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Poverty weed: State Prohibited Weed | LC0287 |
Keith Turnbull Research Institute, Frankston
February, 1998 |  |
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Common Name
Poverty weed
Botanical Name
Iva axillaris Pursh
Status
Poverty weed is one of only fourteen weeds proclaimed as State Prohibited Weeds in Victoria. This is the highest category to which a noxious weed can be allocated and means that poverty weed is to be eradicated if possible from the State.
Origin
Poverty weed originated in North America where it is a significant weed of rangelands, cereals, overgrazed pastures, and irrigated crops in Canada and the north-western United States. It has not established on any other continent except Australia. It was first recorded from Newstead in north central Victoria in 1926 and most Australian infestations are in Victoria.
Description
A long-lived perennial herb usually about 20 to 30 cm high, reproducing from both roots and seeds.
Stems - generally erect and branched near the base, may or may not be hairy.
Leaves - 1 to 3 cm long and 1 cm wide, sometimes with a curved or wavy appearance, hairy and mostly lacking stalks ie. growing direct from a main stem, grey-green. Lower leaves opposite, upper leaves smaller and alternate.
Flowers - greenish-yellow, in 5 to 7 mm diameter heads on short stalks from leaf and stem junctions near the top of the plant. Each flower head consists of both male and female flowers.
Seeds - egg shaped, brown or dark grey, 2 to 3 mm long, coarsely surfaced. 6 or 7 are produced in each flower head.
Roots - up to 2.5 m deep. Thick lateral roots produce buds and shoots each year which develop into new plants. The deep roots contain food reserves which allow new growth to produce under drought conditions.
Figure 1. Poverty weed.
Life Cycle
New plants develop form lateral roots in spring each year. Seeds may also germinate at this time of year. Flowering occurs in summer and the top-growth dies off in autumn.
Dispersal
The main means of spread are from earth moving or cultivating equipment dragging root fragments to uninfested areas. Seeds do not particularly aid dispersal but may be caught in mud in animal hooves, equipment, and tyres. Seed does not appear to be harmed by inundation with water.
General
Poverty weed is a strong competitor. In dense infestations it may be the only plant species present. Growth of other species is inhibited or prevented by allelopathic chemicals found in both the roots and leaves of the plant. It has a strong smell and taste, and is not grazed. In North America it causes contact dermatitis in people and contributes to aerial pollen loads which casue hayfever.
Chemical Control
No herbicide products are registered in Victoria to control this weed.
Important
Any person who believes they have located an infestation of poverty weed, regardless of the area, please notify a Catchment Management Officer at a local office of the Department of Natural Resources and Environment.
Reference
Parsons, W.T. and Cuthbertson, E.G. (1992) Noxious Weeds of Australia. Melbourne, Inkata Press.
Acknowledgements
Prepared by Ross Williamson, KTRI, 1996. Revised by Ian Faithfull, KTRI, February 1998.
This note replaces note number PPA0013
The advice provided in this publication is intended as a source of information only. Always read the label before using any of the products mentioned. The State of Victoria and its employees do not guarantee that the publication is without flaw 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.
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