Abstract:
The research was carried out on the waterlogged marginal lands in the zone of unstable moisture of the Central Forest-Steppe of Ukraine. The generalization of the dynamics of changes
in the number of weeds in the miscanthus plantations of the first year of growing allows to divide
the growing season into three specific periods. The dynamics of weed infestation in Miscanthus x giganteus J.M. Greef et Deuter ex Hodk. et Renvoize plantations of the first and subsequent years of growing, monthly accumulation of weed green mass starting from 10
th
June was studied. The number of weeds in the plantations of miscanthus increased most intensively in the period from
the middle of May to early June. In subsequent periods, with the achievement of full projective
coverage of the field by plants, the intensity of new weed seedlings' appearance decreased. The most abundant weed species were Echinochloa crus-galli (L.)P. Beauv., Setaria glauca (L.) P.Beauv., Thlaspi arvense L., Sinapis arvensis L., Sonchus arvensis L., and Chenopodium album L. All considered
herbicides showed the highest level of toxic action to the seedlings of annual cereal weed species. Seedlings of perennials Sonchus arvensis L., Cirsium arvense (L.) Scop. have not been affected by soil
herbicides. The following herbicides: Master Power OD at an application rate of 1.5 l/ha
(efficiency 95.0%) or Milagro 040 SC at an application rate of 1.25 l/ha (efficiency 88.0%.) are
recommended during the season of plant vegetation.