Mechanical Mastication Reduces Fuel Structure and Modelled Fire Behaviour in Australian Shrub Encroached Ecosystems

Shrub encroachment of grassland and woodland ecosystems can alter wildfire behaviour threaten ecological values. Australian fire managers are using mechanical mastication to reduce the risk in encroached but yet evaluate its effectiveness or impact. We asked: (1) How does fuel load structure change following mastication?; (2) Is likely affect rates spread flame heights?; (3) What is impact on flora species richness diversity? At thirteen paired sites (masticated versus control; n = 26), located Victoria, Australia, we measured properties (structure, hazard) floristic diversity (richness Shannon’s H) 400 mP2 plots. To quantify effects mastication, data were analysed parametric non-parametric sample techniques. Masticated grouped into two categories, 0–2 3–4 years post treatment. Fire was predicted Dry Eucalypt Forest Model. Mastication with follow-up herbicide reduced density taller shrubs, greater than 50 cm height, for at least 4 years. The most recently masticated (0–2 years) had an almost 3-fold increase dead fine loads 11-fold coarse forest floor compared controls. Higher still evident after Changes produced a reduction heights from 22 m 5–6 under severe weather conditions, no rate spread. Reductions height would be beneficial suppression could damage property wildfires. did not have meaningful effect native diversity, promoted abundance some exotic species.