Field experiments were carried out in 2008 and 2009 to develop an efficacious and cost-effective weed control program for maize. Herbicides containing terbuthylazine (Click 500 SC), nicosulfuron (Accent 75 WG) and tritosulfuron + dicamba (Mocarz 75 WG) were applied in tank-mixtures at reduced rates, sequentially at 14- to 18-day intervals with nonionic surfactant Trend 90 EC or methyleted seed oil adjuvant Atpolan Bio 80 EC. These standard herbicides were also applied once at recommended timing and rates, without adjuvant. Maize was infested mostly with Chenopodium album L., Polygonum convolvulus (L.).Á Löve and Echinochloa crus-galli (L.) P. Beauv. Broadleaf plus grass weed control with standard herbicide treatment of Click 500 SC, Accent 75 WG and Mocarz 75 WG was only 28, 6 and 21%, respectively. Herbicide tank-mixtures applied sequentially at reduced rates with adjuvants greatly increased weed control and weed control consistency that ranged between 92 and 99%. Atpolan Bio 80 EC was more effective adjuvant then Trend 90 EC. Sequential application of herbicide mixtures with adjuvants provided high increase of maize grain yield (as compared with the control by 9.36-10.38 t·ha^-1) and high net return (from 4037 to 4482 PLN·ha^-1). Benefits from standard herbicide treatments applied once at recommended rates without adjuvant were significantly lower (grain yield increase by 0.49-2.60 t·ha^-1 and net return from -6 to1080 PLN·ha^-1).

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