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Smooth cat's-ear (Hypochaeris glabra)

Introduced and naturalised in Western Australia, Smooth Cat's-ear is a common weed of lawns, horticultural areas, roadsides and bushland. It is toxic to horses and can be difficult to identify where it hybridises with Hypochaeris radicata.

Key facts

Type: Weed, herb.

Native to: Northern Africa, temperate and western Asia, and Europe.

Established in: QLD, NSW, ACT, VIC, TAS, SA, WA.

Other names: Flat Weed, Annual Flatweed, Smooth Cats-ear.

Best time to act: Look for it throughout the year, especially during its spring flowering flush, and treat regularly to prevent seeding.

Identification

  • It is a rosetted herb, usually annual but sometimes perennial or biennial, growing 0.08 to 0.5 m high.
  • Its leaves are smooth.
  • Flower heads grow up to 1.5 cm across and are yellow.
  • It can flower all year, with a flush mainly in spring.
  • Look-alike: Hypochaeris radicata is a similar exotic species; the two can hybridise, making identification difficult.

Where it grows

In Western Australia it occurs in lawns, horticultural areas, roadsides and bushland.

Why it matters

  • It is a common weed in lawns, horticultural areas, roadsides and bushland in Western Australia.
  • It is toxic to horses.
  • Mowing and grazing are ineffective and can promote its growth and flowering.
  • Fire usually kills plants, but heat stimulates germination of seed stored in the soil.

How it spreads

  • It reproduces by seed, and its fruit has a feathery pappus that aids wind dispersal.
  • Animals can disperse seed by adhesion and occasionally by ingestion.
  • Seed can remain germinable after passing through a horse's digestive system.

Control options

  • Hand-remove small infestations or isolated plants, making sure to remove the taproot.
  • For larger infestations, use registered herbicides and approved methods; apply regularly to prevent seeding.
  • Mowing and grazing are ineffective and often promote growth and flowering.
  • Read herbicide labels and safety data sheets, and check with the Australian Pesticides and Veterinary Medicines Authority about permit status for your situation.

Hygiene and washdown

  • Seed is dispersed by wind and animals, including by adhesion and occasionally ingestion.
  • 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: Not prohibited or restricted. Not listed as prohibited or restricted matter in Queensland. 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)
  • New South Wales: Biosecurity Act 2015 (NSW), administered by NSW Department of Primary Industries and Regional Development
  • Australian Capital Territory: Biosecurity Act 2023 (ACT), administered by ACT Biosecurity
  • Victoria: Catchment and Land Protection Act 1994 (Vic), administered by Agriculture Victoria
  • Tasmania: Biosecurity Act 2019 (Tas), administered by Biosecurity Tasmania
  • South Australia: Landscape South Australia Act 2019 (SA), administered by the regional landscape board
  • Western Australia: Biosecurity and Agriculture Management Act 2007 (WA), administered by the WA Department of Primary Industries and Regional Development

Sources