Experiments were conducted from 1999 through 2001 in North Carolina to determine peanut response under weed-free conditions to applications of postemergence herbicides. In one set of experiments, peanut tolerance to acifluorfen plus bentazon or acifluorfen plus bentazon plus 2,4-DB applied alone or with diclosulam, dimethenamid, flumioxazin, or metolachlor 6 to 8 wk after peanut emergence was evaluated. In a second set of experiments, paraquat plus bentazon was applied alone or with diclosulam, dimethenamid, flumioxazin, imazethapyr, or metolachlor 2 wk after peanut emergence. In a third set of experiments, imazapic was applied alone or with diclosulam or flumioxazin 3 to 4 wk after peanut emergence. In the fourth experiment, 2,4-DB was applied approximately 7, 5, or 3 wk before digging and inversion of vines. Flumioxazin applied alone or with aciflurofen plus bentazon (with or without 2,4-DB) injured peanut more than diclosulam, dimethenamid, or metolachlor applied alone or with acifluorfen plus bentazon or aciflurofen plus bentazon plus 2,4-DB. Flumioxazin reduced pod yield 620 kg/ha when compared to non-treated peanut. Additionally, acifluorfen plus bentazon and acifluorfen plus bentazon plus 2,4-DB reduced yield by 200 and 150 kg/ha, respectively, when compared with non-treated peanut. Flumioxazin applied with paraquat plus bentazon was more injurious than diclosulam, dimethenamid, imazethapyr, or metolachlor applied with paraquat plus bentazon. There was no difference in peanut injury when paraquat plus bentazon was applied alone or with diclosulam. Dimethenamid or metolachlor increased injury by paraquat plus bentazon. Although diclosulam did not affect peanut injury from imazapic, injury increased when imazapic was applied with flumioxazin. When pooled over nine sites, 2,4-DB did not adversely affect pod yield, gross economic value, or percent seed germination when applied 7, 5, or 3 wk before vine inversion.

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