Influence of fertilization with nitrogen on selected oroperties of willow in the four-year cultivation cycle

This experiment was conducted to assess regrowth of shoots of willow in the four-years-cycle of cultivation at different doses of nitrogen. At length, thickness and number of shoots in the carp, were most affected by years of willow shoots regrowth, less by variety, doses of nitrogen and time of measurement. Among the interactions of those features big importance have interaction between varieties and years of regrowth of shoots, between varieties and doses of nitrogen and years of regrowth of shoots and doses of nitrogen. The average of ten varieties of willow, longest and thickest stems were obtained at doses of 180 kg of nitrogen per hectare. Tested varieties of willow were characterized by different reactions to the doses of nitrogen in the analyzed features. The varieties 1047, Oloff and 1047D had the longest shoots and varieties Start and Ekotur - thickest shoots at the doses of 180 kg of nitrogen per hectare. Doses of 180 kg.ha(-1) reduced numbers of stems per carp