NSW Bitou Bush Threat Abatement Plan - Department of ...

Threat Abatement Plan - Invasion of native plant communities by Chrysanthemoides monilifera
Ainsworth 2000). Seed germination occurs from depths of up to 8 cm (majority up to 5 cm) in the
absence of soil disturbance (Weiss et al. 1998).
Boneseed is fire-sensitive (i.e. is killed by fire), intolerant of water-logged soil conditions, salt
spray and mild frosts. It is relatively short-lived (10–20 years). It has a shallow root system and
unlike bitou bush, is not capable of vegetative reproduction (Adair and Ainsworth 2000).
3.2 Bitou bush and boneseed as environmental weeds
Chrysanthemoides monilifera is an environmental weed in Australia, New Zealand, France, the
Islands of St. Helena (South Atlantic Ocean) and Sicily (Weiss et al. 1998).
3.2.1 Arrival and spread of bitou bush in Australia
The exact date of arrival of bitou bush to Australia is unknown. The first known record is a
herbarium specimen dated 1908, collected from the Stockton area near Newcastle in New South
Wales. It is thought that this infestation originated from ballast carried from South Africa (Gray
1976; Cooney et al. 1982).
From 1946–1968, bitou bush was deliberately planted by the NSW Soil Conservation Service to
stabilise sand dunes along the NSW coast. It was also planted along the northern NSW coast to
stabilise and revegetate coastal sand dunes after they were mined for rutile and zircon (Barr 1965).
Bitou bush was recommended as one of several useful secondary stabilisers for use following
such mining operations (Barr 1965).
The main areas where bitou bush was deliberately planted include Ballina, Byron Bay, Crescent
Head, Diamond Head, Hastings Point, Iluka, Lake Munmorah, Mylestom, Port Macquarie,
Redhead, The Entrance and Tweed Heads. Bitou bush was also planted to stabilise sand dunes
near Broken Hill and Menindee in western New South Wales (Cunningham et al. 1981). It was
also introduced to Lord Howe Island, the first record of which was in 1968 near the dump; today
there are about 1,500 plants scattered across the north and east of the island (e.g. Neds Beach and
Middle Beach). Concerns over the impact of bitou bush have led to an eradication program on
Lord Howe Island being initiated.
Currently bitou bush occurs along most of the NSW coast, with the densest infestations in the
north of the state (NPWS 2001a). It also persists around Broken Hill and Menindee, as well as on
Lord Howe Island. Outside New South Wales it occurs in coastal areas from the Qld/NSW border
to Hervey Bay, on a number of offshore islands in Queensland, and at a limited number of sites in
Victoria.
A comprehensive survey of the distribution of bitou bush in New South Wales in 1981–82
showed that 660 km of the NSW coastline was infested (Love 1984). Of the area surveyed, bitou
bush was the dominant plant along approximately 220 km. The NSW coast was re-surveyed in
2000–01, revealing that the length of coastline infested had increased to 900 km (82%), of which
bitou bush was the dominant plant along approximately 400 km (36%) (Thomas and Leys 2002).
With a few exceptions, bitou bush occurs continuously from the Shoalhaven River north to the
Queensland border, with most of the north coast being heavily infested. South of the Shoalhaven
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