Features of growth and development of alfalfa-cereal grass stands depending on the species composition and fertiliser

The results of studies on the influence of the species composition of herbage, the level of fertiliser, and growth stimulator Fumar on the density and botanical composition of plants are presented. The experimental part of the study was performed in the scientific laboratories of the Department of feed production, land reclamation and meteorology in the production division of the National University of Life and Environmental Sciences of Ukraine "Agronomic Research Station". The territory of the station is located in the Right-Bank Forest-Steppe and is part of the Bilotserkivsky agro-soil district. Experimental plots were laid on chernozems of typical low-humus large-dusty light loamy mechanical composition, which are characterised by a high content of nutrients. The climate of the region is characterised by unstable humidity and moderate temperature conditions. The average annual air temperature is 6-8°C. The annual amount of precipitation reaches 562 mm, during the growing season – 354-394 mm (63-70% of the annual norm), which falls unevenly throughout the year. Based on the conducted studies, it was identified that sown herbage is formed with a density of 686-1250 shoots per 1 m2 and a height of 58-148 сm. Alfalfa-cereal and cereal stands are denser than alfalfa ones. For the period from 1 to 3 years of use of herbage, the density of alfalfa shoots decreases, while that of orchard grass and smooth brome increases, and more intensively with the introduction of N60. During the first three years of use, grass stands are formed with the dominance of sown components with a share of alfalfa in single-species sowing of 85-98%, in alfalfa – cereal mixtures – 30-58%. For the period from the 1st to the 3rd year of use of alfalfa-cereal stands, the share of alfalfa decreases by 11-24%, and more intensively with the introduction of N60. In addition, between the two cereal components, there is a change of co-dominant – from meadow fescue to eastern fescue, eastern fescue to orchard grass, perennial ryegrass to smooth brome, like in the cereal stand, eastern fescue to smooth brome. In the 3rd year of use, ryegrass thins out, reducing the involvement rate to 5-14%