Oxadiazon is a broad-spectrum preemergent herbicide that is moved off the foliage and into the soil by a sprinkler irrigation following application. Oxadiazon is a shoot-girdling herbicide. Used during the growing season from spring until fall. Granular oxadiazon is safe on most woody plants. The wettable powder formulation is generally not used in nursery stock. In containers, granular oxadiazon plus napropamide is a good combination, with a broad range of safety in woody plants. Oxadiazon plus napropamide often has an improved margin of safety over Rout or OHII, especially in young, actively growing plants. Oxadiazon does not control weeds in the chickweed family but napropamide controls those. Has a relatively long residual, 12-16 weeks. Oxadiazon is not very effective on certain broadleaves including pearlwort, chickweed, and horseweed. Re-treatments are required at about 3- to 4-month intervals to maintain control throughout the season. Oxadiazon is very effective when applied in fall or spring.
Oxadiazon does not leach readily in the soil, is not a root inhibitor, and thus is less likely to injure established species. Injury may occur, however, if oxadiazon is applied to wet foliage, is not washed from the foliage, or the granules collect in leaf bases or crowns. If treated soil is cultivated, weed control effectiveness is reduced. Oxadiazon has very low solubility in water: 0.7 mg/L (Merck & Co 1996). Its mobility (as Koc) is 3200, which indicates that it is strongly adsorbed to organic soil, and therefore unlikely to be highly mobile in organic soils.
Molecular formula: C15H18O3N2Cl2
Molecular weight: 345.23
Specifications: 95% TC, 93% TC, 38% SC