID: 5840906
- Globally Unique Identifier: urn:lsid:ipni.org:names:442436-1
- International Plant Names Index (IPNI) ID: 442436-1
- Zipcode Zoo Species Identifier: 2126909
Footnotes
- Anmin Lu, Donald E. Stone & L. J. Grauke "Juglandaceae". in Flora of China Vol. 4 Page 277. Published by Science Press (Beijing) and Missouri Botanical Garden Press. Online at EFloras.org. [back]
- Alan T. Whittemore & Donald E. Stone "Juglans". in Flora of North America Vol. 3. Oxford University Press. Online at EFloras.org. [back]
