This research investigates the efficiency of trifluralin incorporation in soils using four different equipments, such as, disk harrow, rotary plow, flexible spiketooth harrow and rotary hoe, during 1978/1979 and 1979/1980, at Campinas, State of São Paulo, Brazil, in cotton fields. Laboratory tests were also carried out to verify the depth of the herbicide action using soil samples collected through special cylinders with known diameter and height and sowing seeds of check plants. Rotary plow showed the best results. In regarding to the disk harrow, normally used to incorporate trifluralin, double harrowing at different depths is suggested as a good practice, superposing up to half harrowing width in the second pass.
agricultural mechanization; agricultural machinery; herbicide applicators; performance of agricultural machines; field tests