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Abstract

Invasive native scrub (INS) has caused major changes to landscapes in Western NSW with

adverse effects on pastoral production and aspects of biodiversity. The reduction in the

incidence of fires since European settlement has contributed to these changes. The priority for

managing INS is to maintain open areas and reduce further increase of invasive native species

density. Effective management of INS will result in a mosaic of native vegetation types in the

landscape creating a diversity of habitats. The control of INS has benefits for production and

the environment with improved native groundcover and soil stability. The management of

total grazing pressure (TGP) before and after burning is crucial to achieving improved

environmental and production outcomes.

The most cost effective way to manage INS is the control of seedling germination events with

fire. Mass seedling germinations occur following prolonged high rainfall events and there is a

limited window of opportunity to manage the seedlings. Seedlings of many invasive native

species are susceptible to fire with almost one hundred percent kill rate when they are less

than thirty centimetres in height. The kill rate with fire dramatically decreases with plants

above thirty centimetres and negligible above fifty centimetres height. Although fire has

limitations in managing INS it is considered to be the only realistic tool to manage seedlings

at a landscape scale.

Effective policy is required to ensure that appropriate fire regimes are encouraged and that

balanced environmental outcomes are achieved. This paper discusses how these policies are

implemented in NSW and the optimal fire management to maintain mosaic landscapes with

the control of INS.