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Redwood (Acaciella glauca)

Redwood is an introduced shrub in Australia that can establish and spread from seed. Dense growth can crowd out native plants, so early identification and control help limit its spread.

Key facts

Type: Weed, shrub.

Native to: Venezuelan coast and the Caribbean.

Established in: QLD.

Other names: Acacia glauca, Mimosa glauca, Acaciella curassavica, Acacia curassavica.

Best time to act: Flowering and fruiting are recorded in January and February, so inspect then and treat plants before pods mature.

Identification

  • It is a glabrous shrub that can grow to about 6 m tall.
  • Its leaves are divided into 2–8 pairs of pinnae, each bearing 6–21 pairs of small, oblong leaflets.
  • Clusters of short racemes carry white flowers, which turn yellow when dried.
  • Its flat, straight pods are about 4.5–8 cm long and have conspicuous net-like veins.
  • Each pod contains about eight broadly ellipsoid seeds.
  • Look-alike: It may be confused with wattles (Acacia species); check for its many small leaflets and clusters of white flowers, as foliage alone may not be enough for reliable identification.

Where it grows

In Australia, look for it in warm tropical or subtropical sites, particularly disturbed ground and roadsides where it has become established.

Why it matters

  • It can form dense stands that compete with native plants for space and light.
  • Its spread can alter the composition of vegetation in invaded areas.
  • As an introduced shrub, it can become an ongoing control problem where plants establish and produce seed.

How it spreads

  • It reproduces by seed contained in its pods.
  • Pods or seeds can be carried with soil, machinery, garden waste or other moved material.

Control options

  • Remove small plants by hand where practical, taking care to remove the root system and avoid disturbing the site unnecessarily.
  • For larger plants, use an approved method such as cut-stump treatment with a herbicide currently registered or permitted for the species and site; follow the product label and local requirements.
  • Control plants before they produce mature pods, and collect and dispose of pod-bearing material so it cannot spread.
  • Revisit treated sites to check for regrowth and new seedlings; seek advice from the relevant state or territory biosecurity agency about reporting or local requirements.

Hygiene and washdown

  • Clean pods, seeds and soil from vehicles, machinery, boots and equipment before leaving an infested site.
  • Avoid moving contaminated soil or plant waste, and dispose of collected pods securely.
  • Inspect and clean vehicles, plant and footwear before leaving an infested area, paying attention to tyres, radiators, belly plates, tracks and floor mats.
  • Wash down at a designated bay where runoff is contained and can be monitored for seedlings.
  • Record each washdown so the client has evidence of clean entry and exit.

Classification by state

  • Australia (national): No national listing. Managed under state and territory law.
  • Queensland: Restricted matter, categories 2, 3, 4, 5. Report it to Biosecurity Queensland within 24 hours; do not give it away, sell or release it into the environment; do not move it; do not keep it. Everyone must also take all reasonable and practical steps to minimise its risks (the general biosecurity obligation).
  • New South Wales: Not a priority weed. Not a state or regional priority weed in NSW. The general biosecurity duty applies: anyone dealing with it must prevent, eliminate or minimise the risk it poses.
  • Victoria: Not declared. Not declared under the Catchment and Land Protection Act 1994. Other Victorian laws may still apply.
  • South Australia: Not declared. Not declared under the Landscape South Australia Act 2019. Other laws may still apply.
  • Western Australia: Permitted, not declared. Listed as a permitted organism in WA, so it can be brought in, but it is not a declared pest.
  • Tasmania: Not declared. Not a declared weed in Tasmania. Other laws may still apply.
  • Northern Territory: Check NT list. There is no NT weed profile for it. Check the NT declared weeds list for its current status.
  • Australian Capital Territory: Not declared. Not declared under the Biosecurity Act 2023 (ACT). A general biosecurity duty still applies.

Legal obligations

Every state and territory places a duty on landholders and people working on land to prevent the spread of invasive species, such as the general biosecurity obligation in Queensland and the general biosecurity duty in New South Wales. Declarations and control requirements differ between states and local government areas, so check the current official list before work starts.

  • Queensland: Biosecurity Act 2014 (Qld), administered by Biosecurity Queensland (13 25 23)

Sources