Timber in Malaysia has been produced from tropical rainforests that were recognized as one of the highest biodiversity hotspots. Trees of timber species larger than 50 cm in trunk diameter at breast height (cutting limit) have been harvested in ongoing selective logging operation in Malaysia. The harvesting lowered remaining adult tree density, which inhibits pollen travel from a tree to others by pollinator insects. This is a critical issue to produce healthy seeds, because mother trees at lowered population density show frequent self-fertilization that produce less vigorous seeds. Therefore, we have surveyed pollen dispersal pattern of several dipterocarps to estimate pollen dispersal and male fecundity parameters for a simulation of selective logging. The simulation showed that multiple cutting limits are required with respect to each pollinator symbiosis, because dipterocarps with different pollinators showed different pollen dispersal pattern.
