Plantae > Tracheophyta > Magnoliopsida > Fagales > Juglandaceae > Juglans > Juglans nigra

Juglans nigra (black walnut)

Synonyms: Juglans pitteursii; Wallia nigra

Wikipedia Abstract

Juglans nigra, the eastern black walnut, is a species of deciduous tree in the walnut family, Juglandaceae, native to eastern North America. It grows mostly in riparian zones, from southern Ontario, west to southeast South Dakota, south to Georgia, northern Florida and southwest to central Texas. Wild trees in the upper Ottawa Valley may be an isolated native population or may have derived from planted trees.
View Wikipedia Record: Juglans nigra


Height [3]  98 feet (30 m)
Width [3]  66 feet (20 m)
Air Quality Improvement [1]  Low
Allergen Potential [1]  High
Carbon Capture [1]  Medium-High
Screening - Summer [2]  Porous
Screening - Winter [2]  Porous
Shade Percentage [1]  91 %
Temperature Reduction [1]  Medium-High
Wind Reduction [1]  Medium
Hardiness Zone Minimum [1]  USDA Zone: 4 Low Temperature: -30 F° (-34.4 C°) → -20 F° (-28.9 C°)
Hardiness Zone Maximum [1]  USDA Zone: 9 Low Temperature: 20 F° (-6.7 C°) → 30 F° (-1.1 C°)
Light Preference [2]  Full Sun
Soil Acidity [2]  Neutral
Soil Fertility [2]  Very Rich
Water Use [1]  Moderate
Flower Color [2]  Yellow
Foliage Color [2]  Green
Fruit Color [2]  Brown
Fruit Conspicuous [2]  Yes
Bloom Period [2]  Late Spring
Drought Tolerance [2]  Low
Edible [3]  May be edible. See the Plants For A Future link below for details.
Fire Tolerance [2]  High
Flower Type [3]  Monoecious
Frost Free Days [2]  5 months 20 days
Fruit/Seed Abundance [2]  Low
Fruit/Seed Begin [2]  Fall
Fruit/Seed End [2]  Fall
Growth Form [2]  Single Stem
Growth Period [2]  Spring
Growth Rate [2]  Rapid
Hazards [3]  The plant has occasionally been known to cause contact dermatitis in humans;
Janka Hardness [4]  1010 lbf (458 kgf) Soft
Leaf Type [3]  Deciduous
Lifespan [2]  Perennial
Pollinators [3]  Wind
Propagation [2]  Bare Root, Container, Cutting, 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]  Erect
Specific Gravity [5]  0.55
Structure [3]  Tree
Usage [3]  A brown dye is obtained from the nuts, husks and bark; It does not require a mordant; The husks can be dried for later use; A brown dye is obtained from the leaves and stems; It does not require a mordant; The dye turns black if it is prepared in an iron pot; The leaves can be dried for later use; The husks are rich in tannin; The green fruit husks can be boiled to provide a yellow dye; The husks can be made into a high quality coal (does the report mean charcoal?; It was used in gas masks; The woody shells on the fruits have been used to make jewellery; Insects are said to avoid the walnut tree, hence it is often used as a poor man's insect repellent. When rubbed on faces, walnut leaves are said to repel flies; The leaves repel fleas and have been used as a strewing herb; They are also used as an insecticide against bed bugs; The ground up husks are also insecticidal; The leaves produce substances that depress the growth of other plants. These substances are washed onto the ground by rain and inhibit the growth of plants beneath the tree; The roots also produce substances that are toxic to many plant species, especially apples (Malus species), members of the Ericaceae, Potentilla spp and the white pines (certain Pinus spp.); An alternative ingredient of 'QR' herbal compost activator; This is a dried and powdered mixture of several herbs that can be added to a compost heap in order to speed up bacterial activity and thus shorten the time needed to make the compost; Wood - very ornamental, heavy, hard, strong, close-grained, very durable. Easily worked, it glues well, does not warp, shrink or swell much and takes a good polish. It weighs 38lb per cubic foot. A very valuable timber tree and possibly the most sought after wood in N. America, it is used in cabinet making, the interior finishes of houses, furniture, airplanes, ship building, veneer etc;
Vegetative Spread Rate [2]  None
View Plants For A Future Record : Juglans nigra

Protected Areas

Name IUCN Category Area acres Location Species Website Climate Land Use
Allegheny Portage Railroad Nat'l Hist. Site National Historic Site III 1152 Pennsylvania, United States
Appomattox Court House National Historical Park V 1687 Virginia, United States
Assateague Island National Seashore II 8621 Maryland, United States
Big South Fork National River and Recreation Area National Recreation Area V 120283 Kentucky, Tennessee, United States
Blue Ridge Parkway National Parkway V 73611 North Carolina, Virginia, United States
Bluestone National Scenic River National River and Wild and Scenic Riverway V 3517 West Virginia, United States
Booker T. Washington National Monument V 237 Virginia, United States
Calvin College Ecosystem Preserve 90 Michigan, United States
Carolinian-South Atlantic Biosphere Reserve 310228 North Carolina, South Carolina, Georgia, United States      
Catoctin Mountain Park National Park II 5994 Maryland, United States
Central Gulf Coastal Plain Biosphere Reserve 40530 United States  
Chesapeake & Ohio Canal National Hist. Park National Historical Park V 19586 Maryland, District of Columbia, United States
Chickamauga & Chattanooga Nat'l Military Park National Military Park V 8248 Georgia, Tennessee, United States
Colonial National Historic Park National Historical Park V 9316 Virginia, United States
Coweeta Hydrologic Laboratory LTER Site Long Term Ecological Research   North Carolina, United States
Cumberland Gap National Hist. Park National Historical Park V 24282 Kentucky, Tennessee, Virginia, United States
Edwin S. George Reserve 1297 Michigan, United States
Felsenthal National Wildlife Refuge VI 66133 Arkansas, United States
Fort Donelson National Battlefield III 560 Tennessee, United States
Fort Larned National Historic Site III 706 Kansas, United States
Fort Necessity National Battlefield III 1019 Pennsylvania, United States
Fredericksburg and Spotsylvania Nat'l Military Park National Military Park V 10384 Virginia, United States
Friendship Hill National Historic Site III 697 Pennsylvania, United States
Gateway National Recreation Area V 1807 New Jersey, United States
Gauley River National Recreation Area V 10157 West Virginia, United States
George Washington Birthplace National Monument V 435 Virginia, United States
George Washington Memorial Parkway V   Virginia, United States
Gettysburg National Military Park V 3560 Pennsylvania, United States
Grand Rapids Audubon Club Maher Sanctuary 80 Michigan, United States
Great Smoky Mountains National Park II 515454 North Carolina, Tennessee, United States
Great Swamp National Wildlife Refuge VI 3161 New Jersey, United States
Harpers Ferry National Historical Park VI 715 West Virginia, United States
Herbert Hoover National Historic Site   Iowa, United States
Hobcaw Barony (North Inlet) National Estuarine Research Reserve 7585 South Carolina, United States
Homestead National Monument of America V 850 Nebraska, United States
Hopewell Furnace National Historic Site III 861 Pennsylvania, United States
Horseshoe Bend National Military Park V 1926 Alabama, United States
Indiana Dunes National Lakeshore II 8272 Indiana, United States
Kennesaw Mountain National Battlefield Park III 2897 Georgia, United States
Little River National Wildlife Refuge   Oklahoma, United States
Mammoth Cave Area Biosphere Reserve (Natn'l Park) National Park II 51235 Kentucky, United States
Morristown National Historical Park VI 1677 New Jersey, United States
New River Gorge National River National River and Wild and Scenic Riverway V 55591 West Virginia, United States
Niagara Escarpment Biosphere Reserve 470167 Ontario, Canada  
Obed Wild and Scenic River National River and Wild and Scenic Riverway V 5268 Tennessee, United States
Oconee National Forest Botanical Reserve 306 Georgia, United States  
Palava Protected Landscape Area V   Czech Republic  
Petersburg National Battlefield III 3338 Virginia, United States
Pipestone National Monument V 326 Minnesota, United States
Point Pelee National Park II 5764 Ontario, Canada
Reserva de la Biosfera de Urdaibai Biosphere Reserve V 1777 Spain  
Richmond National Battlefield Park III 1517 Virginia, United States
Rock Creek Park   District of Columbia, United States
Rondeau Provincial Park II 5035 Ontario, Canada
Roosevelt Vanderbilt National Historic Site   New York, United States      
Saint Lawrence Islands National Park II   Ontario, Canada
Saratoga National Historical Park   New York, United States
Shenandoah National Park II 108221 Virginia, United States
Shiloh National Military Park III 4061 Tennessee, United States
South Atlantic Coastal Plain Biosphere Reserve 20317 South Carolina, United States  
Southern Appalachian Biosphere Reserve 37548505 North Carolina, Tennessee, United States  
Spivey Pond Management Area 54 California, United States      
Tennessee River Gorge   Tennessee, United States
Upper Miss. River Nat'l Wildlife Refuge National Wildlife Refuge VI 25823 Illinois, Iowa, Wisconsin, United States
Valley Forge National Historical Park VI 3509 Pennsylvania, United States
Western Michigan University's Asylum Lake Preserve 274 Michigan, United States


Abagrotis alternata (greater red dart)[6]
Acrobasis angusella[6]
Acrobasis caryivorella[6]
Acrobasis demotella (Walnut shoot moth)[6]
Acrobasis indigenella[6]
Acrobasis juglandis (Pecan leaf casebearer)[6]
Acrobasis juglanivorella[6]
Acrobasis latifasciella[6]
Acrocercops transecta[6]
Acronicta afflicta (Afflicted Dagger Moth)[6]
Acronicta impleta (Yellow-haired Dagger Moth)[6]
Actebia fennica (black army cutworm)[6]
Actias luna (luna moth)[6]
Allotria elonympha (False Underwing Moth)[6]
Alsophila pometaria (fall cankerworm)[6]
Amorpha juglandis (Walnut Sphinx)[6]
Baileya dormitans[6]
Caloptilia blandella[6]
Caloptilia juglandiella[6]
Cameraria caryaefoliella[6]
Catocala californica[6]
Chionaspis caryae (hickory scurfy scale)[7]
Chionaspis furfura (Harris's bark-louse)[7]
Citheronia splendens (Splendid Royal Moth)[6]
Coleophora laticornella (pecan cigar casebearer)[6]
Colocasia propinquilinea (Closebanded Yellowhorn)[6]
Coptomma lineatum[8]
Crocigrapha normani[6]
Cydia caryana (Hickory Shuckworm Moth)[6]
Cydia pomonella (Codling moth)[6]
Dasychira cinnamomea[6]
Datana angusii[6]
Datana contracta (Contracted Datana)[6]
Datana integerrima (walnut caterpillar)[6]
Diaspidiotus ancylus (Howard scale)[7]
Dichomeris ligulella (Palmerworm)[6]
Elaphria versicolor (Variegated Midget)[6]
Ephestia elutella (Tobacco moth)[6]
Euproctis chrysorrhoea (Brown-tail)[6]
Eutrapela clemataria[6]
Euzophera semifuneralis[6]
Gretchena bolliana (Pecan Bud Moth)[6]
Hemiberlesia rapax (greedy scale)[9]
Heterocampa umbrata[6]
Homohadena infixa[6]
Hylesinus crenatus[9]
Hypagyrtis unipunctata (One-spotted Variant Moth)[6]
Lecanodiaspis prosopidis[7]
Lochmaeus manteo (Variable Oakleaf Caterpillar Moth)[6]
Nemoria bistriaria (Red-fringed Emerald)[6]
Neopinnaspis harperi (Harper scale)[7]
Nites betulella[6]
Oemona hirta[8]
Orthosia garmani[6]
Orthosia revicta[6]
Paleacrita vernata (spring cankerworm)[6]
Parallelia bistriaris (Maple Looper Moth)[6]
Parthenolecanium putmani[7]
Phigalia titea (Spiny Looper)[6]
Phobetron pithecium (hag moth)[6]
Prolimacodes badia (Skiff Moth)[6]
Pseudaulacaspis pentagona (mulberry scale)[7]
Pyrrhia umbra (Bordered Sallow)[6]
Sabulodes caberata (Omnivorous looper)[6]
Satyrium calanus (Banded hairstreak)[6]
Schizura leptinoides[6]
Sciurus niger (eastern fox squirrel)[10]

Range Map

North America; Western Michigan University’s Asylum Lake;



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
5Forest Inventory and Analysis DB version 5.1, May 4, 2013, U.S. Forest Service
6HOSTS - a Database of the World's Lepidopteran Hostplants Gaden S. Robinson, Phillip R. Ackery, Ian J. Kitching, George W. Beccaloni AND Luis M. Hernández
7Ben-Dov, Y., Miller, D.R. & Gibson, G.A.P. ScaleNet 4 November 2009
8New Zealand Institute for Plant & Food Research Plant-SyNZ™ database
9Biological Records Centre Database of Insects and their Food Plants
10Geographic variation in walnut seed size correlates with hoarding behaviour of two rodent species, N. Tamura and F. Hayashi, Ecol Res (2008) 23: 607–614
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.
Calvin College Ecosystem Preserve
Edwin S. George Reserve, University of Michigan, Department of Ecology and Evolutionary Biology
Maher Sanctuary, Grand Rapids Audubon Club
Western Michigan University’s Asylum Lake
Images provided by Google Image Search
Abstract provided by DBpedia licensed under a Creative Commons License
Weather provided by NOAA METAR Data Access