title: Modelling Tradescantia fluminensis to assess long term survival.
abstract: We present a simple Poisson process model for the growth of Tradescantia fluminensis, an invasive plant species that inhibits the regeneration of native forest remnants in New Zealand. The model was parameterised with data derived from field experiments in New Zealand and then verified with independent data. The model gave good predictions which showed that its underlying assumptions are sound. However, this simple model had less predictive power for outputs based on variance suggesting that some assumptions were lacking. Therefore, we extended the model to include higher variability between plants thereby improving its predictions. This high variance model suggests that control measures that promote node death at the base of the plant or restrict the main stem growth rate will be more effective than those that reduce the number of branching events. The extended model forms a good basis for assessing the efficacy of various forms of control of this weed, including the recently-released leaf-feeding tradescantia leaf beetle (Neolema ogloblini).
authors.affiliation: Biomathematics Research Centre, University of Canterbury , New Zealand.
authors.forename: Alex
authors.initials: A
authors.lastname: James
authors.affiliation: AgResearch , Lincoln , New Zealand ; School of Biological Sciences, University of Canterbury , New Zealand.
authors.forename: Sue M
authors.initials: SM
authors.lastname: Molloy
authors.affiliation: Biomathematics Research Centre, University of Canterbury , New Zealand.
authors.forename: Agate
authors.initials: A
authors.lastname: Ponder-Sutton
authors.affiliation: Biomathematics Research Centre, University of Canterbury , New Zealand.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Plank
authors.affiliation: AgResearch , Lincoln , New Zealand.
authors.forename: Shona L
authors.initials: SL
authors.lastname: Lamoureaux
authors.affiliation: AgResearch , Lincoln , New Zealand.
authors.forename: Graeme W
authors.initials: GW
authors.lastname: Bourdôt
authors.affiliation: School of Biological Sciences, University of Canterbury , New Zealand.
authors.forename: Dave
authors.initials: D
authors.lastname: Kelly
keywords: Biocontrol; Branching process; Invasive species; Stochastic model