Quick Facts

Quick facts

• Fringed Dodder (Cuscuta suaveolens) is a leafless, twining, parasitic plant that forms a dense mat of growth over its host plant.
• Its thread-like twining stems are usually yellowish-green, cream or whitish in colour and have small suckers which penetrate the host plant's stems or leaves and extract nutrients.
• Fringed Dodder is a potentially serious pest of crops and sown pastures, particularly legumes such as lucerne and clover.
• It also attacks native plants growing in pastures and natural areas, and has the potential to become an environmental weed.

What Does It Look Like?

What is it?

Fringed Dodder (Cuscuta suaveolens) is a short-lived, leafless, twining, parasitic herb that forms a dense mat of growth over other plants. Its twining and branching stems are generally yellowish-green, cream or whitish in colour. These stems are hairless, thin and thread-like in appearance. They have small suckers (called haustoria) which are used to penetrate the host plant's stems or leaves and extract nutrients (Navie 2004).

The small flowers (3–4 mm long) are cream to white in colour and somewhat bell-shaped. These flowers are borne in loose few-flowered clusters on stalks 3–6 mm long. They have five sepals and five pointed petals which are partially fused together. The petal lobes are usually held upright with inward-pointing tips. The flowers also have five stamens and two styles that are topped with tiny globular stigmas.

The small greenish-yellow rounded capsules (2–3 mm across) contain up to four seeds. These seeds are more or less rounded in shape (1.5 to 2 mm across) and have a granular surface texture (Navie 2004).

For further information and assistance with identification of Fringed Dodder contact the herbarium in your state or territory.

Flower colour

White

Growth form (weed type/habit)

Vine

Where it currently grows? Preferred habitat

Fringed Dodder is a potentially serious parasitic pest of numerous crops that can grow in a wide range of environmental conditions. It may also be found growing on plants and other weeds in grasslands, along roadsides and in saline habitats (Cunningham et al. 2003; Navie 2004).

Are there similar species?

Fringed Dodder is very similar to the other introduced (i.e., Cuscuta campestris, C. planiflora and C. epithymum) and native (i.e., C. australis, C. chinensis, C. tasmanica and C. victoriana) Dodders that are present in Australia. Fringed Dodder can be distinguished from most of these species by its relatively loose flower clusters, with the flowers being borne on stalks 3–6 mm long. This feature is only shared by Tasmanian Dodder (C. tasmanica), which can be separated by its larger blunt-tipped petals (4–6 mm long) (Johnson 1992; Navie 2004).

Fringed Dodder is also relatively similar to the native Dodder laurels (Cassytha spp.), which are also parasitic twiners. However, the Dodder laurels have flowers with three petals and three sepals (instead of five), 6–9 stamens (versus five), their stems are often green and hairy and they have fleshy one-seeded fruit (Navie 2004).

Why Is It A Weed?

What are its impacts?

Fringed Dodder is one of seventeen sleeper weeds identified by the Bureau of Rural Sciences (following consultation with the Australian Weeds Committee) which could have nationally significant impacts on agriculture if allowed to spread.

Agriculture: Fringed Dodder is a potentially significant parasite of crops and pastures. It mainly attacks Lucerne, Clovers and other legumes, but has also been recorded on Carrots, Onions and other species. Infested areas are often quarantined, causing considerable financial loss, and contaminated produce has a reduced value (Parsons and Cuthbertson 2001; Cunningham et al. 2003).

Native ecosystems: Fringed Dodder also has the potential to be an environmental weed as it is known to infest native vegetation in south-eastern South Australia and New South Wales (Cunningham et al. 2003). For example, it was recently recorded from Lignum (Duma florulenta, formerly Muehlenbeckia florulenta) thickets and gidgee (Acacia cambagei) woodlands in Culgoa National Park in the central north of New South Wales (Hunter 2005).

How does it spread?

Fringed Dodder reproduces by seed and sometimes also by stem fragments. The seeds and stem fragments are mostly spread to new areas in contaminated agricultural produce and are also washed downstream by water movement. Seeds may also be dispersed in mud attached to vehicles and can pass through the digestive tract of animals intact (Parsons and Cuthbertson 2001; Navie 2004).

What is its history in Australia?

Like all of the other introduced Dodders, it is thought that Fringed Dodder was accidentally introduced into Australia as a contaminant of agricultural produce (Parsons & Cuthbertson 2001).

How To Manage It?

Best practice management

Non-chemical control: Like with all parasitic plants, prevention of introduction and spread is vital to the management of Fringed Dodder. This is best achieved with good quarantine measures.

Physical control: Contaminated pasture seeds, hay and grain can introduce the plant to unaffected properties or to clean areas, so any contaminated produce should be destroyed. Livestock and contaminated machinery can also spread the seed to new areas.

Mechanical control: Machinery should be cleaned before moving to other paddocks and stock grazing on areas known to be infested with Fringed Dodder should be kept in quarantine for at least two days before they are moved to Dodder-free pastures (Trounce et al. 1998).

Land management: Crops or pastures that are severely infested (e.g., Lucerne and Clover) should be replaced or rotated with less susceptible or resistant crops or pastures where practical. Where crops or pastures are used in rotations to control Fringed Dodder, Lucerne or susceptible legumes should not be sown again for at least five years (Trounce et al. 1998).

Chemical control: Fringed Dodder can be controlled by cutting the host plant as close as possible to ground level and burning it. Contact herbicides can be used to rapidly desiccate the standing crop and destroy the Dodder plants. These herbicides act by quickly killing green plant material and also provide dry fuel for a fire (Cunningham et al. 2003, Trounce et al. 1998).

Please see the Australian Pesticides and Veterinary Medicines Authority for chemical information http://www.apvma.gov.au

Does it have a biological control agent?

NO

When does it grow? (lifecycle/growth calendar)

Like other Dodders, seeds of Fringed Dodder can germinate in spring, summer and autumn, but most germination takes place in late spring. Germination will not occur without the stimulus provided by the close presence of a suitable host plant. This is because seedlings do not possess roots and will die unless they quickly become attached to a host plant. By parasitising the host plant, the seedlings are able to twine rapidly and commence flowering quickly (Parsons and Cuthbertson 2001; Cunningham et al. 2003). Flowering occurs from late spring through to early autumn (Navie 2004).

Where Is It Found?

Which states and territories is it found?

NSW, SA, TAS, VIC

What areas within states and territories is it found?

Fringed Dodder is naturalised in some parts of south-eastern Australia (e.g. in New South Wales, southern Victoria, Tasmania and south-eastern South Australia) (APC 2007). In South Australia, approximately 100 hectares of native vegetation in the south-eastern parts of the state is infested with Fringed Dodder. This infestation is mainly located on heavy, moderately saline soils subject to flooding in winter.

Fringed Dodder was also reported from several localities in Victoria and inland New South Wales (e.g., in the Maitland, Adelong and Narrabri districts) prior to 1930, however its current distribution in these states is unknown as habitats have either become more saline or have been converted to pasture. However Fringed Dodder was recently recorded from lignum thickets and gidgee woodlands in Culgoa National Park in the central-north of New South Wales (Hunter 2005).

A single infestation was recently also found in a red clover seed crop in the Forth district in Tasmania, though this population is thought to have been eradicated (Cunningham et al. 2003).

Where does it originate?

Fringed Dodder is native to the southern parts of South America (i.e., southern Brazil, Argentina, Chile and Uruguay) (GRIN 2007).

National And State Weed Listings

Is it a Weed of National Significance (WONS)?

NO

Where is it a declared weed?

NSW, SA, TAS, VIC, WA

Government weed strategies and lists – Weeds Australia

Is it on the National Alert List for Environmental Weeds?

NO

Government weed strategies and lists – Weeds Australia

Is it on the Agricultural Sleeper List?

YES

Government weed strategies and lists – Weeds Australia

Names And Taxonomy

Main scientific name

Cuscuta suaveolens

Other scientific names (synonyms)?

Does it have other known common name(s)?

Dodder, Chilean Dodder, Chile Dodder, Lucerne Dodder, Alfalfa Dodder