A field trial on the leaching and persistence of benomyl in an oil palm nursery agro ecosystem was conducted at Labu, Negeri Sembilan, Malaysia. Benomyl was analysed as its degradation product carbendazims because benomyl is a very unstable compound and easily degrades in organic solvents and aqueous solutions. Therefore, the quantification of benomyl was expressed as carbendazim. Experimental plots in the nursery were sprayed with the fungicide benomyl, while the control plot was left untreated. The fungicide was sprayed using a knapsack sprayer at the recommended manufacturer’s dosage as well as at double the recommended dosage. Composite soil samples were collected from each replicate plot at depths of
0-10 cm, 10-20 cm, 20-30 cm, 30-40 cm and 40-50 cm. Sampling of soils were taken at intervals of -1, 0, 1, 2, 3, 5, 7, 14, 30, 60 and 90 day/days after fungicide treatment. Analytical methods for the determination of carbendazim in soils were developed and good recoveries of over 80% with small standard deviations were obtained from soil samples. Carbendazim residues were detected until Day 1 after treatment. The carbendazim residues were found at a depth of 0-50 cm for both normal as well as double recommended dosages. The objective of this study was to evaluate the mobility and persistence of the fungicide benomyl in an oil palm nursery.