Seasonal dynamics in understorey abundance and carbohydrate concentration in relation to browsing and bark stripping of Tasmanian Pinus radiata plantations

摘要: Abstract Bark stripping in Pinus radiata plantations by Bennett’s wallaby (M. rufrogriseus subspecies rufrogriseus) triggers high rates of tree mortality and reduces crop productivity, causing significant economic losses to the Australian forest industry. shows a marked increase during winter which may be associated with concurrent increases bark soluble sugar concentration. Seasonal abundance alternative forage also contribute bark-stripping incidence. Relationships between seasonal variations quantity quality, periods increased were assessed two P. plantations. Understorey composition, abundance, browsing pressure, sugar, starch total non-structural carbohydrate (TNC) concentrations measured seasonally over period 12 months for each species areas experiencing low levels stripping. A strong general positive association concentrations, particularly exotic grasses Poa annua Holcus lanatus, elevated pressure was found. In contrast content weakly negatively pressure. Ratios concentration sugars significantly positively correlated allocated five sub-groups based on putative chemical physical mechanisms tolerance to, or defence against, herbivory. This sub-grouping lends support effect ratios preference. The current study demonstrates that consistently higher than native understorey represents an available, apparent quality food source wallaby. H. lanatus had comparable are provided they remain sufficient abundance. These results indicative key mechanism driving Tasmania. lend credence implementation browser management strategies (1) short term, provision diversionary feed (2) limiting herbage so time plantation landscape supports lower populations browsers.