Biosecurity Spotters logo

Prairie ground cherry (Physalis hederifolia)

Prairie ground cherry forms dense infestations in NSW crops and grazing land. It competes with crops and pasture species, reducing yields and productivity, and can contaminate grain and hay.

Key facts

Type: Weed, herb.

Native to: North America.

Established in: NSW, ACT, VIC, SA.

Other names: sticky cape gooseberry.

Best time to act: Look for seedlings after rainfall and treat actively growing plants before flowering.

Identification

  • It is an erect, perennial herb that usually grows up to 30 cm tall, with sparsely hairy stems and rhizomes.
  • Its light green leaves are narrow and oval, up to 5 cm long and 3 cm wide, and are usually toothed along the edges.
  • Its pale yellow, bell-shaped flowers are 2–3 cm across and often have olive-yellow blotches near the base.
  • The fruit is a round, orange, sticky berry inside a papery, dull yellow-green case that dries pale brown or straw-coloured.
  • Its roots are deep, often extending more than 1 m, and horizontal roots can produce new growth.
  • Look-alike: Perennial ground cherry (Physalis longifolia) looks very similar, but has olive-green blotches in the centre of its flowers and grows up to 50 cm tall.

Where it grows

In NSW it occurs mostly in the Murray region, with infestations also recorded in the Central West, Riverina and Western regions, in cropping land, pastures and along roadsides and railways.

Why it matters

  • Dense infestations compete with crops, especially summer crops, reducing yields.
  • They outcompete pasture species and reduce productivity.
  • The plant can contaminate grain and hay.
  • All Physalis species are potentially poisonous because they contain solanine, although livestock rarely eat the foliage and sheep eat the fruit with no apparent harm.

How it spreads

  • Plants can produce up to 4,500 seeds per year, and seeds can persist for up to 20 years when buried in an intact dry berry pod.
  • Seeds spread in fruit eaten by livestock, birds and other animals, and can also move by wind or water while still in the capsule, on cultivation equipment, and in contaminated hay.
  • Root pieces as small as 1.5 cm can regrow and spread on cultivation equipment or in contaminated hay.

Control options

  • Where possible, control plants before they flower to limit seed production; spray actively growing plants before flowering and cover all foliage with the herbicide mixture.
  • Small seedlings can be pulled or dug out after rainfall when the soil is soft; removing large plants is difficult because their roots are very deep.
  • Dense summer-growing pasture species and irrigated crops or pastures can outcompete the weed.
  • Avoid allowing livestock access to areas with fruiting plants, and use registered herbicides according to their labels and any permit conditions.

Hygiene and washdown

  • Avoid driving or taking machinery through infestations with fruiting plants; if unavoidable, clean vehicles and machinery before moving to an uninfested area.
  • Request a fodder vendor declaration to help limit the import of contaminated hay or fodder.
  • 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: Regional priority in 2 of 11 regions. Regional priority weed in Murray, Riverina. The general biosecurity duty applies: anyone dealing with it must prevent, eliminate or minimise the risk it poses.
  • Victoria: Regionally prohibited / regionally controlled / restricted weed (varies by region). Where it is regionally prohibited, landowners must take all reasonable steps to eradicate it on their land. Where it is regionally controlled, landowners must take all reasonable steps to prevent its growth and spread on their land. Where it is a restricted weed, trade in it (including the plant, its seed or contaminated material) is prohibited.
  • South Australia: Not declared. Not declared under the Landscape South Australia Act 2019. Other laws may still apply.
  • Western Australia: Not listed. Not found in the Western Australian Organism List. Check with DPIRD before moving or keeping it.
  • 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.

  • 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