Variation in pesticide use across crops in California agriculture: Economic and ecological drivers.

Pesticide use is a key component of efficient crop production, but is associated with a suite of costs. Understanding the main drivers of pesticide use will help us target research to develop effective alternatives. Although economic models predict, and empirical tests confirm, that the value of the crop being protected is an important determinant of between-crop variation in pesticide use, previous tests of this prediction have examined only modest numbers of crops and have not assessed the relative importance of crop value versus ecological determinants of pesticide use.

An Ecoinformatics Approach to Field-Scale Evaluation of Insecticide Effects in California Citrus: Are Citrus Thrips and Citrus Red Mite Induced Pests?

Experimental approaches to studying the consequences of pesticide use, including impacts on beneficial insects, are vital; however, they can be limited in scale and realism. We show that an ecoinformatics approach that leverages existing data on pesticides, pests, and beneficials across multiple fields can provide complementary insights. We do this using a multi-year dataset (2002-2013) on pesticide applications and density estimates of two pests, citrus thrips (Scirtothrips citri (Moulton [Thysanoptera: Thripidae])) and citrus red mites (Panonychus citri McGregor [Acari: Tetranychidae]), and a natural enemy (Euseius spp.

Does use of pesticides known to harm natural enemies of spider mites (Acari: Tetranychidae) result in increased number of miticide applications? An examination of California walnut orchards.

Integrated pest management (IPM) offers guidelines to reduce spider mite (Acari: Tetranychidae) outbreaks by avoiding pesticides known to be harmful to the natural enemies of spider mites. However, in practice, these guidelines can be inconsistent in their effectiveness. The project examined whether California walnut (Juglans L.