Maize is a crop that is characterized by a high level of herbicide consumption, due to its efficiency and fastness of chemical control performance. Cultivation of maize is more profitable than cereals. The research conducted in 2004-2007 in western Poland on weed infestation in maize showed the negative aspect of maize cultivation in monoculture. At the beginning of the study, the following weed species occurred: Echinochloa crus galli, Chenopodium album, Agropyron repens, Galium aparine, Viola arvensis, Thlaspi arvense, Capsella bursa-pastoris, Anthemis arvensis and different dicotyledonous weeds present in field experiments. Four years later, the following taxons predominated in maize monoculture: Echinochloa crus-gali, Chenopodium album and new weed species which occurred in trials: Solanum nigrum, Aethusa cynapium. Therefore, experiments were performed in the Institute of Soil Science and Plant Cultivation in Wrocław (50^o58’ N; 16^o56’ E), using herbicides and the following mixtures: Lumax 537,5 SE – applied preemergence, Callisto 100 SC + Milagro 040 – applied postemergence at the 3-4 leaf stage of maize, Maister 310 WG + Actirob 842 EC + Mustang 306 SE – applied postemergence in split doses, limiting weed infestation in maize monoculture crop in direct sowing variant and simplified tillage variant, in ploughing cultivation. Long-term research showed that the effectiveness of herbicides present at farming market should be improved through, for example, postemergence herbicide choice to secondary weed infestation, and the application of mixtures of sulfonylurea herbicides used at the divided fractional doses for weed infestation control at postemergence time. The system of weed control using glyphosate to overwintering species and the ones germinating before a cultivated plant and additionally, the mixture of Maister 310 WG + Actirob 842 EC + Mustang 306 SE applied postemergence in split doses for the secondary weed control, made it possible to eliminate undesired plants on that soil stand in the most efficient way and to achieve the highest grain yield.

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