Wood represents the defining feature of forest systems, and often the carbon in woody debris has a long residence time. Globally, coarse dead wood contains 36-72 Pg C, and understanding what controls the fate of this C is important for predicting C cycle responses to global change. The fate of a piece of wood may include one or more of the following: microbial decomposition, combustion, consumption by insects, and physical degradation. The probability of each fate is a function of both the abiotic environment and the wood traits of the species. The wood produced by different species varies substantially in chemical, micro-and macro-morphological traits; many of these characteristics of living species have 'afterlife' effects on the fate and turnover rate of dead wood. The colonization of dead wood by microbes and their activity depends on a large suite of wood chemical and anatomical traits, as well as whole-plant traits such as stem-diameter distributions. Fire consumption is driven by a slightly narrower range of traits with little dependence on wood anatomy. Wood turnover due to insects mainly depends on wood density and secondary chemistry. Physical degradation is a relatively minor loss pathway for most systems, which depends on wood chemistry and environmental conditions. We conclude that information about the traits of woody plants could be extremely useful for modeling and predicting rates of wood turnover across ecosystems. We demonstrate how this trait-based approach is currently limited by oversimplified treatment of dead wood pools in several leading global C models and by a lack of quantitative empirical data linking woody plant traits with the probability and rate of each turnover pathway. Explicitly including plant traits and woody debris pools in global vegetation climate models would improve predictions of wood turnover and its feedback to climate.

Summary 1.Wildfires strongly influence the biotic composition and carbon cycle of many ecosystems. Plant species provide the fuel for wildfires, but vary widely in their flammability. This study aimed to determine what plant characteristics control leaf litter flammability and to clarify how they are related to other functional traits. 2. Litter flammability varied across 14 tree species occurring in a mosaic of five floristic associations. 3. Differences in heat-release rate between species were driven by leaf size, from smallleaved conifers, casuarinas and acacias to large-leaved eucalypts and Brachychiton . 4. Large leaves created an open litter-bed structure that burned more rapidly because it was better ventilated. The results on heat-release rate were partitioned according to fundamental principles for the transport of oxygen through a packed fuel bed, showing that heat-release rate scaled linearly with estimated gas-flow rates, as expected in ventilation-controlled fires. 5. Species that were able to resprout after fire had litter that burned more intensely and was more likely to sustain a spreading fire than litter from obligate seeders, and were correspondingly larger-leaved. 6. Many fire-prone wooded ecosystems in the region consist of large-leaved resprouting tree species co-occurring with small-leaved obligate seeders.

The diet and foraging behaviour of an arboreal marsupial, the brush-tailed phascogale (Phascogale tapoatafa tapoatafa), was examined in the jarrah forest of south-western Australia. Radio-tracking was used to confirm the species’ nocturnal foraging habit and to make direct observations of foraging behaviour. Eleven stomachs, and a collection of 45 scats obtained during summer and autumn, were microscopically examined for content. The availability of major prey items (invertebrates found on or under the bark of tree trunks) was quantified. Phascogales proved to be foraging generalists, and their diet predominantly consisted of invertebrates. Some invertebrate taxa appeared to be preferred but few taxa were avoided. Active pursuit of vertebrates was negligible. However, the species appears opportunistic, and scavenging of vertebrates may contribute to the diet. Nectar was also taken, appearing to be a particularly prized but rare and patchy food source. It is suggested that the current and former distributions of this species have been constrained by both the seasonal reliability of rainfall and the diversity of food resources.

Some plants have traits that cause them to be more flammable than others, influencing wildfire spread and fire regimes. Some of these plant traits have been identified through laboratory-scale experiments. We built a numerical model that could quantify the extent of these effects on flammability. Here we present that model and use it to investigate the effect of phosphate content on the flammability of leaves. The model used finite-element methods and was based on heat transfer and thermal decomposition kinetics. Predictions were compared with three laboratory experiments involving ignition of leaf or cellulose samples. We then ran simulations of two situations through which leaf phosphate could influence wildfire spread: horizontal fire spread and crowning. The ignition time and maximum fuel gap that could be bridged by a flame front was predicted. Two key results emerged. (1) The importance of leaf phosphate in laboratory studies of ignition depends on the rate of sample heating, with the strongest effect under slow heating. (2) In the context of wildfires, phosphate was predicted to have modest effects compared with other plant traits influencing moisture content, leaf construction and angle of display.

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