Spatial Variability in Corn Rootworm Distribution in Relation to Spatially Variable Soil Factors and Crop Condition

Numbers of surviving adults emerging from the soil and egg populations of corn (Zea mays L.) rootworms in the soil are known to have variable spatial distributions. Studies have been conducted to examine spatial correlations between com rootworm populations, root injury, crop canopy condition, and observable soil properties, including apparent electromagnetic conductivity, pH, topography, and soil type. Interactions among these factors may exist that mediate year-to-year spatial variation in rootworm populations. Prediction of economic corn rootworm infestation usually depends on the assessment of late summer or fall ovipositing adult populations, rather than actual knowledge of oviposition distribution or within-field distribution of successfully overwintering eggs at the start of the growing season. Management of corn rootworms probably could be improved through better understanding of how spatially variable crop and edaphic factors influence spatial variability of infestations