Robinia pseudoacacia: Uses (Ethnobotany)
The wood from this native is yellow, coarse grained, hard, strong, and naturally rot resistant and is often used to make fence posts and rails, mine timbers, and landscaping ties.
Plant Profile: Robinia pseudoacacia
Taxonomy: Robinia pseudoacaciaNames
Black Locust, Common Locust, False Acacia, Green Locust, Pea Flower Locust, White Locust, Yellow Locust
Phonetic Spelling:roh-BIN-ee-ah soo-doh-ah-KAY-see-ah
Genus:Robinia
Species:pseudoacacia
Family:Fabaceae
Robinia pseudoacacia, commonly known as Black Locust, is a deciduous tree that can reach heights of 50 to 70 feet and has a trunk diameter ranging from 3 to 4 feet. This species is indigenous to the mountainous regions of North Carolina but has been extensively cultivated across the state, adapting well to various soil and moisture conditions, with the exception of overly saturated soils. In other areas, Black Locust often grows in dense clusters on clay banks, in disturbed sites, or along fence lines. It is considered a relatively short-lived species, typically surviving around 90 years.
The tree features alternate, pinnately compound leaves that consist of 7 to 21 leaflets. Its bark is characterized by a gray or light brown color, thick and fibrous texture, and a heavily ridged, furrowed appearance. During spring and early summer, it produces fragrant, pea-like white flowers that hang in clusters up to 5 inches long. The fruit is a flattened legume measuring 2 to 4 inches, containing 4 to 8 reddish-brown seeds.
Black Locust thrives in various soil types and possesses the unique ability to fix nitrogen, making it useful for soil reclamation in abandoned areas. It is well-suited for challenging environments, transplants easily, and tends to reseed itself. The tree can also generate shoots from its roots. As a legume, it contributes to nitrogen fixation and shows moderate tolerance to salt. However, it is sometimes regarded as somewhat weedy, as its extensive underground root suckers can create maintenance challenges and disrupt nearby gardens. To manage its size, Black Locust can be pruned to shrub height by cutting it back to the ground every 2 to 3 years, although spring pruning should be avoided to prevent excessive sap loss. Due to its invasive nature, thorny branches, and brittle limbs that are prone to breaking in strong winds, this tree is generally not recommended for landscaping.
In terms of pests and diseases, Black Locust is vulnerable to locust borers, which can be fatal, and locust leaf miners, which cause foliage discoloration. Other insect threats include caterpillars, weevils, scale insects, and whiteflies. It may also suffer from various diseases such as cankers, powdery mildew, leaf spots, wood rots, and verticillium wilt. Additionally, small branches are likely to break off during storms, and some leaves may yellow and drop in drought conditions.
Robinia pseudoacacia Feature Summary
Robinia pseudoacacia Image Gallery
Tags
#thorns
#showy flowers
#deciduous
#invasive
#poisonous
#fragrant flowers
#white flowers
#wildlife plant
#showy
#native tree
#salt tolerant
#cover plant
#spring flowers
#wetlands
#food source
#fast growing
#low flammability
#NC native
#fire resistant
#pollinator plant
#Braham Arboretum
#poor soils tolerant
#larval host plant
#food source summer
#food source fall
#food source herbage
#food source nectar
#food source pollen
#coastal UPL
#bird friendly
#food source hard mast fruit
#mammals
#butterfly friendly
#Piedmont Mountains FACU
#problem for cats
#larval host tree
#pollinator garden
#problem for dogs
#bee friendly
#problem for children
#problem for horses
#audubon
#silver-spotted skipper butterfly
#clouded sulphur butterfly
#zarucco duskywing butterfly
Similar Plants
Robinia pseudoacacia is often confused with:
Robinia pseudoacacia Feature Summary
Attributes
The wood from this native is yellow, coarse grained, hard, strong, and naturally rot resistant and is often used to make fence posts and rails, mine timbers, and landscaping ties.
Eastern and central United States
Appalachian and Ozark mountain ranges, but now naturalized and found in all 48 states of the contiguous United States.
This is a larval host plant for several butterflies. Clouded Sulphur (Colias philodice) larvae appear from May to October in the north and from March to November in the south. There are 3 flights in the north and 4 to 5 flights in the south (but it rarely uses this plant as a host in North Carolina). Zarucco Duskywing (Erynnis zarucco) has three broods in the deep south from March-October, appearing as early as January in Florida. Silver-Spotted Skipper (Epargyreus clarus) appears from May-September with three-four broods in the deep south, two broods in the east, and one brood in the north and west. The buds and catkins are eaten by birds. It provides an excellent leaf cover for birds in wetland sites. Bees are attracted to its flowers and rabbits depend on the sprouts and seeds during the winter.
Fire in the landscape. Heat and drought tolerant.
All parts of the tree are considered toxic. The toxins are destroyed by heat.
Woody
Fragrance
Wildlife Food Source
low flammability
Fruit
The flowers are followed by smooth, flat, purple-brown,flat, seed pods (to 4 to 5 inches long) each bearing 4 to 8 kidney-shaped seeds. These display from July to November and the pods can persist on the tree through the winter.
Legume
Brown/Copper
Purple/Lavender
> 3 inches
Flowers
Fragrant wisteria-like white flowers in pendant racemes (to 8 inches long) bloom from April to June. They are pea-like and very fragrant.
White
Raceme
Fragrant
Showy
Spring
Summer
fused petals
Lipped
Leaves
The leaf of the Black locust is noted for its attractive alternate, compound leaves and pendant racemes of pea-like flowers. It has pinnate dark blue-green leaves, 8 to 14 inches long, with each leaf having up to 23 lance-shaped to ovate leaflets. Leaves turn uneventful yellow in fall.
Deciduous
Green
Blue
Brown/Copper
Gold/Yellow
Compound (Pinnately , Bipinnately, Palmately)
Alternate
Ovate
Entire
> 6 inches
> 6 inches
Bark
Deeply furrowed and scaley.
Dark Brown
Light Brown
Black
Scaly
Ridges
Furrowed
Stem
Its branches are usually armed with short paired spines (to 1.25 inches long) adjacent to each leaf scar.
Round
Smooth (glabrous)
Poisonous to Humans
If ingested, it may cause death in humans and livestock and pets. Depression, weakness, dilated pupils, vomiting, bloody diarrhea, weak pulse, coldness of arms and legs, paleness, and shock.
Robin, a phytotoxin; robitin, a glycoside; robinine, an alkaloid.
High
Seeds
Leaves
Bark
Whole Plant Traits
Tree
Native Plant
Poisonous
Deciduous
Rounded
Erect
Oval
Rapid
Medium
Medium
Spines
Thorns
Cultural Conditions
Full sun (6 or more hours of direct sunlight a day)
Partial Shade (Direct sunlight only part of the day, 2-6 hours)
Acid (<6.0)
Alkaline (>8.0)
Neutral (6.0-8.0)
Good Drainage
Moist
Occasionally Dry
Coastal
Mountains
Piedmont
4a
4b
5b
5a
6a
6b
7a
7b
8b
8a
3a
3b
9a
9b
Clay
High Organic Matter
Loam (Silt)
Sand
Landscape
Butterfly Garden
Pollinator Garden
Native Garden
Flowering Tree
Drought
Pollution
Salt
Dry Soil
Black Walnut
Fire
Poor Soil
Recreational Play Area
Naturalized Area
Butterflies
Pollinators
Songbirds
Bees
Small Mammals
Hummingbirds
Poisonous to Humans
Problem for Cats
Problem for Dogs
Problem for Horses
Problem for Children
Robinia pseudoacacia Image Gallery
Robinia pseudoacacia Attributes
Robinia pseudoacacia: Country Or Region Of Origin
Eastern and central United States
Robinia pseudoacacia: Distribution
Appalachian and Ozark mountain ranges, but now naturalized and found in all 48 states of the contiguous United States.
Robinia pseudoacacia: Wildlife Value
This is a larval host plant for several butterflies. Clouded Sulphur (Colias philodice) larvae appear from May to October in the north and from March to November in the south. There are 3 flights in the north and 4 to 5 flights in the south (but it rarely uses this plant as a host in North Carolina). Zarucco Duskywing (Erynnis zarucco) has three broods in the deep south from March-October, appearing as early as January in Florida. Silver-Spotted Skipper (Epargyreus clarus) appears from May-September with three-four broods in the deep south, two broods in the east, and one brood in the north and west. The buds and catkins are eaten by birds. It provides an excellent leaf cover for birds in wetland sites. Bees are attracted to its flowers and rabbits depend on the sprouts and seeds during the winter.
Robinia pseudoacacia: Particularly Resistant To (Insects/Diseases/Other Problems)
Fire in the landscape. Heat and drought tolerant.
Robinia pseudoacacia: Edibility
All parts of the tree are considered toxic. The toxins are destroyed by heat.
Robinia pseudoacacia: Life Cycle
Annual
Biennial
Bulb
Perennial
Woody
Robinia pseudoacacia: Recommended Propagation Strategy
Division
Grafting
Layering
Leaf Cutting
Root Cutting
Seed
Stem Cutting
Robinia pseudoacacia: Play Value
Attractive Flowers
Attracts Pollinators
Buffer
Colorful
Defines Paths
Easy to Grow
Edible fruit
Fragrance
Pieces Used in Games
Screening
Shade
Sound
Textural
Wildlife Cover/Habitat
Wildlife Food Source
Wildlife Larval Host
Wildlife Nesting
Wind Break
Wind Shimmer
Robinia pseudoacacia: Fire Risk Rating
extreme flammability
high flammability
low flammability
medium flammability
Robinia pseudoacacia Fruit
Robinia pseudoacacia: Fruit Description
The flowers are followed by smooth, flat, purple-brown,flat, seed pods (to 4 to 5 inches long) each bearing 4 to 8 kidney-shaped seeds. These display from July to November and the pods can persist on the tree through the winter.
Robinia pseudoacacia: Fruit Type
Achene
Aggregate
Berry
Capsule
Caryopsis
Drupe
Follicle
Legume
Nut
Pome
Samara
Schizocarp
Siliqua
Robinia pseudoacacia: Fruit Color
Brown/Copper
Purple/Lavender
Robinia pseudoacacia: Display/Harvest Time
Fall
Spring
Summer
Winter
Robinia pseudoacacia: Fruit Length
< 1 inch
1-3 inches
> 3 inches
Robinia pseudoacacia Flowers
Robinia pseudoacacia: Flower Description
Fragrant wisteria-like white flowers in pendant racemes (to 8 inches long) bloom from April to June. They are pea-like and very fragrant.
Robinia pseudoacacia: Flower Color
White
Robinia pseudoacacia: Flower Inflorescence
Catkin
Corymb
Cyme
Head
Insignificant
Panicle
Raceme
Solitary
Spadix
Spike
Umbel
Robinia pseudoacacia: Flower Value To Gardener
Edible
Fragrant
Good Cut
Good Dried
Long Bloom Season
Long-lasting
Showy
Robinia pseudoacacia: Flower Bloom Time
Winter
Spring
Summer
Fall
Robinia pseudoacacia: Flower Petals
2-3 rays/petals
4-5 petals/rays
6 petals/rays
7 - 20 petals/rays
asymmetrical petals
Bracts
Colored Sepals
fused petals
more than 20 petals/rays
Tepals
Robinia pseudoacacia: Flower Shape
Bell
Cross
Crown
Cup
Dome
Funnel
Irregular
Lipped
Radial
Saucer
Star
Trumpet
Tubular
Urn
Wheel
Robinia pseudoacacia Leaves
Robinia pseudoacacia: Leaf Description
The leaf of the Black locust is noted for its attractive alternate, compound leaves and pendant racemes of pea-like flowers. It has pinnate dark blue-green leaves, 8 to 14 inches long, with each leaf having up to 23 lance-shaped to ovate leaflets. Leaves turn uneventful yellow in fall.
Robinia pseudoacacia: Woody Plant Leaf Characteristics
Broadleaf Evergreen
Deciduous
Needled Evergreen
Semi-evergreen
Robinia pseudoacacia: Leaf Color
Blue
Brown/Copper
Green
Robinia pseudoacacia: Deciduous Leaf Fall Color
Gold/Yellow
Robinia pseudoacacia: Leaf Type
Compound (Pinnately , Bipinnately, Palmately)
Fronds
Needles
Sheath
Simple
Robinia pseudoacacia: Leaf Arrangement
Alternate
Opposite
Other/more complex
Rosulate
Whorled
Robinia pseudoacacia: Leaf Shape
Acicular
Auriculate
Cordate
Cuneate
Deltoid
Elliptical
Filiform
Lanceolate
Linear
Oblanceolate
Oblong
Obovate
Obtuse
Orbicular
Ovate
Palmasect
Palmatifid
Peltate
Pinnatifid
Pinnatisect
Reniform
Rhomboidal
Spatulate
Subcordate
Subulate
Robinia pseudoacacia: Leaf Margin
Crenate
Crenulate
Dentate
Denticulate
Doubly Crenate
Doubly Dentate
Doubly Serrate
Entire
Lobed
Serrate
Sinuate
Undulate
Robinia pseudoacacia: Hairs Present
No
Yes
Robinia pseudoacacia: Leaf Length
< 1 inch
1-3 inches
3-6 inches
> 6 inches
Robinia pseudoacacia: Leaf Value To Gardener
Edible
Fragrant
Good Cut
Good Dried
Long-lasting
Showy
Robinia pseudoacacia: Leaf Width
< 1 inch
1-3 inches
3-6 inches
> 6 inches
Robinia pseudoacacia Bark
Robinia pseudoacacia: Bark Description
Deeply furrowed and scaley.
Robinia pseudoacacia: Bark Color
Black
Dark Brown
Light Brown
Robinia pseudoacacia: Surface/Attachment
Bumpy
Exfoliating
Fissured
Furrowed
Lenticels
Papery
Patchy
Peeling
Ridges
Scaly
Shaggy
Shiny
Shredding
Smooth
Spongy
Robinia pseudoacacia Stem
Robinia pseudoacacia: Stem Description
Its branches are usually armed with short paired spines (to 1.25 inches long) adjacent to each leaf scar.
Robinia pseudoacacia: Stem Is Aromatic
No
Yes
Robinia pseudoacacia: Stem Cross Section
Angular
Oval
Round
Square
Robinia pseudoacacia: Stem Surface
Corky Ridges
Covered with a powdery bloom (glaucous)
Dull
Hairy (pubescent)
Polished
Smooth (glabrous)
Robinia pseudoacacia Poisonous to Humans
Robinia pseudoacacia: Poison Symptoms
If ingested, it may cause death in humans and livestock and pets. Depression, weakness, dilated pupils, vomiting, bloody diarrhea, weak pulse, coldness of arms and legs, paleness, and shock.
Robinia pseudoacacia: Poison Toxic Principle
Robin, a phytotoxin; robitin, a glycoside; robinine, an alkaloid.
Robinia pseudoacacia: Poison Severity
High
Low
Medium
Robinia pseudoacacia: Causes Contact Dermatitis
No
Yes
Robinia pseudoacacia: Poison Part
Bark
Flowers
Fruits
Leaves
Roots
Sap/Juice
Seeds
Stems
Robinia pseudoacacia Whole Plant Traits
Robinia pseudoacacia: Plant Type
Annual
Bulb
Carnivorous
Edible
Epiphyte
Fern
Ground Cover
Herb
Herbaceous Perennial
Houseplant
Mushroom
Native Plant
Ornamental Grasses and Sedges
Perennial
Poisonous
Rose
Shrub
Succulent
Tree
Turfgrass
Vegetable
Vine
Water Plant
Weed
Wildflower
Robinia pseudoacacia: Woody Plant Leaf Characteristics
Broadleaf Evergreen
Deciduous
Needled Evergreen
Semi-evergreen
Robinia pseudoacacia: Habit/Form
Arching
Ascending
Broad
Cascading
Climbing
Clumping
Columnar
Conical
Creeping
Dense
Erect
Horizontal
Irregular
Mounding
Multi-stemmed
Multi-trunked
Open
Oval
Prostrate
Pyramidal
Rounded
Spreading
Vase
Weeping
Robinia pseudoacacia: Growth Rate
Slow
Medium
Rapid
Robinia pseudoacacia: Maintenance
Low
Medium
High
Robinia pseudoacacia: Texture
Fine
Medium
Coarse
Robinia pseudoacacia: Appendage
Prickles
Spines
Tendrils
Thorns
Robinia pseudoacacia Cultural Conditions
Robinia pseudoacacia: Light
Dappled Sunlight (Shade through upper canopy all day)
Deep shade (Less than 2 hours to no direct sunlight)
Full sun (6 or more hours of direct sunlight a day)
Partial Shade (Direct sunlight only part of the day, 2-6 hours)
Robinia pseudoacacia: Soil pH
Acid (<6.0)
Alkaline (>8.0)
Neutral (6.0-8.0)
Robinia pseudoacacia: Soil Drainage
Frequent Standing Water
Good Drainage
Moist
Occasional Flooding
Occasionally Dry
Occasionally Wet
Very Dry
Robinia pseudoacacia: NC Region
Coastal
Mountains
Piedmont
Robinia pseudoacacia: USDA Plant Hardiness Zone
3a
3b
4a
4b
5a
5b
6a
6b
7a
7b
8a
8b
9a
9b
Robinia pseudoacacia: Soil Texture
Clay
High Organic Matter
Loam (Silt)
Sand
Shallow Rocky
Robinia pseudoacacia Landscape
Robinia pseudoacacia: Landscape Theme
Asian Garden
Butterfly Garden
Children's Garden
Cottage Garden
Cutting Garden
Drought Tolerant Garden
Edible Garden
English Garden
Fairy Garden
Garden for the Blind
Native Garden
Nighttime Garden
Pollinator Garden
Rain Garden
Rock Garden
Shade Garden
Water Garden
Winter Garden
Robinia pseudoacacia: Design Feature
Accent
Barrier
Border
Flowering Tree
Foundation Planting
Hedge
Mass Planting
Screen/Privacy
Security
Shade Tree
Small groups
Small Tree
Specimen
Street Tree
Understory Tree
Robinia pseudoacacia: Resistance To Challenges
Black Walnut
Compaction
Deer
Diseases
Drought
Dry Soil
Erosion
Fire
Foot Traffic
Heat
Heavy Shade
Humidity
Insect Pests
Pollution
Poor Soil
Rabbits
Salt
Slugs
Squirrels
Storm damage
Urban Conditions
Voles
Wet Soil
Wind
Robinia pseudoacacia: Landscape Location
Coastal
Container
Hanging Baskets
Houseplants
Lawn
Meadow
Naturalized Area
Near Septic
Patio
Pond
Pool/Hardscape
Recreational Play Area
Riparian
Rock Wall
Slope/Bank
Small Space
Vertical Spaces
Walkways
Woodland
Robinia pseudoacacia: Attracts
Bats
Bees
Butterflies
Frogs
Hummingbirds
Moths
Pollinators
Predatory Insects
Reptiles
Small Mammals
Songbirds
Specialized Bees
Robinia pseudoacacia: Problems
Allelopathic
Contact Dermatitis
Frequent Disease Problems
Frequent Insect Problems
Invasive Species
Malodorous
Messy
Poisonous to Humans
Problem for Cats
Problem for Children
Problem for Dogs
Problem for Horses
Short-lived
Spines/Thorns
Weak Wood
Weedy
