Parthenium - our greatest threat

Keep New South Wales parthenium-free

Parthenium is the greatest weed threat to New South Wales. It spreads rapidly. Contact with the plant or pollen can cause serious allergic reactions in people. It is dangerous to grazing animals, and reduces crop and land values. Endemic to an area of central Queensland covering 18 million hectares.

New South Wales has made keeping this weed out a top priority. Although harvesters are high-risk, outbreaks can occur from various sources including any machinery or vehicles that have been in parthenium weed areas of Queensland. The emphasis on keeping parthenium weed out of New South Wales rests with you, the owners and operators of cross-border machinery. Therefore the operators of all machinery, not just harvesters, have a duty of care to prevent their machines from spreading parthenium weed.

Clean your equipment first

Clean your machine before it leaves the farm. This minimises potential weed spread and promotes your image as a professional operator.

Parthenium seed is very small, so thoroughly clean your machine with a high volume air compressor. Use water jets only for mud and other contaminants that will not yield to air treatment.

Do not rely solely on cross-border inspections to test your machine's weed-free status — it should be cleaned before it gets anywhere near the border. Having your machine rejected at the border usually means many valuable hours lost because the machine has to be returned to the relevant border cleandown facility.

At the border, you will also be required to sign a declaration that your machine has been cleaned according to the regulation. Signing a false declaration is an offence.

Give farm-owners a good look

On arrival at a new job, offering the property owner an inspection of your harvester helps to assure your client that you are a professional and that you have taken all reasonable measures to ensure your machine is weed-free. It will also lessen the chance of a weed outbreak being wrongly attributed to your machinery.

If your machine has previously harvested on a property that was infested by parthenium weed, the property owner should be informed. Not disclosing this could increase your liability if parthenium weed did establish on that property. If your machine has however never been in a parthenium weed area, a log book or other evidence of this will reassure the property owner.

NOTE: The cleaning procedure described in this brochure — and required under the Biosecurity Regulation 2017 — reduces the immediate risk of spreading parthenium weed. It does not totally eliminate that risk since parthenium weed seed can remain trapped in inaccessible parts of the harvester. Any maintenance or repairs to your harvester that require the loosening of mechanical or structural components can dislodge parthenium weed seed. For any repairs then, remove the harvester from the crop and try to take the machine to an area that does not favour seedling establishment and that can be frequently inspected by the property owner. A gravelled area near the farm sheds is ideal. Always tell the property owner of this location and advise them to inspect the area subsequently.

Parthenium weed areas in Queensland

60 million hectares of Queensland are affected by parthenium weed. Parthenium weed infestations in Queensland are most likely to occur in the shires of Central Highlands, Izaac, Whitsunday, Charters Towers, Rockhampton, Maranoa and North Burnett. Isolated infestations occur in other areas so inquire locally to avoid harvesting crops that contain parthenium weed.

Border crossing sites - agricultural machinery

TownPhone number
Goondiwindi Dip Yards (07) 4671 1227
Hebel (07) 4625 0916
Mungindi (02) 6753 2323

Please note:
All other crossings are by appointment with the closest office. All offices require 48 hours notice of your intention to present machinery for inspection. To notify offices, ring and leave a message on the answering service. Machinery can only be inspected during daylight hours.

Cleaning checklist

This checklist is provided for your convenience so that you can keep a record as your machine is cleaned. At the border, you will be required to sign a declaration that each of the relevant areas below have been cleaned. You should also clean any other areas of a machine or vehicle that are capable of carrying plant material.

Parts of harvesters that must be cleaned

Rotary harvester:

Rotary harvester

Conventional harvester:

Conventional harvester

The following areas of grain harvesters — matched to the diagrams above  — must be cleaned to remove soil and plant material.

All harvesters


1. The area under the skid plate. (At the border, access to this area must be provided, preferably by removal of the skid plates)
2. Each header knife and finger
3. The auger located horizontally across the header
4. The area behind any cover on the header
5. The area within any belts on any draper front (if fitted)
6. The feeder house
7. The driver's cab compartment floor area
8. The cleaning fan and the area between the bottom of the fan housing and any shield under the fan housing
9. The chassis, including the inside of any chassis rail ledges, back axle-beam and undercarriage areas
10. Any tailing auger
11. Any sieve area, including the full length and width of the grain pan
12. Any grain bin area, including any auger
13. The engine compartment, including the radiator core
14. Any grain or 'repeat' elevator including any cups and rubber flights
15. Any straw spreader or chopper
16. Any tyres and rims

Conventional harvester

17. The threshing or separating area, including the drum and concaves behind the rasp bars and lead-in plates and around concave wires
18. The beater drum, including the area between the drum and walkers
19. The straw walkers, including the beater and the chaff pan, underneath any straw walker and any concealed areas under rubber air flaps

Rotary harvesters

17. The external top and side of the conical section of the rotor cage
18. The areas inside the top of the conical section
19. The threshing or separating area, including along the rotor cage


Bins and Augers
  • Must be empty and clean
Escort and transport vehicles
  • Must be cleaned externally
  • Cabin, tray and any storage boxes must be clean
  • Radiator must be clean