Herbicides provide a convenient means of weed control because of their effectiveness, low cost (relative to alternative strategies) and ease of application. 'Hyvar x'| and ~elpar'| weed killers are very effective broad spectrum herbicide treatments for general weed control in non-cropland amas such as forests, industrial and right-of-way weed control areas. However, residues at the application site and even some distance away via movement through soil layers can present an environmental problem. The active ingredient of 'Hyvar x'| is bromacil (5-bromo-3-sec-butyl6-methyl uracil) and is moderately soluble in water to 0.815 g/litre at 25~ (Worthing and Walker 1983). It is considered to be moderately to highly mobile (Rhodes et ai. 1970; Weber and Best 1972) and can persist in the soil up to 2 years in detectable amounts (Bovey et ai. 1967).