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The native species of honey-locust has large thorns on its stems and bark. For this reason, thornless honey-locust, also known as Gleditsia triacanthos f. inermis, is most commonly sold. For the sake of species diversity, it should only be planted after careful consideration of alternatives. The species may be difficult to find in nurseries. Most nurseries will carry the thornless form. 

This species is native to the Chicago region according to Swink and Wilhelm’s Plants of the Chicago Region, with updates made according to current research.

  • Family (English) Pea
  • Family (botanic) Fabaceae (formerly Leguminosae)
  • Planting site City parkway, Residential and parks, Restricted sites, Wide median
  • Tree or plant type Tree
  • Foliage Deciduous (seasonally loses leaves)
  • Native locale Chicago area, Illinois, North America
  • Size range Medium tree (25-40 feet), Large tree (more than 40 feet)
  • Mature height 30-70 feet
  • Mature width 30-70 feet
  • Light exposure Full sun (6 hrs direct light daily)
  • Hardiness zones Zone 3, Zone 4, Zone 5 (Northern Illinois), Zone 6 (City of Chicago), Zone 7, Zone 8, Zone 9
  • Soil preference Moist, well-drained soil
  • Tolerances Alkaline soil, Clay soil, Dry sites, Occasional flooding, Road salt, Wet sites
  • Season of interest early fall
  • Flower color and fragrance Inconspicuous
  • Shape or form Broad, Round
  • Growth rate Fast
  • Transplants well Yes
  • Planting considerations Commonly planted, Dangerous thorns
  • Wildlife Migrant birds
  • Has cultivars Yes

Native geographic location and habitat: 

C-Value: 2

Bark color and texture: 

The bark shows some red-brown in its early years and matures to a gray brown. The older bark is broken up into long strips that are raised along the sides. The bark and stems are heavily armored with long, sharp thorns.

Leaf or needle arrangement, size, shape, and texture: 

Alternate leaves may be pinnately compound or bipinnately compound with many small, oval leaflets. Its fall color is yellow.

Flower arrangement, shape, and size: 

The flowers are green and held in short clusters. They are not showy. Flowering occurs in late spring.

Fruit, cone, nut, and seed descriptions: 

The fruit are dark reddish-brown pods (legumes) and 8 or more inches long. At maturity, the pods may be curled or twisted.

Plant care: 

Honey-locust should be pruned in fall or winter.

List of pests, diseases, and tolerances: 

This species is heavily armed with thorns on the trunk and branches. A wide range of diseases and pests can affect this tree: honeylocust plant bug, spider mites, leaf spots and canker. It is tolerant of black walnut toxicity.

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