Document ID: chunk:federal_register_of_legislation:F2012L02359:body:0:p3
Version: federal_register_of_legislation:F2012L02359
Segment Type: other
Provision Reference: 
Character Range: 6825–9998

While this TAP aims primarily to abate the threat to key assets, it also recognises that these grasses have wider environmental impacts as well as social, cultural and economic impacts.

This TAP further acknowledges that the five listed grasses may threaten areas outside northern Australia, and that other high-biomass invasive grasses may pose a threat to biodiversity. Although this TAP has been developed to address the KTP identified above, the concepts and approaches contained in this TAP may be applied to other localities or grasses, or to protect other assets where appropriate opportunities arise.

The Australian Government acknowledges that some introduced grasses have high production and economic values and, when appropriately managed and contained for pastoral purposes, do not necessarily contribute to the decline of environmental assets in northern Australia.

1. Threat abatement plan to reduce the impacts on northern Australia's biodiversity by the five listed grasses

1.1. Description of the process and its impacts

The KTP addressed by this national TAP covers five species of introduced grasses: gamba grass (Andropogon gayanus), para grass (Urochloa mutica), olive hymenachne (Hymenachne amplexicaulis), perennial mission grass (Cenchrus polystachios syn. Pennisetum polystachion) and annual mission grass (Cenchrus pedicellatus syn. Pennisetum pedicellatum). Each of these grasses was imported into Australia for testing and/or use as pasture grasses. However, these invasive high-biomass species can increase fuel loads and/or alter nitrogen cycling and water availability within systems (Douglas et al., 2004; Rossiter et al., 2004; TSSC, 2009), resulting in ecosystem degradation, habitat loss and biodiversity decline. Table A provides a list of threatened species and ecological communities that are under immediate threat from the grasses.

1.2. Managing the threat

Weed management is based on the principles of prevention, eradication, containment and asset protection. Preventing invasive plant species from establishing is the most cost-effective form of weed management. Where infestations are small or newly established, the goal should be intense suppression aiming to eradicate. In areas where this is not feasible or economically viable, suppression seeking containment is important to lessen the impacts of the grasses and to prevent them from spreading into unaffected areas. Within core or large infestations, management should focus on identifying and protecting priority assets. Management necessarily involves all levels of land managers from Australian Government agencies, state and territory agencies, local councils, community groups, individual land managers and the general public.

Understanding the population biology of an invasive plant is important when developing effective management strategies. Knowledge of factors such as plant longevity, methods of spread, seed bank viability, and recruitment patterns allows the development of predictive models which can then be used to develop surveys to predict pathways of spread and assist with the detection of outlier populations and new incursions (Campbell