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The adsorption of 2,2',4,4,,5,5,-hexabromobiphenyl (HBB) by four Michigan soils conformed well to a Freundlich adsorption isotherm. Adsorption of HBB increased with increasing soil organic carbon (correlation, r = 0.87 to r = 0.96). Leaching studies using the same soils amended with 100 ppm of HBB showed that less than 0.6% of the HBB was lost from each soil with leachate quantities equivalent to 20 times the average annual rainfall in Michigan. Results suggest that PBB, which is present in some Michigan farm soils due to applications of PBB-contaminated manure, should not leach below the depth of incorporation.

Erwinia herbicola, Pseudomonas fluorescens, and P. putida were strongly attracted in vitro to substances exuded by conidia of Cochliobolus victoriae and sclerotia of Macrophomina phaseolina, but not to phosphate buffer solution. Numbers of bacteria attracted to propagules of C. victoriae or M. phaseolina in an unsterilized sandy loam soil were significantly (P = 0.05) greater than background populations occurring in soil saturated with buffer. Chemotactic response was greater to C. victoriae than to M. phaseolina both in vitro and in soil. Results suggest that living fungal propagules may act as attractants for motile bacteria in soil.