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Abstract: CABALA, a productivity model for temperate plantation eucalypts, accounts for the impact of eucalypt defoliation on growth but does not yet account for differences in damage type. Consideration of both leaf and bud damage may result in a more realistic representation of growth outcomes for sites with different pest ecologies. We tested whether bud, as compared to leaf damage, elicited similar responses in two commercially important eucalypt species. Growth, biomass and physiological responses of young pot-grown plants to artificial removal of approximately 40% of leaf area (L treatment) or both leaves and buds (LB treatment) was assessed over a 4month period of recovery. We identified that responses to defoliation were similar between the two species (Eucalyptus globulus and Eucalyptus nitens). Time series analysis highlighted that growth (height and stem diameter) was significantly reduced by defoliation during the study, which was more pronounced following LB treatment than L alone. At the end of the study, leaf area, stem height and diameter increment were not significantly affected by treatment, but total above-ground, stem biomass and foliar N were. This suggests that changes in patterns of biomass allocation occurred to maintain leaf area and capacity for light interception. Increased photosynthetic rate, which occurred for plants of both defoliation treatments but to a greater extent for the LB than L treatment, also contributed to recovery following defoliation. There was no evidence that photosynthetic rate increase was driven by changes in foliar nitrogen or chlorophyll, as there was not a statistically significant and strong relationship between the two factors. These results give us confidence that the process-based models used to predict the impacts of defoliation on productivity (1) can assume similar responses to defoliation for E. globulus and E. nitens and (2) should account for differences in physiological responses to foliage and bud damage. [Copyright &y& Elsevier]

The potential to use plantation-grown Acacia mangium for solid-timber products is limited by heartrot, caused by decay fungi. A rapid method of surveying logs stacked in the plantation following harvest was developed which is an alternative to time-consuming whole tree destructive assessments. Logs were randomly chosen from the stacks using a transect method, the cut-ends of the logs were assessed (2199 logs in total) and heartrot severity was scored on a 1–4 scale. Surveys of harvest-age A. mangium were completed in five Indonesian locations to assess heartrot incidence and severity. The incidence of heartrot in the main stem was significantly different between some regions, ranging from 6.7% in East Kalimantan up to 46.7% in West Java. The proportion of each defect type (1–4) did not show a consistent trend across the sites. A combination of differences between plantation management (e.g. pruning), age and climate in these five regions explain the differences in heartrot incidence and severity. [Copyright &y& Elsevier]

Introduction Subcutaneous emphysema is the presence of air/gas within the subcutaneous tissue plane. Though there are numerous causative factors, benign subcutaneous emphysema is rare. Case report We report a very rare case of benign subcutaneous emphysema following an insect bite on the forearm of a 48-year old man. The puncture area was erythematous and the emphysema extended to the whole arm, axilla and superior mediastinum. Despite, conservative management, the patient had residual discomfort and erythema around the puncture site. Surgical debridement resulted in resolution of symptoms. Discussion Subcutaneous emphysema affecting an isolated limb is extremely rare. It is vital to differentiate it from life-threatening soft-tissue infections secondary to a gas-forming organism. Immunodeficiency states are key factors in the development and the outcomes of patients with subcutaneous emphysema. Medical management successfully resolves symptoms in the majority of cases. However, surgical debridement of the puncture site and surrounding fibrotic tissue has been advocated for those with persistent symptoms. Conclusion This case highlights a rare cause of benign subcutaneous emphysema, highlighting key issues surrounding its management for a successful outcome. [ABSTRACT FROM AUTHOR]