Effect of nitrogen fertilization and fluroxypyr (starane 250 EC) herbicide on the Share of grass and common dandelion in meadow sward

The aim of the three-year experiment was to evaluate the action of Starane 250 EC herbicide and different levels of nitrogen fertilization on the share of grass and amount in the meadow sward of common dandelion. The field experiment was established on a permanent meadow in April 2007 in Żelków in the system of randomized subblocks with three replications.\ud In the experiment two research factors were used. The first factor was varied fertilization (34% ammonium nitrate) applied in an amount of: A1 – 0 kg·ha-1, A2 – 90 kg·ha-1, A3 – 180 kg·ha-1 and A4 – 270 kg·ha-1. Another research factor was Starane 250 EC herbicide, applied at four doses: B1 – control, B2 – 0.6 l·ha-1, B3 – 1.2 l·ha-1, B4 – 1.8 l·ha-1. The results were evaluated statistically by using analysis of variance for two-factor experiments. Mean differentiation was verified by Tukey’s test at significance level of p ≤ 0.05. In this study the impact of increasing doses of nitrogen and herbicide Starane 250 EC concentration on participation of grasses in the sward was established, while a greater impact of the used herbicide was observed. The favourable floristic composition of sward was observed after application of 1.8 l·ha-1 herbicide Starane 250 EC and 180 kg·ha-1 nitrogen