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Black Walnut Juglans nigra

Phonetic Spelling
JOO-glanz NY-gruh
This plant has low severity poison characteristics.
See below
Description

Juglans nigra, commonly known as Black Walnut as the nuts and husks can make a dark stain, is an extremely valuable and attractive forest tree. It is a member of the walnut family (Juglandaceae) and is native to a broad swath of central and eastern North America. It grows well on rich bottom lands, in moist, fertile coves, and on lower slopes throughout North Carolina. The species epithet is Latin for "black."

Black Walnut prefers moist, organically rich, well-drained soils in full sun. It prefers full sun and wet to dry loam or sandy high acidic to slightly alkaline soil. Its survival, growth, and quality in less fertile sites is problematic. It is intolerant of shade. This massive tree with a 50 to 90 foot height and a 3 to 6 foot diameter trunk when mature. It has an upright spreading open form, with an ovid crown and a tall trunk, and very deep taproot making it difficult to transplant.  It has the habit of losing its lower branches to begin its spread at 20 feet above the ground.  Both male and female flowers are on each tree (monoecious); males take the form of 2 to 4 inch long catkins with 17 to 50 stamens and female flowers forming on the end of stalks bearing fruit in October. It may be grown for its edible nuts. Nut production can sometimes begin as early as 6 years but usually takes 20 years for a substantial crop. 

Its tree's leaves, stems and roots contain juglone, which inhibits the growth of some plants beneath the tree's dripline. Plants known to be sensitive to juglone include azaleas, peonies, and some fruits and vegetables, like tomatoes, apples, and blueberries,  

The nuts are edible but difficult to remove from the husk, and the fleshy husk can be used as a dye. Once used by Native Americans medicinally, the tree is a scarce, native hardwood used in furniture and veneer.

It is a host plant for the larvae of the Hickory horndevil (Citheronia regalis) moth.

Diseases, Insects, and Other Plant Problems:

Under pressure in some areas from thousand cankers disease. Other potential diseases include anthracnose, bacterial blight, root rot, canker, leaf spot and shoot dieback. Watch for aphids, fall webworm and a variety of foliage chewing caterpillars. Nuts can be messy in fall. Occasionally known to cause contact dermatitis in humans.

Habitat: Moist, nutrient-rich forests of floodplains and slopes, calcareous

 

VIDEO Created by Elisabeth Meyer for "Vegetables, Herbs, Fruits, and Nuts" a plant identification course offered in partnership with Longwood Gardens.   

Profile Video:
See this plant in the following landscape:
Cultivars / Varieties:
'Black Gem', 'Kwik-Krop'
Tags:
#deciduous#shade tree#native tree#moth caterpillar host#edible nuts#nuts#NC native#single trunk#nighttime garden#native garden#Braham Arboretum#larval host plant#allelopathic#food source fall#food source herbage#coastal UPL#food source hard mast fruit#mammals#butterfly friendly#Piedmont Mountains FACU#ebh#ebh-fn#native edible#problem for dogs#juglone#problem for horses#non-toxic for cats#Audubon#hickory horndevil moth#vhfn#vhfn-n#landscape plant sleuths course#wildlife friendly#woodland
 
Cultivars / Varieties:
'Black Gem', 'Kwik-Krop'
Tags:
#deciduous#shade tree#native tree#moth caterpillar host#edible nuts#nuts#NC native#single trunk#nighttime garden#native garden#Braham Arboretum#larval host plant#allelopathic#food source fall#food source herbage#coastal UPL#food source hard mast fruit#mammals#butterfly friendly#Piedmont Mountains FACU#ebh#ebh-fn#native edible#problem for dogs#juglone#problem for horses#non-toxic for cats#Audubon#hickory horndevil moth#vhfn#vhfn-n#landscape plant sleuths course#wildlife friendly#woodland
  • Attributes:
    Genus:
    Juglans
    Species:
    nigra
    Family:
    Juglandaceae
    Uses (Ethnobotany):
    Yellow dye made from fruit husks, seed is used in candy-making, cleaning abrasives, and explosives. Heartwood is of superior quality and value; heavy, hard, and strong with very little warping as it dries. Highly prized for furniture, cabinets, etc.
    Life Cycle:
    Woody
    Recommended Propagation Strategy:
    Seed
    Country Or Region Of Origin:
    Eastern United States, west to Texas, and South Eastern Canada
    Distribution:
    Northeast Canada west to North Dakota, Southwest to Utah South to Texas East to Florida.
    Wildlife Value:
    This plant supports Hickory Horndevil (Citheronia regalis) larvae which have one brood and appear from May to mid-September. Adult Hickory Horndevil moths do not feed. Also a Larval host for Banded Hairstreak butterflies and Luna moth. Meat of the nut is sweet and edible and a favorite food for squirrels.
    Particularly Resistant To (Insects/Diseases/Other Problems):
    Heat, drought, and soil compaction tolerant.
    Edibility:
    Nut is sweet and edible. An edible oil is obtained from the seed, but it tends to go rancid quickly. Used as a seasoning in bread, squash and other foods.
    Dimensions:
    Height: 50 ft. 0 in. - 75 ft. 0 in.
    Width: 50 ft. 0 in. - 70 ft. 0 in.
  • Whole Plant Traits:
    Plant Type:
    Edible
    Native Plant
    Tree
    Woody Plant Leaf Characteristics:
    Deciduous
    Habit/Form:
    Open
    Oval
    Rounded
    Growth Rate:
    Rapid
    Maintenance:
    Medium
    Texture:
    Coarse
  • Cultural Conditions:
    Light:
    Full sun (6 or more hours of direct sunlight a day)
    Partial Shade (Direct sunlight only part of the day, 2-6 hours)
    Soil Texture:
    Clay
    Loam (Silt)
    Sand
    Soil pH:
    Acid (<6.0)
    Neutral (6.0-8.0)
    Soil Drainage:
    Good Drainage
    Moist
    Occasionally Dry
    Occasionally Wet
    Very Dry
    NC Region:
    Coastal
    Mountains
    Piedmont
    USDA Plant Hardiness Zone:
    4a, 4b, 5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b
  • Fruit:
    Fruit Color:
    Black
    Brown/Copper
    Gold/Yellow
    Green
    Fruit Value To Gardener:
    Edible
    Fragrant
    Display/Harvest Time:
    Fall
    Fruit Type:
    Nut
    Fruit Length:
    1-3 inches
    Fruit Width:
    1-3 inches
    Fruit Description:
    Brown to black nut inside a fleshy, non-splitting, yellow-green husk that heavily stains skin and clothing. Displays in October. Nut inside is edible. Fruit attached singly or in pairs, globular, with pointed apex.
  • Flowers:
    Flower Color:
    Gold/Yellow
    Green
    Flower Inflorescence:
    Catkin
    Insignificant
    Flower Bloom Time:
    Spring
    Flower Size:
    3-6 inches
    Flower Description:
    Single-stemmed catkins 2 ½ to 5 ½ in long, short spiked near twig and yellow-green in color, appearing from April to May. Monoecious.
  • Leaves:
    Woody Plant Leaf Characteristics:
    Deciduous
    Leaf Color:
    Green
    Leaf Value To Gardener:
    Fragrant
    Showy
    Deciduous Leaf Fall Color:
    Gold/Yellow
    Insignificant
    Leaf Type:
    Compound (Pinnately , Bipinnately, Palmately)
    Leaf Arrangement:
    Alternate
    Leaf Shape:
    Lanceolate
    Ovate
    Leaf Margin:
    Lobed
    Serrate
    Hairs Present:
    No
    Leaf Length:
    > 6 inches
    Leaf Width:
    3-6 inches
    Leaf Description:
    Leaves emerge late and drop early; 12 to 24 inches long with 15 to 23 leaflets, ovate-lanceolate and finely serrate. 3-lobed leaf scar resembling a monkey face. Leaves drop sporadically during the season. More ovate, more leaflets, and less serrated margins than pecan. Leafing is in late spring with yellow-green leaves and fall color of bright clear yellow.
  • Bark:
    Bark Color:
    Black
    Dark Brown
    Surface/Attachment:
    Furrowed
    Ridges
    Bark Plate Shape:
    Diamond
    Bark Description:
    Brown ridged and furrowed with rough diamond pattern bark. Bark is thick.
  • Stem:
    Stem Color:
    Black
    Brown/Copper
    Stem Is Aromatic:
    No
    Stem Leaf Scar Shape:
    Encircles a bud
    Stem Lenticels:
    Conspicuous
    Pith (Split Longitudinally):
    Chambered
    Stem Description:
    V-shaped leaf scar with a bud nestled inside. The surface has raised lenticels and the pith of new branches is chambered with thin, buff-colored diaphrams defining the chambers.
  • Landscape:
    Landscape Location:
    Meadow
    Woodland
    Landscape Theme:
    Butterfly Garden
    Edible Garden
    Native Garden
    Nighttime Garden
    Design Feature:
    Shade Tree
    Attracts:
    Moths
    Small Mammals
    Resistance To Challenges:
    Drought
    Rabbits
    Problems:
    Allelopathic
    Problem for Dogs
    Problem for Horses
  • Poisonous to Humans:
    Poison Severity:
    Low
    Poison Symptoms:
    Dogs: moldy nuts/hulls can cause tremors and seizures, ingestion of shavings can cause incoordination; Horses: laminitis, colic.
    Poison Toxic Principle:
    Unknown
    Causes Contact Dermatitis:
    No