NSW Bitou Bush Threat Abatement Plan - Department of ...

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Threat Abatement Plan - Invasion of native plant communities by Chrysanthemoides monilifera
The staged approach must:
< be planned before any control is undertaken, with all stages clearly marked and the
timing of each stage determined, preferably incorporated into a site-specific
management plan (see below)
< only control areas for which there are resources available to undertake the subsequent
stages, including most importantly the follow-up treatment of seedlings. Irrespective of
the initial control measure implemented, follow-up treatments are required to control
recruitment (as described by Vranjic 2000).
7.4.1 Littoral rainforest - an example of a staged approach
Bitou bush poses a serious threat to littoral rainforest. It threatens littoral rainforests in two main
ways. First, it invades the margins, where it competes with or suppresses the species that protect
the rainforest. The exposed margins are then subject to further degradation particularly on the
seaward fringes, which are exposed to salt spray and desiccating winds. Second, bitou bush
establishes in canopy gaps where it suppresses regrowth and reduces recruitment of native plants.
Canopy gaps can occur naturally or through the competitive effect of bitou bush at the margins.
Long-term monitoring of bitou bush-infested littoral rainforests shows that where small gaps in
the canopy occur, lantana and native species may replace bitou bush. However, in larger gaps and
on the margins, bitou bush remains the dominant species (Hunter pers. comm.).
The staged approach is necessary in the control of bitou bush invasion of margins to ensure that it
does not result in exposure of the littoral rainforest following the removal of bitou bush from
where it replaces the forest’s protective vegetation. Thus stage 1 would involve a staggered
removal of bitou bush from the forest edge, especially on the seaward side of littoral rainforests,
to maintain the forest’s protective buffer from wind and salt spray. For the control of bitou bush in
canopy gaps, stage 1 would involve the systematic removal of all plants from within the canopy,
especially in forest gaps, while stage 2 would involve the removal of bitou bush from the forest
margins, and stage 3 removal from the surrounding habitat.
7.5 Site-specific management
Best practice management guidelines (Vranjic 2000) and the NSW bitou bush strategy (NPWS
2001a) both emphasise the importance of site-specific strategies or management plans for the
control of bitou bush. Previously there has been no framework for developing such strategies, but
rather information was presented on a series of bitou bush densities and invaded habitats along
with a range of control options (see Vranjic 2000).
The use of site-specific management strategies should not result in broader management
objectives being compromised. To avoid this occurring and still ensure effective site management,
a framework has been developed for compiling site-specific management strategies/plans (see
below) as well as a proforma for preparing a site-specific management plan (see Appendix 9).
7.5.1 A framework for site-specific management plans
While the development of site-specific management plans is dependent on local factors and
conditions, each plan [for the purposes of this TAP] must be based on a core set of attributes.
These form a framework for the development of site-specific management plans for the control of