Blue billygoat weed
Ageratum houstonianum
family
Asteraceae
origin
Exotic
declaration
NIL
For information only
Common names
Ageratum, Blue billy goat weed, Blue billygoat weed, Blue top, Flossflower.
A short-lived herbaceous plant with softly hairy stems and leaves. Its toothed leaves are oppositely arranged at the base of the stems, but are often alternately arranged at the top of the stems. Its flower-heads are usually blue (occasionally pink or whitish) and lack any obvious 'petals'these flower-heads have very hairy bracts and numerous long narrow projections. Its tiny black or brown 'seeds' (about 2 mm long) are topped with five whitish, hair-like, scales.
Impact
Impact
Blue billygoat weed (Ageratum houstonianum) is regarded as an environmental weed in Queensland and New South Wales. This garden escape frequently invades bushland and other natural environments resulting in substantial changes in native plant communities. It displaces indigenous plants, and possibly also native animals, and is particularly invasive along waterways and in riparian vegetation.In Queensland, blue billygoat weed (Ageratum houstonianum) is currently of most concern in the south-eastern parts of the state, where it is ranked among the top 200 environmental weed species. It is listed as an environmental weed in numerous local authorities in this region (e.g. in Redland Shire, Maroochy Shire, Cooloola Shire, Caboolture Shire, Burnett Shire, Hervey Bay City and Maryborough City) and also invades conservation areas. For example, blue billygoat weed (Ageratum houstonianum) is one of only a few introduced species that have colonised undisturbed or relatively intact open forest vegetation within Brisbane Forest Park.
Location
Location
Characteristics
Characteristics
Similar Species
Similar Species
Blue billygoat weed (Ageratum houstonianum) is regarded as an environmental weed in Queensland and New South Wales. This garden escape frequently invades bushland and other natural environments resulting in substantial changes in native plant communities. It displaces indigenous plants, and possibly also native animals, and is particularly invasive along waterways and in riparian vegetation.In Queensland, blue billygoat weed (Ageratum houstonianum) is currently of most concern in the south-eastern parts of the state, where it is ranked among the top 200 environmental weed species. It is listed as an environmental weed in numerous local authorities in this region (e.g. in Redland Shire, Maroochy Shire, Cooloola Shire, Caboolture Shire, Burnett Shire, Hervey Bay City and Maryborough City) and also invades conservation areas. For example, blue billygoat weed (Ageratum houstonianum) is one of only a few introduced species that have colonised undisturbed or relatively intact open forest vegetation within Brisbane Forest Park.
