The structure of the weed and seed productivity of weeds in plantings of willow energy the first year of life. It is established that the greatest number of weed species are presented in families of grass: Graminеае, Chenopodiaceae, Polygonaceae, Solanaceae, Rubiaceae.

Black poplar (Populus nigra L.) is fast-growing species, demanding in terms of light and soil and very sensitive to weeds, especially in the first vegetation. Therefore, developing effective, environmentally friendly weed control measures is an urgent task for herbologists. There is an inverse relationship between the amount of weed mass and the productivity of black poplar; the lowest height, biomass yield and energy yield (87.1 cm, 0.41 t/ha and 8.06 GJ/ha, respectively) were found in the control treatment with the highest weed mass accumulation (3062 g/m 2). The practice of mechanical weed control influenced the accumulation of weed mass in the black poplar plantations. Three consecutive cultivations of interrow space and three consecutive harrowing sessions at an interval of 14 days reduced weed mass 2.7 times. Soil mulching with sawdust almost completely destroyed the weeds in the experimental plots.