Formation of lawns from grass varieties of Danish and Dutch selection in the Moscow region.

The study was carried out at the Field Experimental Station of the Russian State Agrarian University -- Moscow Timiryazev Agricultural Academy (Moscow, Russia) in two field experiments. In experiment 1 from 2017 to 2019, the authors studied the reaction of lawn grasses of the Dutch selection type to the operational load on the sod (trampling). Perennial ryegrass, red fescue, Kentucky bluegrass, and a three-component herbal mixture from these grass types were exposed to a low, medium, and high degree of operational load. In experiment 2 from 2003 to 2014, the authors investigated the resistance of Danish selection grasses in two- and four-component grass mixtures. In experiment 1, in the second year of life, single-species crops of perennial ryegrass, red fescue, and a three-component grass mixture formed dense grass stands with the number of shoots from 129 to 183 pcs/dm2. Kentucky bluegrass showed significantly inferior results, with the density of herbage not exceeding 53-66 pcs/dm2. In the third year of life, due to the lack of atmospheric precipitation, the density of all herbage, except for meadow bluegrass, decreased by a factor of 2.0-2.4. In 2017 (the first year of herbage life), the number of wild grasses was insignificant, amounting to 0.6-0.8 pcs/m2. In 2018, weediness increased to 3.3-5.6 pcs/m2 and in 2019, up to 6.1-9.5 pcs/m2. Lawn-type grasses had a low yield level, with the dry weight from 1.5 to 3.5 t/ha. On average, over 2 years, the grass mixture formed 45.1% more aboveground mass than single-species grass crops. In experiment 2, during the long-term operation of lawns from grasses of Danish selection, red fescue was the most stable in the composition of herbage. In the twelfth year of the life of grasses, its proportion ranged from 46.7 to 88.6%. The least long-lived species was the creeping bent, which dropped out of the agrophytocenosis in the eighth year of life. [ABSTRACT FROM AUTHOR]