At the harvesting time of Wheat, soil surface sample in July 2005 contained residues of propiconazole {1-[[2-(2,4-dichlorphenyl)-4-Pr-1,3-dioxolan-2-yl]methyl]-1H-1, 2,4-triazole; Tilt}. Propiconazole is a fungicide that is applied to wheat at later growth stages against upper leaf and seed diseases (Stadnik and Buchenauer 1999; Goulart and Paiva 1993). Propiconazole is less mobile and highly adsorbed to agricultural soils (Thorstensen et al. 2001). Low soil water content, that has been experienced in Corvallis during June and July 2005, was an important factor that might have increased soil sorption of propiconazole and influenced its microbial degradation (Roy et al. 2000).