What is orange hawkweed?
Orange hawkweed (Hieracium aurantiacum) is a perennial herb native to Europe. It is a member of the daisy family (Asteraceae) and has bright orange flowers with square-edged petals, making flowering plants easy to identify.
The plants lie close to the ground and leaves grow outwards from the centre, in a flat circular pattern, forming a rosette. The weed can spread via seeds or stolons, which are horizontal plant stems or runners that lie across the ground and grow from buds in the rosette.
Why is orange hawkweed a problem?
Orange hawkweed is a problem because it
- impacts on endangered ecological communities
- out competes native species and creates monocultures
- threatens species habitat, natural landscapes and cultural heritage in Kosciuszko National Park.
Orange hawkweed is listed as Prohibited Matter under the NSW Biosecurity Act 2015. Hawkweeds (Hieracium species) have potential to be serious environmental and agricultural threats in the temperate areas of south east Australia, including the Australian Alps. Prompt treatment of known populations of hawkweeds has limited their spread so far.
Orange hawkweed is on the Alert List for Environmental Weeds, a list of 28 non-native plants that threaten biodiversity and cause other environmental damage. Although only in the early stages of establishment, these weeds have the potential to seriously degrade Australia's ecosystems.
Orange hawkweed was historically sold in nurseries as an ornamental plant in New South Wales. It was first recorded as naturalised in 2003. Loss and degradation of native plant and animal habitat by invasion of escaped garden plants, including aquatic plants has been listed as a key threatening process by the NSW Scientific Committee.
Managing orange hawkweed
NSW Orange Hawkweed Strategy has been developed in consultation with a range of stakeholders to address the threats from hawkweed and aims to eradicate orange hawkweed and mouse ear hawkweed from New South Wales.
Currently in New South Wales, orange hawkweed is only known to occur in Kosciuszko National Park and 2 nearby properties. However, there may also be additional unknown infestations outside Kosciusko National Park and a large-scale, cross-tenure surveillance effort is underway to detect and eradicate any new infestations