Abstract: | The distribution resulting from the drenching of soil with a suspension concentrate of 14C]metazoxolon was studied in the laboratory and the field. Penetration of soil columns was increased by (a) increasing the drench volume from 1 to 7.8 litres m?2, (b) changing the original soil moisture content from air-dry to field-capacity, and (c) including 1 % of ‘Renex 30’ surfactant in the drench. Penetration was greatest in soils containing large pores and was reduced when aggregates were broken down by sieving. Leaching the column with 1.56 cm of ‘rain’, 15 h after treatment, did not increase the penetration by metazoxolon. In all experiments, the maximum concentration of metazoxolon occurred in the top 2 cm of soil. Equivalent effects were found when metazoxolon was applied to a poorly-structured sandy clay loam in the field. |