Scientific Name: Robinia pseudoacacia
Common Name: black locust
Family Name: Fabaceae
Origin: Garden origin, U.S. - central, U.S. - northeast
Hardiness Zone: Zone 4: (-34 to -29 °C)
Plant Type: Tree - deciduous
Mature Size: 10 - 15m x 7 - 10m (height x width)
Habit: Arching, Open, Twiggy, Upright
Form: Columnar, Oval - vertical
Texture: Medium - fine
Landscape Uses: Erosion control, Reclamation, Shade tree, Specimen plant, Street (boulevard tree), Summer interest, Tall background, Woodland margin
Exposure: Full sun
Soil or Media: Rocky or gravelly or dry, Well-drained
Leaves: Compound, Alternate, Soft flexible, Pinnate venation, Glabrous, Odd-pinnate, Elliptic, Oblong, Ovate, Entire
Flowers: Raceme, White, Purple, May-Jun
Fruit: Legume, Purple, Brown, Black, Aug-Sep, (Persistent)
Key ID Features:
Leaves pinnately compound, most 10-30 cm long x 5-10cm wide, (3-)7-15(-23) leaflets, most oblong, 2-4cm long x 1-1.5cm wide, spiney stipules; golden-yellow (cv. Frisia) or bronze-green (cv. Purple Robe); florets 10-20 in pendant racemes, wisteria-like, 10-20cm long, florets pea-likem white or violet-purple, fragrant; legumes smooth, flat, 5-11cm long, purple-brown. Winter ID: bark longitudinally fissured on older trees or rarely smooth, twigs zig-zag, groved, pair of spiney stipules 0.5-2cm long at (some) nodes, buds tiny, terminal bud absent.