Incidence of heartrot in harvest-age Acacia mangium in Indonesia, using a rapid survey method

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.