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The effect of nitrogen (N) doses on yield of the green maize ears and its production components was evaluated during two years. Five N doses (0, 60, 120, 180 and 240 kg ha-1) applied in topdressing were tested in a randomized block design with four replications. The efficiency of treatments was evaluated by the production and the number of commercial green ears per hectare, weight of husked and unhusked ears, length and diameter of unhusked ears and husked ear/husk ratio. Increases in husked commercial ear yield by N application were found, with maximum production of 13.52 t ha-1 estimated by 157 kg ha-1 N application (first year) and of 14,86 t ha-1 with 177 kg ha-1 N dose (second year). The increases in the production of green ears were not due to increases in the number of ears per area and by length of these. Differently of husked ear/husk ratio, the average weights of the husked and unhusked ears and diameter of unhusked ears were affected by N application. It was proposed a table of recommended N doses based on pre-establishedprices of N and commercial ears.

The experiment was carried out in an area of 8.4 ha of degraded Brachiaria decumbens pasture aiming to evaluate phytosociological parameters. The infestant flora assessment was made on six pasture areas before the establishment of crop-livestock system experiment, at 90, 210 and 330 days after implementation. The inventory square method was used for the phytosociological study, applied through a 0.5 m2 square frame thrown 35 times in each experimental plot. In order to evaluate the species present in the area, the following parameters were determined: frequency, density, abundance, relative frequency, relative density, relative abundance and value of importance of each species (IVI). In the survey accomplished in the pasture area before the experiment implementation, 18 species of 11 botanical families were identified. Poaceae (Gramineae) family presented the greatest number of species, followed by Leguminosae (Fabaceae) – Mimosoideae. At 90, 210 and 330 days after crop-livestock system establishment, 15, 19 and three species belonging to 11, 12 and three botanical families, respectively, were identified. On the maize plots for silage, in all evaluations, the most representative species found on the area was Brachiaria decumbens, with IVI over 100.