Biosecurity Spotters logo

Sand oats (Avena strigosa)

Sand oats is an introduced annual grass that occasionally escapes cultivation in Australia, with records from New South Wales, Victoria, Tasmania and Western Australia. Where it grows as a weed, it can compete with crops and pasture plants, so land managers should identify it and prevent seed production and spread.

Key facts

Type: Weed, grass.

Native to: Europe.

Established in: NSW, VIC, TAS, WA.

Other names: Bristle oat, Black oat.

Best time to act: Look for plants during spring flowering and treat them before seed matures and is shed.

Identification

  • A glaucous annual grass, usually growing to about 1.2 m tall.
  • The leaf blades are 3–12 mm wide and rough to the touch; the ligule is usually blunt and 2–5 mm long.
  • Its loose, sometimes contracted panicle can reach 25 cm long, or 35 cm in some plants.
  • Spikelets are 2–2.5 cm long, excluding the awns, and contain two or three florets.
  • The narrow lemmas have distinct bristle-like tips and a usually 2–3 cm awn that may be nearly straight or bent and twisted.
  • Look-alike: It can be confused with other wild oats, including other Avena species; check mature spikelets and the lemma bristles and awns for identification.

Where it grows

In Australia it is an occasional escape from cultivation, and may be encountered in cultivated or disturbed ground.

Why it matters

  • As a weed, it can compete with crops and pasture plants for light, water and nutrients.
  • Its presence in cropped areas can make harvest and crop-seed handling more difficult if its seed is mixed with the crop.
  • Escapes from cultivation can establish unwanted plants beyond the area where it was sown.

How it spreads

  • Seeds can be moved in contaminated crop seed or fodder.
  • Seeds and seed-bearing material can be carried between sites on machinery, vehicles, equipment or soil.
  • Allowing plants to set seed increases the chance of further spread.

Control options

  • For small infestations, pull or dig plants before seed matures, and contain seed-bearing material so it cannot spread.
  • Where suitable, use only herbicides registered for the target site and follow the product label and local advice.
  • Prevent seed set by treating plants in time, and revisit the site to find and control regrowth or later seedlings.
  • Check with the relevant state or territory biosecurity agency for local advice and reporting requirements.

Hygiene and washdown

  • Clean soil and plant material from vehicles, machinery, boots and equipment before leaving an infested site.
  • Use clean seed and fodder, and avoid moving contaminated soil or seed-bearing material 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: 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: 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.

  • New South Wales: Biosecurity Act 2015 (NSW), administered by NSW Department of Primary Industries and Regional Development
  • Victoria: Catchment and Land Protection Act 1994 (Vic), administered by Agriculture Victoria
  • Tasmania: Biosecurity Act 2019 (Tas), administered by Biosecurity Tasmania
  • Western Australia: Biosecurity and Agriculture Management Act 2007 (WA), administered by the WA Department of Primary Industries and Regional Development

Sources