Soil from three depths was treated with (2,4‐dichlorophenoxy) acetic acid (2,4‐D) and 2‐chloro‐4‐(ethylamino)‐6‐(isopropylamino)‐s‐triazine (atrazine) and buried in the soil profile for 5, 17, 29 and 41 months at two locations in Nebraska. Degradation of 2,4‐D stored in field pits at 15‐, 40‐, and 90‐cm depths was rapid under aerobic soil conditions at both locations. Rates of atrazine degradation decreased with increasing soil depths. In Sharpsburg silty clay loam, phytotoxic amounts of atrazine dissipated during the first 5 months at the 15‐cm depth, and during the first 17 months at the 40‐cm depth. Atrazine treated samples buried at 90 cm in the same profile contained phytotoxic amounts of atrazine after 41 months as shown by a soybean bioassay and gas chromatographic analysis.