Studies were conducted on the spatial distribution of the sugarcane shoot borer, Chilo infuscatellus Snellen. Distribution was aggregated and described by the negative binomial model with a fixed mean size. Aggregated distribution probably resulted from environmental heterogeneity. The five quadrants of the field, i.e. north, south, east, west and central did not differ significantly in borer population. The optimum sample size, based on Iwao's formula, was 126 plants of 6 tillers each. The relevance of these findings to the management of C. infuscatellus is discussed.
