Mobility of aniline, benzoic acid, and toluene in four soils and correlation with soil properties.

Soil properties and retention mechanisms affecting the relative mobility of aniline, benzoic acid, and toluene in Cecil sandy loam (clayey, kaolinitic, thermic Typic Hapludults), Holdredge silt loam (fine-silty, mixed, mesic Typic Argiustolls), Sharpsburg silty clay loam (fine, montmorillonitic, mesic Typic Argiudolls), and Valentine fine sand (mixed, mesic Typic Ustipsamments) were delineated in laboratory studies. The effect of the synthetic organic compounds (SOCs) was also determined on effective organic campounds (SOCs) was also determined on effective cation exchange capacity (ECEC) of the soils. Benzoic acid was most mobile of the SOCs but was retained in the Cecil soil by hydrogen bonds to Fe oxides. Toluene was least mobile and probably was hydrophobically sorbed to all soils. Aniline was electrostatically retained in protonated form to organic and inorganic exchange sites of the soils and reduced the ECEC of aniline-treated Holdredge and Sharpsburg soils.

Dispersion, Dissipation, and Efficacy of Methyl Bromide-Chloropicrin Gas vs. Gel Formulations on Nematodes and Weeds in Tifton Sandy Loam.

Dispersion, dissipation, and efficacy of gas and gel formulations of methyl bromidechloropicrin (202, 269, 336, and 403 kg/ha) on nematodes and weeds on tomato were studied in field plots. Concentrations of methyl bromide and chloropicrin 4 hr after soil treatment were greater at a depth of 15 cm than at 30, 45, or 60 cm. The concentrations of both chemicals decreased with lower doses, greater depths, and longer times after application. The gel formulation was more persistent than the gas formulation at both 336 and 403 kg/ha at depths of 30 and 45 cm, especially 24 and 36 hr after chemical application. Plant growth and yield were improved when nematodes and weeds were controlled.