Plantae > Tracheophyta > Magnoliopsida > Fagales > Juglandaceae > Juglans > Juglans regia

Juglans regia (English walnut)

Synonyms: Juglans arguta; Juglans asplenifolia; Juglans duclouxiana; Juglans fallax; Juglans fertilis; Juglans frutescens; Juglans fruticosa; Juglans heterophylla; Juglans intermedia; Juglans kamaonia; Juglans longirostris; Juglans orientis; Juglans praematuriens; Juglans regia subsp. sinensis; Juglans regia subsp. turcomanica; Juglans regia var. sinensis; Juglans salicifolia; Juglans sinensis; Pterocarya japonica; Regia maxima

Wikipedia Abstract

Juglans regia, Persian walnut, English 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. The largest forests are in Kyrgyzstan, where trees occur in extensive, nearly pure walnut forests at 1,000–2,000 m altitude—notably at Arslanbob in Jalal-Abad Province. It is widely cultivated across Europe.
View Wikipedia Record: Juglans regia


Height [3]  66 feet (20 m)
Width [3]  66 feet (20 m)
Air Quality Improvement [1]  Low
Allergen Potential [1]  High
Carbon Capture [1]  Medium
Screening - Summer [2]  Dense
Screening - Winter [2]  Porous
Shade Percentage [1]  91 %
Temperature Reduction [1]  Medium
Wind Reduction [1]  Medium-Low
Hardiness Zone Minimum [1]  USDA Zone: 5 Low Temperature: -20 F° (-28.9 C°) → -10 F° (-23.3 C°)
Hardiness Zone Maximum [1]  USDA Zone: 9 Low Temperature: 20 F° (-6.7 C°) → 30 F° (-1.1 C°)
Light Preference [6]  Mixed Sun/Shade
Soil Acidity [6]  Neutral
Soil Fertility [6]  Rich
Soil Moisture [6]  Mostly Dry
Water Use [1]  Moderate
Flower Color [2]  White
Foliage Color [2]  Green
Fruit Color [2]  Brown
Fruit Conspicuous [2]  Yes
Bloom Period [2]  Mid Spring
Drought Tolerance [2]  Medium
Edible [3]  May be edible. See the Plants For A Future link below for details.
Fire Tolerance [2]  Low
Flower Type [3]  Monoecious
Frost Free Days [2]  6 months 10 days
Fruit/Seed Abundance [2]  High
Fruit/Seed Begin [2]  Summer
Fruit/Seed End [2]  Fall
Growth Form [2]  Single Stem
Growth Period [2]  Spring, Summer
Growth Rate [2]  Rapid
Janka Hardness [4]  1210 lbf (549 kgf) Medium
Leaf Type [3]  Deciduous
Lifespan [5]  Perennial
Pollinators [3]  Wind
Propagation [2]  Bare Root, Container, Seed
Root Depth [2]  3.3 feet (102 cm)
Scent [3]  The bruised leaves have a pleasant sweet though resinous smell.
Seed Spread Rate [2]  Slow
Seed Vigor [2]  High
Seeds Per [2]  40 / lb (88 / kg)
Shape/Orientation [2]  Rounded
Specific Gravity [7]  0.47
Structure [3]  Tree
Usage [3]  A yellow dye is obtained from the green husks; It is green; The green nuts (is this the same as the green husks?) and the leaves are also used; The rind of unripe fruits is a good source of tannin; A brown dye is obtained from the leaves and mature husks; It does not require a mordant and turns black if prepared in an iron pot; The dye is often used as a colouring and tonic for dark hair; The leaves and the husks can be dried for later use; A golden-brown dye is obtained from the catkins in early summer. It does not require a mordant; A drying oil is obtained from the seed. It is used in soap making, paints, etc. It is not very stable and quickly goes rancid; The nuts can be used as a wood polish. Simply crack open the shell and rub the kernel into the wood to release the oils. Wipe off with a clean cloth; The dried fruit rind is used to paint doors, window frames etc[145] (it probably protects the wood due to its tannin content). The shells may be used as anti-skid agents for tyres, blasting grit, and in the preparation of activated carbon; The leaves contain juglone, this has been shown to have pesticidal and herbicidal properties; The crushed leaves are an insect repellent; Juglone is also secreted from the roots of the tree, it has an inhibitory effect on the growth of many other plants; Bark of the tree and the fruit rind are dried and used as a tooth cleaner. They can also be used fresh; Wood - heavy, hard, durable, close grained, seasons and polishes well. A very valuable timber tree, it is used for furniture making, veneer etc;
Vegetative Spread Rate [2]  None
View Plants For A Future Record : Juglans regia

Protected Areas

Name IUCN Category Area acres Location Species Website Climate Land Use
Bombay Hook National Wildlife Refuge VI 16363 Delaware, United States
Chippewa Nature Center   Michigan, United States    
Desecheo National Wildlife Refuge   Puerto Rico, United States
Kavkazskiy Biosphere Reserve Ia 692723 Krasnodar, Karachay-Cherkessia, Adygea, Russia
Luberon Regional Nature Park V 406572 France  
Palava Protected Landscape Area V   Czech Republic  
Parco Del Somma-Vesuvio e Miglio D'Oro National Park II 33648 Italy
Reserva de la Biosfera de Urdaibai Biosphere Reserve V 1777 Spain  


Abagrotis alternata (greater red dart)[8]
Aceria erinea[9]
Acherontia atropos (Death's-head hawk moth)[10]
Acrobasis caryae[8]
Acrobasis stigmella[8]
Acrocercops transecta[8]
Acronicta major[8]
Actias artemis[8]
Actias selene (Indian moon moth)[8]
Aglia tau (Tau Emperor)[8]
Ambulyx sericeipennis[8]
Amorpha juglandis (Walnut Sphinx)[8]
Amphipyra pyramidoides (copper underwing)[8]
Anastrepha bahiensis[11]
Anastrepha fraterculus (South American fruit fly)[11]
Aonidiella aurantii (California red scale)[12]
Archips argyrospila[8]
Archips podana (Large Fruit-tree Tortrix)[8]
Archips subsidiaria[8]
Argema besanti[8]
Argema mimosae (African moon moth)[8]
Auricularia auricula-judae (Jelly Ear)[13]
Biston regalis[8]
Caligula cachara[8]
Caligula japonica (Japanese Giant Silkworm)[8]
Caligula simla[8]
Calliteara pudibunda (Pale Tussock)[8]
Caloptilia juglandiella[8]
Caloptilia roscipennella[8]
Ceratocystis paradoxa[13]
Chaetoprocta odata (Walnut Blue)[8]
Characoma ruficirra[8]
Cheromettia apicata[8]
Chromaphis juglandicola (Walnut aphid)[10]
Citheronia splendens (Splendid Royal Moth)[8]
Clavaspis disclusa (decluse scale)[12]
Cossus cossus (Goat Moth)[8]
Crenulaspidiotus lahillei[12]
Crisicoccus matsumotoi[12]
Ctenopseustis obliquana[9]
Cydia pomonella (Codling moth)[8]
Cydia splendana (Chestnut Tortrix)[8]
Cytospora juglandina[13]
Daedaleopsis confragosa[13]
Datana integerrima (walnut caterpillar)[8]
Diaporthe juglandina[13]
Diaspidiotus aesculi (buckeye scale)[12]
Diaspidiotus ancylus (Howard scale)[12]
Diaspidiotus juglansregiae (English walnut scale)[12]
Diaspidiotus ostreaeformis (European fruit scale)[12]
Diaspidiotus perniciosus (California scale)[12]
Diaspidiotus zonatus[12]
Eacles penelope[8]
Ephestia parasitella[8]
Epiphyas postvittana (Light brown apple moth)[9]
Eriophyes erineus <Unverified Name>[10]
Eriophyes tristriatus <Unverified Name>[10]
Erschoviella musculana[8]
Eulecanium ciliatum (ciliate oak scale)[12]
Eulecanium excrescens (excrescent scale)[12]
Eulecanium kunoense (kuno scale)[12]
Eulecanium rugulosum[12]
Euproctis celebensis[8]
Euproctis chrysorrhoea (Brown-tail)[8]
Euzophera batangensis[8]
Euzophera bigella[8]
Euzophera osseatella[8]
Euzophera semifuneralis[8]
Fusicoccum juglandinum[13]
Ganoderma applanatum[13]
Gretchena concitatricana[8]
Hagapteryx mirabilior[8]
Hemiberlesia lataniae (latania scale)[12]
Hemiberlesia rapax (greedy scale)[12]
Lasiocampa trifolii (Grass Eggar)[10]
Leperisinus varius <Unverified Name>[10]
Lepidosaphes conchiformis (fig oystershell scale)[12]
Lepidosaphes malicola (Armenian comma hard scale)[12]
Lepidosaphes ulmi (apple oystershell scale)[12]
Lochmaeus manteo (Variable Oakleaf Caterpillar Moth)[8]
Lucanus cervus[10]
Lymantria obfuscata[8]
Macaca mulatta (rhesus monkey)[14]
Melanaspis inopinata[12]
Melanaspis tenebricosa (gloomy scale)[12]
Melanomma pulvis-pyrius[13]
Neopinnaspis harperi (Harper scale)[12]
Opogona xanthocrita[8]
Panaphis juglandis[10]
Paralipsa gularis (Stored nut moth)[8]
Parlatoria oleae (olive parlatoria scale)[12]
Perenniporia fraxinea[13]
Phanerochaete sordida[13]
Phleogena faginea[13]
Phyllonorycter juglandicola[8]
Planotortrix octo <Unverified Name>[9]
Plodia interpunctella (Indian meal moth)[8]
Prochoerodes forficaria[8]
Pseudaulacaspis pentagona (mulberry scale)[12]
Pseudococcus calceolariae (citrophilus mealybug)[12]
Pseudococcus maritimus (grape mealybug)[12]
Psittacula krameri (Rose-ringed Parakeet)[13]
Pulvinaria juglandii[12]
Pulvinaria regalis (horse chestnut scale)[12]
Pulvinaria vitis (cottony vine scale)[12]
Rhodinia newara[8]
Rhodococcus turanicus[12]
Salicicola archangelskyae (Archangelskaya scale)[12]
Saturnia pavonia (Emperor moth)[10]
Saturnia pyri (Great peacock moth)[8]
Sciurus carolinensis (eastern gray squirrel)[13]
Stauropus fagi (Lobster Moth)[8]
Synanthedon vespiformis (Yellow-legged Clearwing)[8]
Taphrorychus bicolor[10]
Teleiopsis brevivalva[8]
Thaumetopoea processionea (Pine processionary moth)[8]
Zeuzera pyrina (leopard moth)[8]


Parasitized by 
Aceria erinea[13]
Ceratocystis paradoxa[13]
Ganoderma applanatum (Artist’s Bracket)[13]
Helicotylenchus dihystera <Unverified Name>[15]
Inonotus hispidus (Shaggy Bracket)[13]
Mesorhabditis juglandicola <Unverified Name>[16]
Perenniporia fraxinea[13]


North America;



Attributes / relations provided by
1i-Tree Species v. 4.0, developed by the USDA Forest Service's Northern Research Station and SUNY-ESF using the Horticopia, Inc. plant database.
2USDA Plants Database, U. S. Department of Agriculture
3Plants For A Future licensed under a Creative Commons License
4Wood Janka Hardness Scale/Chart J W Morlan's Unique Wood Gifts
5PLANTATT - Attributes of British and Irish Plants: Status, Size, Life History, Geography and Habitats, M. O. Hill, C. D. Preston & D. B. Roy, Biological Records Centre, NERC Centre for Ecology and Hydrology (2004)
6ECOFACT 2a Technical Annex - Ellenberg’s indicator values for British Plants, M O Hill, J O Mountford, D B Roy & R G H Bunce (1999)
7Properties of Imported Tropical Woods, B. FRANCIS KUKACHKA, U.S. Department of Agriculture - Forest Service
8HOSTS - a Database of the World's Lepidopteran Hostplants Gaden S. Robinson, Phillip R. Ackery, Ian J. Kitching, George W. Beccaloni AND Luis M. Hernández
9New Zealand Institute for Plant & Food Research Plant-SyNZ™ database
10Biological Records Centre Database of Insects and their Food Plants
11Norrbom, A.L. 2004. Fruit fly (Tephritidae) host plant database. Version Nov, 2004.
12Ben-Dov, Y., Miller, D.R. & Gibson, G.A.P. ScaleNet 4 November 2009
13Jorrit H. Poelen, James D. Simons and Chris J. Mungall. (2014). Global Biotic Interactions: An open infrastructure to share and analyze species-interaction datasets. Ecological Informatics.
14Ecology of Rhesus Macaques (Macaca mulatta) in Northwest Pakistan, S. J. Goldstein and A. F. Richard, International Journal of Primatology, Vol. 10, No. 6, 1989, pp. 531-567
15Species Interactions of Australia Database, Atlas of Living Australia, Version ala-csv-2012-11-19
16Gibson, D. I., Bray, R. A., & Harris, E. A. (Compilers) (2005). Host-Parasite Database of the Natural History Museum, London
Protected Areas provided by Biological Inventories of the World's Protected Areas in cooperation between the Information Center for the Environment at the University of California, Davis and numerous collaborators.
Chippewa Nature Center
Natura 2000, UK data: © Crown copyright and database right [2010] All rights reserved. Ordnance Survey Licence number 100017955
Images provided by Google Image Search
Abstract provided by DBpedia licensed under a Creative Commons License
Weather provided by NOAA METAR Data Access