ABSTRACT
This chapter provides basic concepts of sampling, discusses types of population density estimates, describes characteristics of samples and associated sampling statistics, and shows methods for developing sampling plans or programs. Practical sampling programs have been developed for insects associated with field and orchard crops. The chapter discusses the sampling techniques with reference to insects. A sample or sampling unit is the fraction of the habitable space from which insect counts are made. The sampling universe can be assumed to contain a known number of sampling units. The size of the sampling unit, to some extent, will be determined by the choice of the sampling device. The method employed to sample insects using a sampling unit constitutes a sampling technique. Sampling programs indicate which sampling unit to use, how many sampling units to use, and when to sample for insects, and the spatial distribution or dispersion of insects based on sampling data.
