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Taiwan lily (Lilium formosanum)

Taiwan lily is a perennial bulb that can multiply rapidly and grow from seed to flower in as little as six months. It occurs in parts of New South Wales, including coastal regions and the Central Tablelands, and can be a persistent weed at infested sites.

Key facts

Type: Weed, herb.

Native to: Taiwan.

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

Other names: Formosan lily, tiger lily.

Best time to act: Look for and treat actively growing plants between flowering and fruiting, and revisit the site to check for regrowth and seedlings.

Identification

  • A perennial herb that can grow up to 2 m tall.
  • Its thin leaves are arranged alternately along the stem, are up to 15 cm long and 1 cm wide, and become smaller higher up the stem.
  • The large, fragrant, trumpet-shaped flowers are white and sometimes purplish on the outside; the petal tips curve backwards.
  • It produces cylindrical capsules up to 8 cm long and 1 cm wide.

Where it grows

In New South Wales it grows in coastal regions and the Central Tablelands, and is often found along roadsides.

Why it matters

  • It can multiply rapidly, making infestations difficult to manage.
  • Plants can grow from seed to flower in as little as six months, allowing seed production soon after establishment.
  • Where it establishes, it can compete with other vegetation and require ongoing site management.

How it spreads

  • It spreads by bulbs and by seed.
  • Avoid moving bulbs, seed capsules or contaminated soil from infested sites.

Control options

  • For physical control, remove the bulbs and as much of the underground material as practicable, and contain plant material so bulbs or seeds are not spread.
  • For larger infestations, use only herbicides registered for the situation and follow the product label and any applicable permit; spot spraying is described for actively growing plants between flowering and fruiting.
  • A cut-stump method is also described: prune shoots horizontally at the rhizome and apply an appropriate herbicide gel to the cut surface, following the label and permit.
  • Check treated areas for regrowth and new seedlings, and follow up as needed; contact a local council weeds officer for identification advice and local guidance.

Hygiene and washdown

  • Before leaving an infested site, remove soil and plant material from boots, tools, vehicles and machinery, and contain it at the site.
  • Do not transport contaminated soil or plant waste to clean areas.
  • 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: Declared pest (C1), prohibited. C1 Exclusion: to be kept out of WA, or out of the parts of WA where it is not established. Report any sighting to DPIRD. It must not be brought into WA (prohibited organism).
  • Tasmania: Not declared. Not a declared weed in Tasmania. Other laws may still apply.
  • Northern Territory: Not declared. Not on the NT A to Z weed list, and Weeds Australia does not list it as declared in the NT. Check the NT declared weeds list before moving or planting it.
  • 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
  • South Australia: Landscape South Australia Act 2019 (SA), administered by the regional landscape board

Sources