Weed of the Month – Bitou Bush

Bitou bush

This is a Weed of National Significance and while occurrence on the coast in Noosa is rare, it is an important one to recognize. It should to be reported to Biosecurity Queensland on13 25 23 within 24 hours of being found.

Alert

Have you seen Bitou bush?

Be on the lookout for Bitou bush and report it to Biosecurity Queensland. Early detection and reporting are the key elements in controlling Bitou bush.

Bitou bush flower

Bitou bush flower

Bitou bush in coastal dunes

Bitou bush in coastal dunes

Bitou bush infestation

Bitou bush infestation

Bitou bush leaves and flower

Bitou bush plant form

All photos copyright Queensland Government

Native to southern Africa, bitou bush is an attractive, bright green perennial shrub. It occurs in all Australian states and territories except the Northern Territory, and is the dominant vegetation along much of the New South Wales coastline. Bitou bush out-competes and, in many cases, totally eliminates, native flora on coastal dunes.

Bitou bush was originally planted in New South Wales and parts of Queensland to revegetate coastal dunes following sand mining.

Boneseed (Chrysanthemoides monilifera ssp. Monilifera) is a close relative to bitou bush and while not yet present in Queensland it is one of the Weeds of National Significance alongside bitou and all reporting requirements for bitou are also required for sightings of boneseed.

Bitou bush and boneseed are restricted invasive plants under the Biosecurity Act 2014.

Scientific name

Chrysanthemoides monilifera subsp. rotundata

Description

  • Attractive, bright green perennial shrub up to 5m tall.
  • Flowers are yellow, chrysanthemum-like, up to 20mm in diameter, on short stalks, clustered on ends of branches.
  • Stems are much branched with woody upper stems, often purple.
  • Leaves are 20-80mm long, teardrop shape, irregularly serrated on edges, practically hairless except for cottony down on young leaves. Grow on short stalks and alternate along stems.
  • Fruit is spherical with green fleshy skin that changes from brown to black on maturity.
  • Fruit has 1 seed, which is hard and bone-like in colour and texture when ripe.
  • Boneseed is a close relative of bitou bush. It is an erect shrub. Leaves are less rounded and more teethed than bitou bush. Boneseed flowers have 3-8 petals, seeds are bone-coloured.

Habitat

  • Occurs mainly in sandy, coastline areas.

Distribution

  • Found in Wide Bay area and in isolated spots on Noosa headland; on North and South Stradbroke Island, Moreton Island and southern Moreton Bay Islands; and scattered along Gold Coast beach strip.

Life cycle

  • Produces up to 50,000 seeds per plant per year.
  • Germinates at any time of year, particularly after good rain.
  • Flowers intermittently, but mainly May-July.
  • Seeds remain viable for at least 2 years.
  • Plants flower within 6 months of germination.

Affected animals

  • Native birds
  • Native animals

Impacts

Environmental

  • Out-competes and often eliminates native flora on coastal dunes.
  • Forms dense green blankets preventing native seedlings from growing.
  • Destroys habitats of many native birds and animals.

How it is spread

  • Spreads rapidly by birds eating fruit.

Cited in: Weed Spotter’s Online Bulletin, May 2021

Information source:

https://www.business.qld.gov.au/industries/farms-fishing-forestry/agriculture/land-management/health-pests-weeds-diseases/weeds-diseases/invasive-plants/restricted/bitou-bush

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