Sampling in precision IPM: When the objective is a map

Measuring and understanding spatial variation of pests is a fundamental com ponent of population dynamics. The resulting maps can drive spatially varia ble pest management, which we define as precision integrated pest managemen t (IPM). Precision IPM has the potential to reduce insecticide use and slow the rate of resistance development because of the creation of temporally d ynamic refuges. This approach to IPM requires sampling in which the objecti ve is to measure spatial variation and map pest density or pressure. Interp olation of spatially referenced data is reviewed, and the influence of samp ling design is suggested to be critical to the mapped visualization. Spatia l sampling created problems with poor precision and small sample sizes that were partially alleviated with choosing sampling units based on their geos tatistical properties, adopting global positioning system technology, and m apping local means. Mapping the probability of exceeding a threshold with i ndicator kriging is discussed as a decision-making tool for precision IPM. The different types of sampling patterns to deploy are discussed relative t o the pest mapping objective.