Plant Protection Quarterly Vol.23(1) 2008 49 period. This information has informed the selection of future bitou bush control sites Coordinated regeneration programs in coastal and facilitated better site management. Despite the success of bitou bush con- vegetation on the Tomaree Peninsula – a decade of trol, secondary weed incursions, includ- bitou bush control ing weeds previously not widely recorded in NSW such as Asystasia gangetica (L.) Mellesa SchroderA, Geoffrey JamesA and Anthony MarchmentB T.Anderson, Crithmum maritimum L., Eryn- A Parks and Wildlife Group, Department of Environment and Climate Change, gium maritinum L. and Tetragonia decumbens Mill, have established in sites where bitou Locked Bag 99, Nelson Bay, New South Wales 2317, Australia. B bush infestations were treated. These sites Port Stephens Council, PO Box 2324, Raymond Terrace, New South Wales occur in proximity to urban townships, 2324, Australia. where refuse dumping and bird disper- sal remain two key vectors for secondary weeds. Dispersal by ocean currents has also been linked to at least two new sec- Abstract ondary weed incursions. Some of these Coordinated weed control programs fo- of priorities. Mapping was replicated in secondary weeds are more diffi cult and cussing on the weed bitou bush (Chry- 2007. After ten years of coordinated bi- expensive to control than bitou bush, thus santhemoides monilifera subsp. rotundata tou bush control, comparisons indicate a increasing original follow-up cost pre- (DC.) Norl.) have been undertaken on signifi cant reduction in the density of bi- dictions. Regardless, once a program has the Tomaree Peninsula on the mid-north tou bush. This includes a 17% reduction commenced, the commitment to continue coast of New South Wales (NSW) since in high density infestations, 44% reduc- follow-up of all weed species is integral. the development of a co-operative con- tion in medium infestations and a 36.7% This includes continuing to support com- trol plan in 1997. The Port Stephens Bitou reduction in light infestations. Whilst the munity engagement as a component of the Bush Management Plan was developed density of the weed has been reduced, the programs. Active community support has by the Port Stephens Coastal Weed Action distribution has increased by 3.5% in the contributed greatly to the success of holis- Group with members from Port Stephens ten year period. This refl ects reinvasion tic weed control at a number of sites. Council, NSW National Parks and Wildlife from infestations outside of the Tomaree Ignoring boundaries and developing Service (now the Department of Environ- Peninsula and illustrates the diffi culties in priorities across land tenure has increased ment and Climate Change), Department controlling dispersal mechanisms such as the success of coordinated bitou bush (and of Land and Water Conservation (now birds and ocean currents. other weed) control. Undertaking pro- Department of Lands) and various com- Programs are prioritized to control bi- grams cooperatively is the most effective munity bush regeneration groups. The tou bush at locations where signifi cant way to deal with landscape weed inva- Plan has taken a cross-tenure approach vegetation communities, such as endan- sion. This program is an example of what to the prioritization of control programs. gered ecological communities and threat- can be achieved when different land man- This has ensured success and enabled the ened plant species occur. Observational agers and community groups can develop implementation of strategic coordinated data collected throughout the control pro- and implement strategies together and programs that utilize consistent control gram has provided important information forge a commitment for consistent follow- methodology. The programs are commit- on the ecosystem resilience of coastal veg- up. Given the continual dispersal of bitou ted to the protection of signifi cant native etation communities following the control bush (and other weeds) and the constant vegetation communities and promotion of of bitou bush. Ecosystem resilience was risk of reinvasion, long-term control will natural regeneration. lower in fore dune and hind dune vegeta- continue to be an ongoing part of manag- Bitou bush infests over 1600 ha of the tion with high density (>50%) bitou bush ing coastal vegetation communities on the 10 000 ha Tomaree Peninsula. Distribu- infestations. These areas require revegeta- Tomaree Peninsula. tion and density mapping was fi rst un- tion to stabilize dunes and reduce second- dertaken in 1997 using aerial photogra- ary weed invasion. Coastal vegetation Acknowledgments phy and ground truthing. Density was communities (such as coastal heath and We thank all of the community groups mapped at the shrub layer level in four forest on clay soils) demonstrated higher who have dedicated their time and en- categories; high >50%, medium 10–50%, ecosystem resilience and were able to re- ergy towards removing weeds across the light 1–10% and scattered <1%. This in- cover from light, medium and high den- Tomaree Peninsula. formation assisted in the establishment sity bitou bush invasion over the ten year