Abstract:
The cultivation of gaharu affected by genetic factor, silviculture treatment, and habitat condition, it also influenced by its level of resistance to pests and diseases. At the beginning of plant growth, gaharu is susceptible to Heortia vitessoides caterpillar that attacks leaves and lead the death of the plants because its became leafless. The neccesary of controling actions determined by the ammount of damage that can be generated at one attack period. The purpose of this researce is to predict the age of Heortia vitessoidescaterpillar based on the growth of caterpillar in some parameters which are body lenght,diameter of body, and diameter of head. The metodhs of the research are study of literature, field observations, observations, and measurments. The data were analyzed descriptively by connecting the growth of Heortia vitessoides on the third parameters measured with the age of caterpillar using scatter plot to determine the parameters which is closer to linear to predict the age of Heortia vitessoides caterpillar. The result showed that the phase of Heortia vitessiodes larvae can reach up to 24 days where destructive phase is for 20 days and the last 4 days is fasting phase. The size of Heortia vitessoides body diameter can be used as a reference to predict the age of the caterpillar rather than the body lenght and the diameter of head parameters. Based on the scatter plot, there are a close relationship between the diameter of body with the age of caterpillar with R2 values as much as 0.973. If the damage condition of the tree is less than 50% and the age of caterpillar is no more than half of the phase, the controling action is not urged to carried out.
