Plots were established in 1970 in the Nebraska Sandhills for the control of green sagewort (Artemisia campestris L.). Herbicides were applied in 1970; 1970 and 1971; 1970, 1971, and 1972; and 1970 and 1972. Nitrogen fertilizer at 45 kg/ha was applied in 1973. Herbicide treatments included 2,4-D amine [(2,4-dichlorophenoxy)acetic acid], 2,4-D ester, 2,4,5-T [(2,4-5-trichlorophenoxy)acetic acid], silvex [2-(2,4,5-trichlorophenoxy)propionic acid], and mixtures of picloram (4-amino-3,5,6-trichloropicolinic acid) or dicamba (3,6-dichloro-o-anisic acid) and 2,4-D amine. Herbicides were most effective for the control of broadleaf weeds when they were applied in 3 consecutive years or in alternate years. Herbicides applied only once did not effectively control broadleaf weeds. When nitrogen was applied after weed control treatments, weed production increased if herbicide applications were not effective. If weed control treatments were effective, nitrogen did not affect weed production.