Friends of Grasslands

supporting native grassy ecosystems


PO Box 987

Civic Square ACT 2608

Commissioner for Sustainability and the Environment
PO Box 356
Dickson ACT 2602


Dear Maxine


Submission: Investigation into the Government's tree management practices and the renewal of Canberra's urban forest


Friends of Grasslands (FOG) writes to request consideration of this late submission to your investigation into Canberra’s urban forest.


The bush of our bush capital – especially grasslands and grassy woodlands – is threatened with invasion by numerous woody weeds, most of which are escapees from ornamental street and garden plantings.


One of FOG’s activities is the restoration of key grassy ecosystem remnants, including Hall Cemetary, Stirling Park and Yarramundi Reach. All of these significant ecological sites are being over run with tree species such as Cootamundra Wattle (Acacia baileyana) and shrub and hedge species like the Cotoneasters (Cotoneaster sp.), threatening biodiversity and diverting vast but inadequate resources to weed control. More alarming is the naturalisation of increasing numbers of new woody weeds for which there is little awareness of the threats they pose nor regulations to prevent their impacts. For instance, as gardening fads change, two deciduous tree species are being extensively planted in Canberra now: Chinese Pistachio (Pistacia chinensis) and Desert Ash (Fraxinus oxycarpa). To illustrate how pervasive the threat is, Chinese Pistachio is being sold by the ACT Government at Yarralumla Nursery, and Desert Ash is in the gardens of Old Parliament House. Both species are beginning to form dense thickets in Stirling Park.


A further concern is the apparent lack of management of woody weeds on roadside verges adjoining nature reserves, suggesting problems of coordination between ACT Government agencies. For instance, the verges of Parkes Way between Black Mountain and the Yarramundi Reach grasslands are heavily infested with woody weeds like Cootamundra Wattle that should be eradicated, which would remove the major source of weed infestations of these ecologically significant lands. Similarly the verges of Barry Drive between Black Mountain and O’Connor Ridge are infested and unmanaged.


The ACT Pest Plants and Animal Act 2005 (PPAA) and its Declaration do regulate many weed species, but this legislation has two major failings:


a)      It depends on ad hoc declarations of the Minister to add new species or change their status in the control schedules, and


b)      There is no effective program for replacing weeds species mistakenly planted in the past.


The best way to conserve our bush from weeds is to remove the sources of weed seeds in existing plantings. As climate changes reduces precipitation and water availability for temperate ornamental species, the weed threat will grow as more species are planted that may tolerate drier conditions enabling survival in the bush.


Hence FOG asks you to consider the following recommendations to the ACT Government to further reduce the menace from woody weeds in street and garden plantings:


1.      Amend the PPAA to make it more flexible, to allow public nominations to a scientific committee who would advise the Minister on whether to add new weed species (such as Chinese Pistachio and Desert Ash) or change their status in the control schedules. This would enable earlier identification and control of emerging weeds;


2.      Establish programs to replace progressively public plantings of tree, hedge and shrub species on the control schedule with suitable non-invasive plants. To manage the resources required this could be staggered by prioritising species or areas of the ACT for action;


3.      Identify public lands adjoining nature reserves (such as road easements) for priority action to remove woody weeds and replant with indigenous species;


4.      Zone new development close to bushland reserves such that only indigenous plants are used in public plantings (akin to the pet control regulations adjacent to parts of Canberra Nature Park);


5.      Over a period of a decade or more, progressively move plants only listed under the PPAA Declaration in column 5, “plants whose propagation and supply is prohibited” to columns 3 for “suppression”. For example, each year two to three species like Cootamundra Wattle would become illegal to propagate, accompanied by community outreach programs to advise on suitable replacement species and “weed swap” events. The ACT Government could subsidize replacement of weed species in the gardens of low income residents;


6.      Add weed management to the voluntary home audits undertaken by ACT Government instrumentalities to save water and energy, to advise ACT residents on the presence of weed species in their gardens and offer replacement plants. A similar service should be offered to public housing tenants, who often live in homes with well established gardens that have species that are now listed as weeds;


7.      Seek to harmonize regulations and programs with neighboring local governments in NSW to control weed species by preventing sale of weed species over a much broader region;


8.      Require nurseries in the ACT to label stock they sell with information on the species’ weed risk; and


9.      Require housing and commercial estate developers in the ACT to landscape initially with indigenous species, increasing the onus on residents and tenants to switch to non-native species at their own cost should they wish to do so.


Thank you for considering these issues. Please contact Jamie Pittock on m. 0407 265 131 should you require further information on any of these points.


Sincerely yours





Geoff Robertson



7 May 2010