title: A long-term experimental case study of the ecological effectiveness and cost effectiveness of invasive plant management in achieving conservation goals: bitou bush control in booderee national park in eastern australia.
abstract: Invasive plant management is often justified in terms of conservation goals, yet progress is rarely assessed against these broader goals, instead focussing on short-term reductions of the invader as a measure of success. Key questions commonly remain unanswered including whether invader removal reverses invader impacts and whether management itself has negative ecosystem impacts. We addressed these knowledge gaps using a seven year experimental investigation of Bitou Bush, Chrysanthemoides monilifera subsp. rotundata. Our case study took advantage of the realities of applied management interventions for Bitou Bush to assess whether it is a driver or passenger of environmental change, and quantified conservation benefits relative to management costs of different treatment regimes. Among treatments examined, spraying with herbicide followed by burning and subsequent re-spraying (spray-fire-spray) proved the most effective for reducing the number of individuals and cover of Bitou Bush. Other treatment regimes (e.g. fire followed by spraying, or two fires in succession) were less effective or even exacerbated Bitou Bush invasion. The spray-fire-spray regime did not increase susceptibility of treated areas to re-invasion by Bitou Bush or other exotic species. This regime significantly reduced plant species richness and cover, but these effects were short-lived. The spray-fire-spray regime was the most cost-effective approach to controlling a highly invasive species and facilitating restoration of native plant species richness to levels characteristic of uninvaded sites. We provide a decision tree to guide management, where recommended actions depend on the outcome of post-treatment monitoring and performance against objectives. Critical to success is avoiding partial treatments and treatment sequences that may exacerbate invasive species impacts. We also show the value of taking advantage of unplanned events, such as wildfires, to achieve management objectives at reduced cost.
authors.affiliation: Fenner School of Environment and Society, The Australian National University, Canberra, Australian Capital Territory, Australia; ARC Centre of Excellence for Environmental Decisions, The Australian National University, Canberra, Australian Capital Territory, Australia; National Environmental Research Program, The Australian National University, Canberra, Australian Capital Territory, Australia; Long-term Ecological Research Network, Terrestrial Ecosystem Research Network, The Australian National University, Canberra, Australian Capital Territory, Australia.
authors.forename: David B
authors.initials: DB
authors.lastname: Lindenmayer
authors.affiliation: Fenner School of Environment and Society, The Australian National University, Canberra, Australian Capital Territory, Australia; ARC Centre of Excellence for Environmental Decisions, The Australian National University, Canberra, Australian Capital Territory, Australia; National Environmental Research Program, The Australian National University, Canberra, Australian Capital Territory, Australia.
authors.forename: Jeff
authors.initials: J
authors.lastname: Wood
authors.affiliation: Fenner School of Environment and Society, The Australian National University, Canberra, Australian Capital Territory, Australia; ARC Centre of Excellence for Environmental Decisions, The Australian National University, Canberra, Australian Capital Territory, Australia; National Environmental Research Program, The Australian National University, Canberra, Australian Capital Territory, Australia; Long-term Ecological Research Network, Terrestrial Ecosystem Research Network, The Australian National University, Canberra, Australian Capital Territory, Australia.
authors.forename: Christopher
authors.initials: C
authors.lastname: MacGregor
authors.affiliation: ARC Centre of Excellence for Environmental Decisions, University of Queensland, Brisbane, Queensland, Australia; School of Natural Sciences & Trinity Centre for Biodiversity Research, Zoology, Trinity College, University of Dublin, Dublin, Ireland.
authors.forename: Yvonne M
authors.initials: YM
authors.lastname: Buckley
authors.affiliation: Parks Australia, Department of the Environment, Jervis Bay Village, Jervis Bay Territory, Australia.
authors.forename: Nicholas
authors.initials: N
authors.lastname: Dexter
authors.affiliation: Parks Australia, Department of the Environment, Jervis Bay Village, Jervis Bay Territory, Australia.
authors.forename: Martin
authors.initials: M
authors.lastname: Fortescue
authors.affiliation: School of Plant Biology, University of Western Australia, Crawley, Western Australia, Australia; ARC Centre of Excellence for Environmental Decisions, University of Western Australia, Crawley, Western Australia, Australia.
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Hobbs
authors.affiliation: Fenner School of Environment and Society, The Australian National University, Canberra, Australian Capital Territory, Australia; ARC Centre of Excellence for Environmental Decisions, The Australian National University, Canberra, Australian Capital Territory, Australia; School of BioSciences, The University of Melbourne, Melbourne, Victoria, Australia; Department of Ecology, Evolution and Behavior, University of Minnesota, St Paul, Minnesota, United States of America.
authors.forename: Jane A
authors.initials: JA
authors.lastname: Catford
mesh_terms: D000818:Animals; D019659:Asteraceae / Q000502:physiology*; D001315:Australia; D003247:Conservation of Natural Resources / Q000191:economics / Q000379:methods; D003362:Cost-Benefit Analysis; D003663:Decision Trees; D017753:Ecosystem; D005390:Fires; D006540:Herbicides; D006801:Humans; D058865:Introduced Species / Q000191:economics*; D000068316:Parks, Recreational; D058728:Weed Control / Q000191:economics / Q000379:methods*
chemical_list: D006540:Herbicides