SelecTree: Tree Detail
BLACK LOCUST
Robinia pseudoacacia
Photo Locations: Stanford University - Palo Alto, CA, Central Park - New York City, NY, Hoyt Arboretum - Portland, OR and Los Gatos, CA
General Notes
Tolerates smog. Seeds, leaves and bark are poisonous. Has become established in natural areas (undisturbed, undeveloped environments) in California.
This plant is classified as invasive by the California Invasive Plant Council (Cal-IPC). Its rating is limited.
Has fragrant Flower.
Has thorns.
Native to Eastern and Central United States.
A Robinia pseudoacacia in Tulare is registered as a California Big Tree. It measures 68 feet high, with a trunk circumference of 156 inches and a crown spread of 62 feet.
Family: Fabaceae
Tree Characteristics
Erect or Spreading and requires ample growing space.
Rounded Shape.
Has Deciduous foliage.
Height: 40 - 70 feet.
Width: 25 - 35 feet.
Growth Rate: 36 Inches per Year.
Longevity 50 to 150 years.
Leaves Pinnately Compound Odd with Elliptic to Ovate Leaflets, Green, Golden or Yellow or Orange, Deciduous.
Flowers Showy. Fragrant White. Flowers in Spring or Summer. Has perfect flowers (male and female parts in each flower).
Brown Legume, Very Large (Over 3.00 inches), fruiting in Fall Wildlife use it.
Bark Dark Brown or Red Brown, Furrowed or Ridged.
Shading Capacity Rated as Moderately Low in Leaf.
Shading Capacity Rated as Low out of Leaf.
Litter Issue is Dry Fruit and Twigs.
Tree Site Conditions & Constraints
Sunset Zones 1 - 24.
USDA Hardiness Zones 4 - 8.
Exposure Full Sun to Partial Shade.
Wet to Dry Soil.
Clay, Loam or Sand Texture.
Highly Acidic to Highly Alkaline Soil pH.
Salinity Tolerance is Moderate Inland.
Seaside Tolerance is Good in Mild Zone.
Pests & Disease Information
Susceptible to Aphids and Beetle Borers, Fusarium, Armillaria, Phytophthora, Root Rot and Verticillium.
Health, Safety & Environmental Concerns
Branch Strength Rated as Medium Weak to Medium
Root Damage Potential Rated as High.
Allergy and Poisonous Health Hazard.
Biogenic Emissions considered High.
Fire Resistance is Favorable.
Desirable Wildlife Plant.
Attracts Birds.
Wildlife use Fruit.
Cite this tree:
SelecTree. "Robinia pseudoacacia Tree Record." 1995-2020. Aug 9, 2020.
< https://selectree.calpoly.edu/tree-detail/robinia-pseudoacacia >
This tree is not part of the SelecTree Nursery Connection. If you would like to see this tree listed, or know of a nursery that sells it, please contact us at ufei@calpoly.edu.