A dynamical systems model for poly-cyclic foliar forest pathogens


  • Graeme Wake
  • Nari Williams Scion, Forest Protection Rotorua
  • Tony Pleasants Al Rae Centre for Genetics and Animal Breeding, Massey University




Tree disease, epidemiology, systems model


A simple systems model is proposed to understand and quantify the onset and epidemiology of red needle cast in radiata pine. This disease is impacting much of the New Zealand forestry estate being driven through the production of self-replicating spores which are dispersed with water. The model is at present deterministic, not spatially or age-structured, nor dependent on environmental or seasonal effects. This model shows the clear existence of calculable thresholds for disease proliferation and elimination, showing it has captured the essential components of the biological mechanisms. It is to be used to identify thresholds for infection to spread or retract. Further it will provide a base model from which we can fit and then predict experimental outcomes. References
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Author Biographies

Nari Williams, Scion, Forest Protection Rotorua

Senior Researcher, Scion

Tony Pleasants, Al Rae Centre for Genetics and Animal Breeding, Massey University

Research Fellow, Al Rae Centre for Genetics and Animal Breeding





Proceedings Engineering Mathematics and Applications Conference