Sixty-five soils were surveyed to determine the effect of soil properties on adsorption and phytotoxicity of 2-chloro-4,6-bis(ethylamino)-5-triazine (simazine). The ratio of simazine in solution to simazine adsorbed to soil was determined. The amount of simazine causing 50 % reduction in growth (GR50) of oats (Avena sativa L., var. Kanota) under controlled conditions was estimated by bioassay. Simazine adsorption by soils was an exponential function of the amount of simazine added. There was negligible correlation of GR 5 0 with pH and clay content. Percent silt and sand, although correlated to GR50, had little predictive value for dosage. There was a marked interrelationship between organic matter, cation exchange capacity, the equilibrium concentration of simazine in the soil solution, and GRgo. GRJJO was more closely correlated with percent organic matter than with any other factor. Dosage of simazine for plant response was largely predictable on the basis of organic matter alone. Simazine adsorption was largely predictable from cation exchange capacity and ratios of sand to clay. Activity of simazine was not governed by gross adsorption as measured in the experiment.

SUMMARY Granulation is a disorder of the Valencia orange in which the juice vesicles go through certain definite morphological and chemical changes. The larger the fruit, the more likely are granulated juice vesicles. The juice vesicles increase in volume with the subsequent hydration of the cell contents, followed by the gel formation of the pectic substances. The pectic substances and their respective methoxyl contents increased with the severity of granulation. The soluble carbohydrates and organic acids decreased as the mineral constituents and pH of the juice increased. The alcohol‐insoluble fraction of the juice vesicles increased with the severity of granulation, and a highly significant correlation existed between the hardness of the juice vesicles and the alcohol‐insoluble solids content.

A method for the determination of bromacil in agricultural soils and crops using gas-liquid chromatography with an electron-capture detector is described. Several complete analyses can be performed per day because of its simplicity. The specificity is good, with the sensitivity ranging from 0.01 p.p.m. for soil residues to 0.1 p.p.m. for crop residues.

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