Zalom, F.G., Werner, I., Oliver, M.N., Deanovic, L.A., Kimball, T., Wilson, B.W., Henderson, J.D., & Wallender, W.W. 2004 Organophosphate dormant spray pest control efficacy, pesticide concentration and toxicity in storm runoff.. Bulletin of Environmental Contamination and Toxicology 73(2): 299-305.

Notes: The effects of adjusting organophosphate (OP) dormant spray application timing on pest control efficacy and toxicity of stormwater runoff were examined in almond orchards near Waterford (2001 and 2002) and Cortez (2001), and in a French prune orchard near Sutter (2002) in California, USA. Early, middle and late treatments were given and runoff samples examined for diazinon concentrations. Results supported our hypothesis that OP concentrations are reduced when time between diazinon application and major storm events is increased. Economically, acceptable control of San Jose scale Quadraspidiotus perniciosus [Diaspidiotus perniciosus] and peach twig borer Anarsia lineatella, two of the major target pests of dormant season OP sprays, was achieved at earlier diazinon or chlorpyrifos application dates.