Diameter patterns of 5-year old Karas (Aquilaria malaccensis) agroforestry stands

The work conducted in this study is based on a preliminary data collection for assessing a soil status in a 5-year old Karas agroforestry plantations in Rembau, Negeri Sembilan, Malaysia. Three agroforestry components involved in this study include (1) Karas (Aquilaria malaccensis) monoculture, (2) Karas intercropped with lemongrass, and (3) Karas intercropped with guava. Three replicative plots measuring at 6 m × 5 m were established for each component. Each plot consists of a total of 90 Karas trees. The diameter at breast height (DBH) of Karas trees was measured in each plot. From the field measurements, the means of tree DBH in all three plots are 5.74 cm, 4.23 cm and 6.65 cm, respectively. Analysis of variance (ANOVA) revealed that there is a significant difference in the mean DBH of Karas tree between components (P≤0.05). Karas intercropped with guava recorded a significantly greater DBH than the other two components (P≤0.05). This could be due to the intercropping effects of Karas with different components of agroforestry system. The results from this study will be used for subsequent investigation in the assessments of growth performance of Karas under different intercropping components.