Without the coordinated program aimed at controlling spread, skeleton weed would now be much more abundant and widely established throughout the cereal growing areas.
Skeleton weed is a declared plant which can reduce crop yields by competing for moisture and nutrients (mainly nitrogen).
Declaration categories and management implications
Skeleton weed is declared under section 22(2) of the Biosecurity and Agriculture Management Act 2007.
Whole of the State except Narembeen and Yilgarn
Narembeen and Yilgarn
The Skeleton Weed Program
The Skeleton Weed Program is a coordinated approach to manage skeleton weed in Western Australia. It is delivered by the Department of Primary Industries and Regional Development (DPIRD) under arrangement with the Grains, Seeds and Hay Industry Management Committee. The Committee acts under the Biosecurity and Agriculture Management Industry Funding Schemes (Grains) Regulations 2010 to manage prioritised pests affecting the grains industry.
Services provided under the program are only available to landholders who contribute to the Grains, Seeds and Hay Industry Funding Scheme through the sale of grain, seed or hay. Landholders not under the scheme but who have skeleton weed on their properties are still required to meet their obligations under the program but at their cost.
|All landholders need to prevent the movement of seed and/or root fragments from their properties in produce (grain, seed and hay), |
wool, machinery and vehicles.
What the program provides to assist landholders
- Identification of suspected skeleton weed plants.
- Technical assistance and advice for the eradication and/or management of skeleton weed on your property.
- Assistance and advice on summer and winter herbicide application.
- Mapping of infestations.
- Assistance with searching new skeleton weed finds and previously infested paddocks.
- Support from DPIRD and Local Action Group staff.
Assisting Western Australian landholders to eradicate skeleton weed and to prevent its further spread within the State.
- Improve landholders’ ability to find and eradicate skeleton weed.
- Increase landholders’ awareness of skeleton weed as a highly undesirable weed.
- Widely publicise descriptions and pictures of skeleton weed to help landholders identify infestations.
- Inform landholders about the most up-to-date techniques available for the management and eradication of skeleton weed.
- Encourage local grower groups, Local Action Groups (LAGs), to participate in cooperative surveillance and reporting of infestations.
- Encourage LAGs to assist in the management and eradication of skeleton weed in their local areas.
- Implement practical compliance regimes in affected areas.
- Provide landholders with incentives to report infestations.
- Provision of winter control treatments where landholders are compliant with program requirements.
The Program has very effective management options
Local Action Groups (LAGs)
A LAG is a network of local farmers in a district affected by skeleton weed, and who have a shared interest in helping other landholders around them cope with the issues skeleton weed presents.
Each LAG applies annually to DPIRD for funds from the approved Skeleton Weed Program budget which is endorsed by the Grains, Seeds and Hay Industry Funding Committee. They aim to promote awareness of skeleton weed, support local landholders with skeleton weed and assist them with management and eradication.
They liaise between landholders and DPIRD to provide input into management of local non-compliance issues and formulate local/regional strategies to deal with skeleton weed within the framework of the state-wide program. Some groups also appoint a LAG Coordinator to work with landholders and in conjunction with DPIRD to undertake operational activities.
Local Action Groups are designed to provide you with additional support. Check with your local DPIRD office for the name of your nearest LAG representative.
There is an extensive local support network for you to call on to assist you identify and help manage skeleton weed effectively
Finding information and advice
Communication with your local DPIRD office, your Local Action Group and your neighbours is integral to achieving skeleton weed eradication on your property.
There is a lot of information available to landholders who find skeleton weed on their land, and a lot to remember, too. If you are unsure of what to do, there are several avenues for you to follow.
In the first instance, your local DPIRD or LAG office can assist. You will be given reference material containing all the information you need to manage and eradicate skeleton weed from your property. Take the time to read it, and make a note of any additional questions that come to you later.
Regular communication with your local DPIRD officer and/or LAG coordinator is essential to ensure you are aware of all your obligations, and what support the program provides. Most of the information given to you by your local DPIRD officer and/or LAG coordinator is also available on the DPIRD website, including this Management Guide.
If you live in an area where skeleton weed is prevalent, neighbours may be able to assist you.
Visit DPIRD’s website: agric.wa.gov.au/skeletonweed
Skeleton weed at a glance
Skeleton weed (Chondrilla juncea L.) is a perennial daisy-like plant that develops from a rosette into a sparsely-leafed, erect plant of up to 1m tall. Erect, branched stems, with little or no foliage, are produced from early October, giving the plant an untidy-look. The rosette and the adult plant exude sticky white sap when cut.
Rosette leaves vary in shape, but barbed lobes remain a key feature
Rosette leaves 5–10cm long present hairless barb-like lobes that point backwards towards the centre of the rosette.
A rosette can be sparsely or densely-leafed, depending on plant age, soil type and how extensive the root system has become. In late spring, stems form and the rosette usually dies off, though a healthy rosette with a well established root system may persist well into summer if there is adequate soil moisture.
Summer rain or high residual soil moisture will encourage old rosettes to re-emerge, even after chemical treatment.
Can have prominent leaves along the stem in good growing conditions
Mature plants have an extensive root system. The tap root can be over 2m long and the lateral roots can radiate up to 50cm from the main tap root.
The plant develops one or more wiry-branching hairless stems growing up to 1m tall. Stems present stiff, downward-pointing bristles at the base. Leaves, if present, are narrow and elongated. Plants can live for several years; stems dying off in late summer as seeds mature. Summer rain may cause regeneration and further seed production.
Lateral root fragments as small as 5 to 10mm can generate new plants. These fragments are usually dragged by farm machinery.
Each petal presents small teeth across its blunt tip
Flowers are bright yellow and daisy-like with 9–12 petals. Individual flower heads are about 20mm wide. Flowers appear on short stalks, in the angle between the plant stem or branch and a leaf or bract. They may occur singly or in clusters of two to five flowers.
Flowers are found along the full length of the branches and at the tip of the main stem, appear from December to May.
A healthy, mature plant produces 10000 to 20000 seeds
Seeds are arranged in ten or eleven seeds per flower. Each seed is 5mm long, with a white parachute attached to the top (to aid wind dispersal). Seeds are grooved, acting like ‘teeth’ to catch on wool, hair or fur.
Seeds are fragile and susceptible to mould and bacteria (causing desiccation in unfavourable weather conditions), and predation by insects and birds.
If adequate summer rainfall occurs, seeds germinate quickly, but usually die if there are no follow up rainfall events. If no rain falls during summer and the seed remains viable and survives predation, it will germinate in the following autumn or winter.
Seeds rarely survive more than 12 months under field conditions, so there is no long-term seed bank.
Skeleton weed features
Where does skeleton weed grow?
Skeleton weed is mainly found in crop and pasture paddocks but can also be found growing in various types of environments including road verges, railway lines, industrial sites, tree plantations and bush areas.
Mature plant growing in industrial yard
Plant with elongated stems from herbicide or frost damage
Skeleton weed can be difficult to spot among crops
Plant growing alongside rail line
Plants confused with skeleton weed
Flatweed and smooth catsear (Hypochaeris spp.)
Hypochaeris species have more than 11 yellow petals
Flatweed is a short-lived perennial, and smooth catsear is an annual plant. Hybrids of these two species exist throughout the south of the State.
Wild lettuce (Lactuca serriola L.)
Wild lettuce has deeply lobed leaves
A biennial plant, seen in townsites, on road verges and in paddocks.
Prickly lettuce (Lactuca saligna L.)
Prickly lettuce grows taller than skeleton weed
Prickly lettuce is a biennial herb often confused with wild lettuce. It is common in townsites and around farm buildings.
Wild turnip (Brassica tournefortii G.)
Wild turnip flowers much
An erect annual plant up to 60cm tall.
Wild mustard, Indian hedge mustard (Sisymbrium orientale L.)
Seeds are contained in
An erect annual, sometimes biennial plant, up to 1m tall.
Wild radish (Raphanus raphanistrum L.)
Wild radish flowers much
An erect annual plant up to 1m tall.
Spot the difference...
Surveillance for skeleton weed
Skeleton weed control requires effective monitoring and surveillance.
The effectiveness of skeleton weed control treatments depends on:
- correctly identifying the location of skeleton weed in the paddock
- correctly identifying the growth stage of skeleton weed.
DPIRD has been carrying out targeted surveillance since 2002 with the objective to find infestations in areas considered a high risk of having skeleton weed. This program also raises awareness of the presence of skeleton weed on high risk properties.
Since 2008 DPIRD has increased its surveillance effort to include areas outside of the known infested areas, in an attempt to properly delimit the true extent of skeleton weed infestations across the Western Australian cereal growing districts. The main focus of surveillance is in areas of likely spread, for example shires on the western and southern edges of the current infestation areas.
The surveillance program involves checking a minimum of three paddocks (preferably containing crop stubbles) on each selected property, such that around 300 hectares is searched per property.
The Skeleton Weed Program is also using a “spread modelling” computer program developed to identify properties with a higher risk of having skeleton weed – thus enhancing surveillance searching.
Surveillance helps landholders locate skeleton weed that they may not be aware is present on their property
Report all suspected skeleton weed finds to DPIRD or LAG within 48 hours.
If skeleton weed is confirmed, notify all neighbours of the discovery and location of all infestations within five working days.
Complete a Full Search of all new infested paddocks within 14 days of confirmation.
Complete a Full Search of all current Code 1 paddocks by 31 December.
|Complete a Full Search of all current Code 3 paddocks by 31 January.|
Complete a Surveillance Search of all Code 2, and all paddocks adjacent to Code 1 paddocks from last season by 31 January.
Keep the minimum required search and treatment records and submit with property maps to your local DPIRD or LAG office by 15 February.
Do not cultivate through marked infestations during the first seeding period after discovery of skeleton weed.
|Prevent active movement of skeleton weed by minimising the risk of contaminated produce and equipment moving around and off the property.|
Non-compliance with protocols
By following the protocols to manage skeleton weed, landholders ensure the success of the Skeleton Weed Program. Failure to comply with any of the protocols will result in regulatory management, and this applies to both broad acre and urban landholders.
Regulatory management involves:
- The issuing of a Direction Notice under Section 36 of the Biosecurity and Agriculture Management Regulations 2013. This Notice will require the landholder/manager to complete the nominated search/treatment work as directed and complete and submit fully compliant records to DPIRD within a specified time frame, usually seven days.
- Failure to comply with a Direction Notice will result in the work being carried out by DPIRD under Section 38 of the Biosecurity and Agriculture Management Act 2007, with all associated costs being recovered from the landholder/manager. Prosecution will be considered where there is evidence the landholder/manager has been aware of an infestation and their responsibilities, and has made no effort to comply.
Pest control notices
In the shires of Narembeen and Yilgarn where skeleton weed is declared category C3 (Management), DPIRD can issue a pest control notice under section 31 of the Biosecurity and Agriculture Management Act 2007. The notice will require the landholder to treat the land area, described within the notice, with herbicide to prevent seed set and will negate the need to conduct a search. It will only be issued for paddocks with widespread infestations of skeleton weed.
The landholder will not be eligible for assistance from the program.
Skeleton weed infested properties
The codes for the pasture paddocks remain the same, and the summer searching and winter treatment regimes still apply. However, because no cropping takes place, two additional surveillance searches are required once the paddock becomes a Code 4 paddock.
This mainly applies to areas west of Gingin and Moora. As there is no cropping, fragments of plants are unlikely to be moved and re-establish, so spread is generally only by seeds.
Explanation of paddock codes
New infested paddock/infested last search
First clear search of previously Code 1 paddock
Second consecutive clear search
Third consecutive clear search, possible release from 'infested list'
Surveillance Search of (non infested) suspect paddock or adjacent paddocks, no plants found
* Code 4 paddocks require a ‘paddock audit’ by DPIRD or LAG staff before release from the infested list.
Searching infested paddocks
If you have paddocks already on the infested list you will be issued with an Infested property paddock record for each infested property and paddock details indicating which paddocks require Full or Surveillance searching. Additional guidelines need to be followed:
- Full Search of all Code 1 paddocks.
- Surveillance Search of all paddocks adjacent to Code 1 paddocks from last season.
- Surveillance Search of all Code 2 paddocks.
- Full Search of Code 3 paddocks followed by a search audit is required to progress to Code 4 and release from the infested list.
- Remember to inform your local DPIRD office post-search, to allow an audit prior to stock being introduced.
- Code 1 paddocks should be searched as soon as possible after harvest. It is advisable to allow 5–10 days before searching harvested paddocks as this will allow skeleton weed plants to grow above the stubble; and ideally in early December, before flowering. Search all current Code 1 paddocks by 31 December.
- Search Code 2 and 3 paddocks and paddocks adjacent to Code 1 paddocks from last search season (summer) by 31 January and record details of all searching and plant treatments on your Infested property paddock record. If paddocks adjacent to Code 1 paddocks from last season are on a neighbouring property, your neighbour(s) are responsible for searching them and also need to record their search activities.
- Regular monitoring of all paddocks, infested sites in particular, should be ongoing.
- All paper records, including farm maps indicating paddocks searched and the location of all infestations, must be submitted to your local DPIRD or LAG office by 15 February. Audits will be undertaken on 100 percent of all records.
The Skeleton Weed Program covers the cost of a Departmental or LAG officer to visit your property to confirm the infestation and discuss your obligations, when required
Applicable to all Code 1 paddocks and Code 3 paddocks due for release from the infested list.
- Keep stubble to a maximum height of 45cm to enhance searching and limit the fire risks (particularly in heavy stubble or frosted paddocks).
- Searching while harvesting or spraying is not a Full Search.
- Paddocks should be livestock-free at least four weeks before searching.
- Allow 5–10 days before searching harvested paddocks; this will allow skeleton weed plants to grow above the stubble. Search paddocks as early as possible after this period and ideally in early to mid December – before plants begin flowering.
- Always be prepared to find skeleton weed. Ensure all vehicles used for searching are fully equipped with flagging tape, star pickets and a post driver or drums to mark finds.
- Take a farm/paddock map and pen with you to accurately mark finds as they are found. Search speed should range from 10 to 20km/h, depending on stubble density or pasture density.
- Use only elevated cab, diesel-powered vehicles to reduce fire risk.
- DPIRD recommends a minimum of a 400L firefighting unit to be present whilst searching.
For Code 2 paddocks and paddocks adjacent to:
- Code 1 paddocks from last year
- New find paddocks.
If plants are found:
- Stop and search the immediate area on foot.
- Clearly mark all the infested area with flagging tape, drums, spears or steel posts around each plant; or clumps of plants (refer to section 1 on Marking search squares).
- Clearly mark the infestation on the paddock map.
Marking search squares
Square sizes depend on the number of plants found in the paddock.
Single plant find
- Mark the plant(s) using flagging tape, a star picket or a drum.
- Search thoroughly to ensure there are no other plants, and step out a 20m buffer in all directions as shown. Where adjoining squares with single plants are within 50m of each other, combine the squares into one large square (while keeping a 20m distance between each individual plant and the edge of the square).
- Place star pickets or drums in each corner of the square.
- Mark the find on a farm map and submit with a Record Sheet from your Infested property paddock record to your local DPIRD or LAG office by 15 February.
Multiple plant find
- Where the site contains multiple plants, search thoroughly to locate the extremity of the infestation and mark using flagging tape, star pickets or drums. Step out a 20m buffer from the outermost plants, as shown above.
- Place star pickets or drums in each corner of the square.
- Mark the find(s) on a farm map and submit a Record Sheet from your Infested property paddock record to your local DPIRD or LAG office by 15 February.
All marked squares will be GPS mapped by the Searching contractor or the local DPIRD/LAG officer.
Which search method is required?
Infested property paddock record
- All infestations are to be treated in summer and winter according to Table 3 found in Control of Skeleton weed section. Landholder must provide a full record of searching, plus summer and winter treatments. Infested property paddock records are issued to landholders for this.
- Paddocks with two consecutive clear searches (Code 3 paddocks) must be searched following the Full Search protocol to qualify for release from ‘infested’ status. The Full Search will be audited by DPIRD or LAG staff.
- For pasture paddocks to qualify for release, at least two of the Clear Searches must have been done in a crop year. If no cropping occurs, two additional surveillance searches are required once the paddock becomes a Code 4 paddock.
- All paddocks should be monitored throughout the summer and autumn, to increase the chance of detecting (and treating) plants that emerge in the weeks following the Full Search.
- Landholders with skeleton weed infestations are eligible for assistance if a ‘Landholder Acknowledgment for Assistance’ (LAA) is signed and returned by 10 December each year.
- Follow required search and treatment protocols once identification is confirmed by Departmental or LAG staff.
The above requirements are legal obligations under the Biosecurity and Agriculture Management Regulations 2013.
- Ensure ability to identify skeleton weed plants at various stages of development.
- Maintain vigilance for skeleton weed plants during normal operations and particularly at harvest time.
- Mark the location of any suspected skeleton weed plants and report the finding to the nearest DPIRD or LAG office.
|Finding skeleton weed in your property is not an indication |
of any failing on your part as a farmer.
Skeleton weed is unpredictable and
can spread over long distances due to wind dispersal,
but once identified it can be managed effectively and eradicated
Annual Program changes and Control recommendation updates are described in the Skeleton weed Management Guide Section 2: Skeleton weed Control Program