Palerang
Indicator: Pest Plants
Results for this indicator are also available for [an error occurred while processing this directive]
Please note: Text or data highlighted in this colour represent an update to this indicator for the period 2008/09.
What the results tell us for Palerang
Palerang Council identified five high priority weeds within the Council area. All of the priority species have the potential to reduce primary productivity, while two species are poisonous or potentially harmful to livestock. All the priority weed species also have the potential to adversely impact on biological diversity and native vegetation, including six listed threatened ecological communities in the Council area. The overall areas of infestation of all priority species decreased during the current reporting period.
Council carried out weed control activities for five high priority weeds during the reporting period, and achieved reductions in overall densities for all species. No information was available on the distribution and abundance of weeds within various national parks and other reserves over the reporting period, or on weed management activities undertaken by the New South Wales (NSW) Department of Environment and Climate Change (DECC) in those areas. No data were available on weeds or weed management in the two state forests located partly within the Council area.
Pest plant infestations
Five pest plant species were identified as high priority pests in Palerang Council area during the reporting period: African Lovegrass (Eragrostis curvula), Blackberry (Rubus fruticosus), English Broom (Cytisus scoparius), St John's Wort (Hypericum perforatum) and Serrated Tussock (Nassella trichotoma).
All of the priority weed species have the potential to reduce primary productivity. St John's Wort and Serrated Tussock are also poisonous or potentially harmful to livestock. The five priority weed species also have the potential to negatively impact on biodiversity and native vegetation communities, including six threatened ecological communities that may occur in the Council area. The location and approximate area and density of infestation of the five major pest plants in Palerang Council area are summarised in Table 1.
Table 1. Priority pest plant species in Palerang Council area, July 2004 to June 2008 (opens in new window)
Council carried out weed control activities for the five high priority weeds listed above during the reporting period, and achieved reductions in overall densities for all species.
Twenty national parks and other conservation reserves are located wholly or partly in Palerang Council area. At least 13 plant species were considered to be weeds in these areas during the previous reporting period. No information was available to assess the distribution and abundance of priority weeds within conservation areas during this reporting period. No information was available regarding the presence of pest plants within state forests located wholly or partially within the Council area.
Pest plants as threatening processes
A number of the priority weed species have the potential to negatively impact on biodiversity and native vegetation. Palerang Council area may have occurrences of six threatened ecological communities listed Nationally or in NSW (DECC, 2008b; DEWHA, 2008a). All of these threatened ecological communities are considered at risk from invasive weeds (DECC, 2008b, DEWHA, 2008a). These include exotic perennial grasses, pasture weeds, noxious weeds and environmental weeds. Weeds compete with native plants for resources such as light and nutrients, and can aggressively invade areas, displacing native plants and animals. The control of weeds at these priority sites can help recover threatened species. No information is available to assess the impact of weeds on these threatened plant communities.
A final determination to list 'Invasion of native plant communities by exotic perennial grasses' as a key threatening process under the Threatened Species Conservation Act 1995 was made by the NSW Scientific Committee during the previous reporting period. The grass species included Serrated Tussock, which is a species of concern within the Shire. The impacts of exotic perennial grasses as outlined in the Scientific Committee's final determination include (DECC 2008a):
- competition with or displacement of native species
- local and regional declines in many native plant species and communities.
According to the DECC website, there are seven priority actions under the "habitat management: weed control" recovery strategy in the Palerang Council area. These actions apply to seven threatened species (five plants, one marsupial and one bat) DECC 2008c).
Pest plant control activities by NSW Government agencies
No specific information was available regarding control programs undertaken on public land by NSW Government agencies. The assessment made in Palerang Council’s Draft Noxious Weeds Management Report for 2007-08 includes:
- conservation areas are reasonably well controlled by National Parks & Wildlife Service
- Sydney Catchment Authority has made improvements to their land management during the reporting period through increased requirements of leaseholders to control pest plants
- railway reserve land is poorly controlled and poses a severe threat to weed spread and re-infestation. Whilst there is a relatively small area that requires control, the land has a large frontage to other properties due to its narrow linear nature
- travelling stock reserves have some control by Rural Lands Protection Board, however considering that they often contain a relative abundance of native species due to their long term low grazing pressure their ecological value could probably be better managed
- State Forestry areas often have large infestations of blackberry which can be difficult to control
- other crown land managed by the Department of Lands has only limited budget allocated for weed control
Pest plant control activities by Palerang Council
The control of all the high priority pest plants within the Council area is undertaken according to regional and sub-regional Weed Management plans. Regional Weed Management plans cover the area for which the Southern Tablelands and South Coast Noxious Plants Committee is responsible. Regional Weed Management plans for the Southern Tablelands and South Coast Region developed during the reporting period, in which the Palerang Council is involved, covered five pest plant species (see Table 2).
Table 2. Pest plant control in Palerang Council area, July 2004 to June 2009 (opens in new window)
Table 2 was updated to include data for 2008/09.
Control actions for the major weeds within Palerang Council area focused largely on preventing spread into clean areas, controlling all rare and isolated infestations, strategically reducing infestations in marginal and core areas, implementing protocols to prevent seed spread, education, facilitating coordination between land managers and protecting vulnerable high conservation areas. Weed control methods for priority species within the Council area predominantly involved the use of herbicide, with some ploughing for Serrated Tussock. The main objective was to control spread of all species on all lands within the Council area.
Expenditure on and effectiveness of pest plant control
All funding for control of the five priority weed species on Council-managed land was sourced from Council only, with the exception of a $6000 grant from NSW Department of Primary Industries for control of Broom and Gorse. Council has no data on the expenditure for weed control on private land or on public land managed by other government agencies. The Catchment Management Authorities managed targeted funding programs. Murrumbidgee CMA provided funds to Palerang Council for a riparian restoration program that incorporated removal of willows.
Affected area treated is estimated as overall area over the reporting period. No information is available on the breakdown of the percentage of total area treated for each of the priority weeds by local Government, community groups and individuals.
The weed management strategy is effective, however due to continuing drought conditions it is difficult for desired species to compete with weeds. The longer term financial impact of the drought also reduces the ability for land managers to control weeds, along with the rising cost of chemicals, fuel, fertiliser etc.
Council carried out weed control activities for the five high priority weeds listed above during the reporting period and generally achieved reductions in overall densities for all species.
About the data
A spread sheet was supplied to each Council, with fields summarising priority plant species, the status of control plans and their objectives. The spreadsheet also included a field nominating the types of control methods used and the areas that were treated, either by community groups, individuals or local government. A field describing the change in relative abundance within the density classes of high (75-100% cover), medium (20-74% cover) and low (1-19%) was also included. In compiling the Pest Plant indicator chapters, the authors compared this data to data for the previous reporting period (2000-2004), as well as sourcing information available on the DECC website. In some cases, missing data impeded comparison.
References
DECC—see Department of Environment and Climate Change
Department of Environment and Climate Change (NSW) (2008a) NSW Scientific Committee—Final Determination, Invasion of Native Plant Communities by Exotic Perennial Grasses—Key Threatening Process Declaration, NSW Department of Environment and Conservation, 29 September 2008, http://www.nationalparks.nsw.gov.au/npws.nsf/Content/Invasion+of+native+plant+
communities+by+exotic+perennial+grasses+key+threatening+process+declaration
Department of Environment and Climate Change (2008b), Threatened Species – species, populations and ecological communities in NSW , search on endangered ecological community, viewed 29 September 2008, http://www.threatenedspecies.environment.nsw.gov.au/tsprofile/home_species.aspx
Department of Environment and Climate Change (2008c), Threatened Species – species, populations and ecological communities in NSW , Recovery and threat abatement, Bombala Shire Council, viewed 13 October 2008, http://www.threatenedspecies.environment.nsw.gov.au/tsprofile/pas_lga_recovery_details.aspx?
lga=Bega%20Bombala%20Shire%20Council&type=habitat+management:+weed+control
Department of Environment, Water, Heritage and the Arts (Commonwealth) (2008a), Biodiversity, search on endangered ecological community, viewed 29 September 2008, http://www.environment.gov.au/biodiversity/index.html
Southern Tablelands and South Coast Noxious Plants Committee (2001a) Regional Weed Management Plan for Aquatic Noxious Weeds 2001–2006, Southern Tablelands and South Coast Noxious Plants Committee, viewed 29 September 2008,
STSCNPC—see Southern Tablelands and South Coast Noxious Plants Committee
