DEPARTMENT OF PRIMARY INDUSTRIES

Fireweed madagascariensis

Victorian Alert Weed Fact Sheet biology Type of weed: Garden escape/agricultural. Lifeform: Short-lived perennial herb. Description: Stems: Plant grows 300-500 mm tall in ideal conditions with multiple branches from a central root base. Leaves: The leaves are green to bright green, alternately spaced and clasped around the stem. Leaves vary in length, normally 20-60 mm long but may reach lengths up to 120 mm in larger . Leaves are linear shaped with distinctive serrated edges. Flowers: Fireweed has small, daisy-like fl owers

Image: R. Watson Image: Jim Dellow - NSW DPI that are bright yellow in colour and grow up to 20 mm in diameter. Each fl ower normally has 13 thin petals surrounding a disc fl oret. The Botanical name: Senecio madagascariensis. plant’s multi-branching stems lead to a mass Synonyms: Senecio incognitus, Senecio burchellii. of individual fl ower spikes and fi reweed can Common name: Fireweed. produce several hundred fl owers per plant. Alternatives: groundsel, Madagascar ragwort. Plants are able to fl ower year round under the Family: . right conditions and they only take 6-10 weeks Relevant relatives: The Senecio genus contains a large number to form fl ower buds after germinating. of , many of which are weeds, and includes ragwort (Senecio Seeds: S. madagascariensis seeds are typical of jacobaea) and the African daisy (Senecio pterophorus) declared the daisies; small, light, prolifi c and long lived. noxious weeds in Victoria. Two native Senecio species, variable Seeds are 1-3 mm long with a rod-shaped tip groundsel (Senecio pinnatifolius) and fi reweed groundsel (Senecio which is covered in small hairs, allowing them linearfolious), look very similar and may be confused with the to catch onto animals and machinery. At the introduced fi reweed (Senecio madagascariensis). seed’s base is a clump of fl uffy, bristle like hairs, allowing effi cient windblown seed dispersal. Each fl ower can produce 100-150 seeds, each with high viability and the ability to germinate immediately after release. As each plant is multi- branching, fl owering can be extended for weeks, maximising the plant’s seed production. Seeds will germinate readily following disturbances such as bushfi res or cultivation, and plants can establish before other desirable pasture grasses get the chance to emerge. Roots: Fireweed has a single, branched taproot growing to 200 mm deep, from which the plant sends out multiple stems.

Weed Alert! Fireweed Senecio madagascariensis

Victorian Alert Weeds Importance & impacts Impacts: Ecosystems, waterways and agriculture: What are Victorian Alert Weeds? Fireweed has the potential to out compete more desirable agricultural grasses and remnant native Victorian Alert Weeds are potential weeds of the vegetation. The plant’s toxicity to cattle and horses future. They may pose a serious threat to Victoria’s and the ease at which it colonises disturbed sites agricultural and natural assets or could affect and over grazed paddocks makes this a very human health. Some of these weeds are thought troublesome weed for farmers and graziers. Fireweed to occur in small numbers in Victoria and are still is an exceptionally drought tolerant plant, often one eradicable. Other species are yet to reach Victoria, of the fi rst plants to germinate following drought but present a serious threat if they were to arrive. breaking rains (Sindel 1986). Weed Spotters help the Department of Primary Social value and health impacts: Fireweed’s Industries validate the distribution of these weeds. pretty, golden fl owers may make it a desirable choice Weed Spotters are individuals trained to look for to grow in a garden. Fireweed is toxic to cattle and report high priority Weed Alert species in and horses, and although it is less toxic for sheep Victoria. They are recruited from the community, and goats, animals that eat it can eventually lose government or industry. condition. The effects of fi reweed on humans are relatively unknown. Health hazards: Fireweed is toxic to cattle and horses and when the plant is grazed at low densities, cattle experience irreversible damage and quickly lose weight and condition (through liver damage). Why is this species a When fi reweed becomes the dominant species in a pasture, cattle usually die within 6-12 months (Sindel Victorian Alert Weed? 1986). Sheep and goats are not as susceptible to the plants toxicity but their condition will diminish if Fireweed has an attractive golden daisy fl ower, they graze fi reweed for long periods. Caution should not out of place in a country-style garden. In be taken when handling or removing the plant as fact, this plant looks so similar to local native there may be possible health impacts for humans. daisies that it could mistakenly be nourished and cared for. Unfortunately for farmers and graziers, Importance: fi reweed’s toxicity to horses and cattle make it Fireweed is a declared a plant they would not want to encourage. Its Weed legislative status: noxious weed in New South Wales, the Australian lightweight seeds are easily spread by wind and Capital Territory and Queensland. machinery, which has helped it invade vast tracks of agricultural land in costal New South Wales Signifi cance of the weed in : Fireweed and Southern Queensland. Fireweed is toxic to is already a signifi cant weed in costal agricultural areas horses and cattle, be it growing in the paddock or of New South Wales and costs their dairy industry at in dry hay, and it has the potential to hitch a ride least $10 million dollars per annum (Radford et al to Victoria as a contaminant of grain and fodder 1995). S. madagascariensis infestations exist as far including during times of drought. Fireweed is south as Eden in New South Wales and, according to extremely fast growing, opportunistic and is often scientifi c modelling, it would also be well adapted associated with overgrazed paddocks. Fireweed to Victorian conditions. It is surprising that Victoria has been known to germinate, fl ower and produce has not already been inundated with naturalised viable seed up to four times in a single growing populations of fi reweed, given it is well adapted to season, making them a very effi cient invader. growing in cooler climates with low rainfall. Publicity Fireweed populations are travelling rapidly south of fi reweed in the southern states has been minimal along the Hume and Pacifi c Highways from New and could mean the Victorian public are not actively South Wales and Weed Spotters in the North East on the look out for this species. of Victoria will need to be particularly vigilant. Permitted/prohibited entry into Australia: Senecio madagascariensis plants and seed are permitted entry into Australia, subject to certain conditions. For more information see the AQIS ICON import conditions database at www.daffa.gov.au/ aqis/import/icon-icd or call 1800 020 504. Victorian Weed Risk Assessment: A weed risk assessment of Senecio madagascariensis listed it as a high risk species due to its invasive potential and the plant’s suitability to Victoria’s climatic extremes. Growth & spread

Reproduction and dispersal: Fireweed Origin: Madagascar and coastal . reproduces almost exclusively by seed but can also reproduce vegetatively, with roots sprouting Where it grows: Fireweed is a well adapted from the stems if they come into contact with the colonising species, emerging in pasture, roadsides, ground (Allan et al 2005). Fireweed can alter its urban areas and wastelands following a major germination, adapting its growing and fl owering disturbance. behaviours to suit changing environmental conditions (Sindel 1986). Seeds are both windblown Weedy distribution in Australia and and readily attach to machinery and animal fl eece, overseas: Fireweed has naturalised at three allowing for dispersal over large distances. locations in Victoria; Studley Park at Kew, along the banks of the Yarra River in Melbourne and on Rate of growth and spread: S. the Balnarring coast at Somers (Australia’s Virtual madagascariensis is a plant with extremely rapid Herbarium 2006). These populations have been growth. Seeds can germinate immediately after assessed and appear to have been eradicated, dispersal, followed by rapid plant growth, and but will require continual monitoring for years to can bolt to fl ower and be ready to seed all within come. Climatic modelling suggests there is a high 6–10 weeks. This rapid development enables three likelihood infestations could persist across the of four distinct generations per growing season majority of Victoria. S. madagascariensis is already and makes long-term eradication of the species heavily distributed along the coastal fringes of NSW, extremely diffi cult. from Eden in the south through to the northern outskirts of Brisbane. The plant’s seeds are easily Seed bank/propagule persistence: Seeds may spread by wind and machinery and infestations remain viable in the soil from three to fi ve years, have been recorded spreading south from New but may last as long as 10 years (Sindel et al 1998). South Wales which poses a real threat for Victoria. Overseas, fi reweed has become a problem weed in coastal , Hawaii and Japan.

Growth calendar Jan Feb Mar April May June July Aug Sept Oct Nov Dec

Flowering

Seeding

Germination

Rosette growth

Notes: Growth calendar is broadly based on behaviour and timing of plant changes, either from overseas populations, or from limited populations in Australia. Actual behaviour of plants may differ, depending on climate and geographical location.

Introductory pathway to Australia: Fireweed along roadways and into agricultural areas. While is common place in New South Wales and is well the most likely methods of fi reweed introduction adapted for Victorian conditions. The plant is into Victoria are across state borders (either as a attractive and colourful, similar looking to native contaminant of hay or machinery, wind dispersed yellow fl owering daisies, and it has the potential seed or deliberate plantings) there are other to be a popular garden choice. The population potential pathways. Large infestations in Hawaii of S. madagascariensis at Studley Park in Kew pose a threat and the plant’s sticky seeds may was believed to have been planted by accident, arrive as contaminates on the shoes and clothing following misidentifi cation as a native shrub (N. of travellers. The native fi reweed populations Walsh pers. comm.). Fireweed is a prolifi c seeder of Madagascar and South Africa could also help and has easily dispersed propagules, so there spread this weed into Australia, arriving as a seed is a high probability for spread out of gardens, or contaminant on machinery or in imported grain. Fireweed Senecio madagascariensis

Choosing alternative species

When choosing an alternative plant, attempt to source local native (indigenous) species from a nursery/garden centre in your area. Advice can also be sought from Sustainable Gardening Australia - a not for profi t organisation, promoting responsible plant choices - call (03) 9850 8165 or visit their website at www.sgaonline.org.au.

Further information about fi reweed can be found on the DPI website at www.dpi.vic.gov.au or check the references listed below. If you suspect you have found Senecio madagascariensis, report it to your local Weed Alert Contact Offi cer on 136 186.

References: Acknowledgments: Stuart Roberton (Victorian Allan, H., Launders, T. and Walker, K. (2005). DPI, Wodonga), Robin Adair (Victorian DPI, ‘Fireweed. Primefact 126’. (New South Wales Frankston), Lynda Ayres and Jim Dellow (NSW Department of Agriculture). DPI, Orange), John Reid and Neville Walsh (Royal Botanic Gardens, Melbourne). This fact sheet was Australia’s Virtual Herbarium (2006). ‘Australia’s prepared by Richard Plant and Stuart Roberton, Virtual Herbarium’. (Centre for Plant Biodiversity December 2007. Research, Council of Heads of Australian Herbaria). Accessed Online 03/05/2007. http://www.cpbr.gov.au/cgi- bin/avh.cgi

Radford, I., King, D. and Cousens, R. (1995). A Survey of Senecio madagascariensis Poir. (Fireweed) Density in Pastures of Coastal New South Wales. Plant Protection Quarterly 10, 107 – 111.

Sindel, B., Radford, I., Holtkamp, R. and Michael, P. (1998). The Biology of Australian Weeds. 33. Senecio madagascariensis Poir. Plant Protection Quarterly 13, 2 – 15.

Sindel, B. M. (1986). The Ecology and Control of Fireweed (Senecio madagascariensis Poir.). Plant Protection Quarterly 1. 163 – 172. Printed on 100% recycled paper. Printed on 100% recycled

Published by the Victorian Government Department of Primary Industries Melbourne, March 2008 © The State of Victoria Department of Primary Industries 2008. This publication is copyright. No part may be reproduced by any process except in accordance with the provisions of the Copyright Act 1968. Authorised by the Victorian Government, 1 Treasury Place, Melbourne, Victoria, 3000 Australia. ISBN 978-1-74199-795-8 Disclaimer This publication may be of assistance to you but the State of Victoria and its employees do not guarantee that the publication is without fl aw of any kind or is wholly appropriate for your particular purposes and therefore disclaims all liability for any error, loss or other consequence which may arise from you relying on any information in this publication.

For further information, visit the DPI Website at www.dpi.vic.gov.au or contact the DPI Customer Service Centre on 136 186