Honey locust

Native to North America (from Mexico to Canada), honey locust is a large, spiny, rapidly growing tree. Honey locust has been promoted and planted in Australia as a fodder tree and garden ornamental.

Honey locust forms dense, spiny thickets that can out-compete native vegetation, provide a haven for pests, and injure stock and humans. It is a major threat to the environment and sustainable pasture production.

You must manage the impacts of Honey locust on your land.

You must not give away, sell or release Honey locust into the environment.

Scientific name

Gleditsia triacanthos incl. cultivars and varieties

Other names

  • Honey locust tree, McConnel's curse, bean tree, sweet locust, soetpeul, thorntree honey locust, common honey locust, honey shuck, sweet bean locust

Similar species

  • Ornamental honey locust

Description

  • Deciduous, leguminous tree up to 20m tall.
  • Leaves are prolific, green, up to 20cm long, with about 12 opposite paired leaflets.
  • Trunk and limbs of wild trees bear very large crucifix-like spines, up to 15cm long.
  • Flower stalks are creamy, yellow, 10cm long.
  • Pods are brown, 20–30cm long, containing 15–30 seeds surrounded by sweet pulp.
  • Seeds are flattened, brown, about 10mm long.
  • Grafted ornamental, thornless varieties produce thorns at later date or throw thorny progeny.

Habitat

  • Grows in most soil types, especially on alluvial flood plains along river systems.

Distribution

  • Visit Weeds Australia and click on the distribution tab to access the distribution map.

Life cycle

  • Flowering starts at 3–5 years and occurs in October–November.
  • Seeds prolifically every 1–2 years.
  • Seeds can remain viable for at least 20 years.
  • Seeds usually produced annually, with large crops occurring every 2 years.

Affected animals

  • Livestock
  • Native animals
  • Humans

Impacts

Environmental

  • Out-competes and replaces native vegetation.
  • Provides haven for introduced pests such as foxes, cats and rabbits.

Economic

  • Sharp spines can injure livestock and damage equipment and vehicles.
  • Forms dense thickets, particularly along waterways, preventing stock access to water.

Social

  • Sharp spines can injure humans and wildlife.

How it is spread

  • Seed spread by grazing stock, floodwaters, and ornamental plantings.

Control

Mechanical control

  • Bulldozing breaks plants at or above ground level. Once broken, honey locust will vigorously produce regrowth from broken bases and roots. Follow up with some other form of control such as cultivation or herbicide to prevent regrowth after bulldozing.
  • On arable land, bulldozing followed by deep ploughing can control dense infestations, but only if followed by regular cropping and/or spot spraying of regrowth. If cultivation is abandoned, reseeding from nearby trees can be a problem.

Herbicide control

  • Herbicides are effective.

Read the honey locust fact sheet (PDF, 5.4MB) for herbicide control and application rates.

Biological control

  • No known biological control agents.

Legal requirements

All species of Gleditsia are prohibited invasive plants except for Gleditsia tricanthos, which are category 3 restricted invasive plants under the Biosecurity Act 2014.

Prohibited

  • All species of Gleditsia are prohibited invasive plants under the Biosecurity Act 2014.
  • You must not keep, move, give away, sell or release into the environment. Penalties may apply.
  • You must not take any action reasonably likely to exacerbate the biosecurity threat posed by Gleditsia spp.
  • You must take any action that is reasonably likely to minimise the biosecurity threat posed by Gleditsia spp.
  • The Act requires that all sightings to be reported to Biosecurity Queensland within 24 hours.

Restricted

  • Honey locust is a category 3 restricted invasive plant under the Biosecurity Act 2014.
  • It must not be given away, sold, or released into the environment. Penalties may apply.
  • You must take all reasonable and practical measures to minimise the biosecurity risks associated with dealing with honey locust under your control. This is called a general biosecurity obligation (GBO).
  • At a local level, each local government agency must have a biosecurity plan that covers invasive plants in its area. This plan may include actions to be taken on honey locust. Some of these actions may be required under local laws. Contact your local council for more information.

Further information