Black Locust

Robinia pseudoacacia

1. Black Locust is a medium-sized tree that can reach heights of 30 to 70 feet (9 to 21 meters) with a spread of 20 to 40 feet (6 to 12 meters). It has a distinctive upright and irregularly shaped crown. The leaves are pinnately compound, with 7 to 21 leaflets that are oval-shaped and smooth-edged. 

2. Growing Conditions: Black Locust is known for its adaptability to various soil types, including poor, rocky, and acidic soils. It prefers full sun but can tolerate some shade. It is a hardy tree that can withstand harsh conditions, including drought and pollution. It is suitable for USDA hardiness zones 4 to 8.

3. Maintenance: Once established, Black Locust is relatively low-maintenance. It is drought-tolerant and requires minimal watering, except during prolonged dry periods. Pruning is generally not necessary, but you can remove any dead or damaged branches as needed. 

MAINTENANCE NEEDS:  Medium maintenance.  Do not prune in spring. It is susceptible to locust borer, which is often fatal, and locust leaf miner.  Potential diseases include canker, powdery mildew, leaf spots, wood rots and verticillium wilt.  Potential pests  include caterpillars, weevils, scale and whiteflies.  Promptly remove root suckers unless naturalization is wanted.

LANDSCAPE USES: Group Plantings or Specimen Tree,  Naturalized Areas,  Woodland Gardens, and  Shade Tree

COMPANION PLANTS: Arborvitae, Mock Orange, Blanket Flower

IMAGES:  Famartin,  2020-05-25 17 38 33 A Black Locust blooming along West Virginia State Route 42 (Lunice Creek Highway) just north of Pleasant View Drive in Maysville, Grant County, West Virginia,  CC BY-SA 4.0, (2)   JoJan,  Robinia pseudacacia11,  CC BY-SA 3.0, (3)  Famartin,  2020-10-22 12 03 49 A Black Locust turning yellow in autumn along a walking path in the Franklin Farm section of Oak Hill, Fairfax County, Virginia, CC BY-SA 4.0, (4) Photo by  So_P,  Robinier faux acacia, (5)  Andrew Butko,  Ab plant 1994, CC BY-SA 3.0, (6)  Kora27,  Rhododendronpark in Wachwitz; Sachsen ..2H1A5211WI, CC BY-SA 4.0

*As plants have ranges in appearance they may not appear as the images shown.