Quality and contamination of lawn mixtures in the forest-steppe of the Middle Volga Region

The aim of the study was to identify the effect of components (factor A) and their seeding rates in mixtures (factor B), the level of mineral nutrition (factor C) in the formation of lawn mixtures on weed infestation and their quality over the years of grass stand use in order to recommend the most effective of them for production. The experimental design included the following options: factor A – creeping clover + meadow bluegrass, creeping clover + perennial ryegrass, creeping clover + meadow fescue; factor B – 70 + 40 %, 55 + 55 %, 40 + 70 %; factor C – control (without fertilizers); P₄₅K₄₅; N₃₀P₄₅K₄₅. In the forest-steppe of the Middle Volga region, two experiments (in 2019 and 2020) were conducted on leached chernozem and a study of grass mixtures for 3 years of use (2020–2023). The lawn mixtures were mowed 4…5 times per season when they reached a height of 10…12 cm. In terms of weed infestation, the mixtures were rated at 1 point (slightly weedy) in the first and second years of use and 2 points (moderately weedy) in the third year. By the third year of use, the lowest number of annual weeds was noted in mixtures of creeping clover with meadow bluegrass – 10.1…19.0 pcs/m². With an increase in the fertilizer dose, the number of weeds decreased compared to the control – 10.1…22.8 pcs/m², in the control variants – 10.5–26.4 pcs/m². In the first year of using mixtures of creeping clover with meadow bluegrass and meadow fescue, the quality of the lawns was rated as «excellent». In the second year, fescue mixtures showed «good» and «excellent» ratings, while bluegrass and ryegrass mixtures mostly received «good» ratings, with some «satisfactory» variants. In the third year, clover-bluegrass mixtures showed the best characteristics: excellent density (6 points), high projective cover (5 points), complex rating – 30 points, which corresponds to the highest quality level.