The Influence of Grass Stand Composition on the Yielding Capacity of Pasture Phytocenosis in Conditions of North-Western Russia
The results of the four-year long research (2012-2015) are presented in the course of which the influence of legume and cereal grasses on the yielding capacity, feeding value and botanical composition of pasture phytocenosis were defined. The research was carried out on the derno-podzolic light loamy medium cultivated soil with 2,17% of humus, 197 mg/kg of labile phosphorus, 150 mg/kg of exchangeable potassium and pH<sub>sol</sub> - 5,2. The scheme of the experiment included 7 variants, repeated three times, the area of the representative plot was 11 m<sup>2</sup>. The system of soil cultivation was generally acceptable for the region. In the first variant of the experiment mineral fertilizers were not applied under cereal grass stand. In the second variant nitrogen was applied in two stages: in spring - N<sub>60</sub> and after the second cycle of use - N<sub>60</sub>. In variants 3-7 the fertilizers in the doze P<sub>60</sub>K<sub>90</sub> were applied in spring at the beginning of vegetation. Crass mixtures including timothy of the sort Vologodskaya local, fescue of the sort Sverdlovskaya 37, goat's-rue eastern of the sort Krivich, vetch of the sort Sunny, red clover of the sort Karmin were studied. By applying nitrogenous fertilizers in the doze 120 kg/ha cereal grass stand provided substantial gain to the control 2,3 t/ha of dry mass, high outcome of changeable energy 52,5 GJ/ha, the amount of feeding units 4134 and digestible protein 659,9 kg per ha. By productive indices among legume - cereal grass stands the grass mixture was marked, that included two types of cereals-fescue and timothy and two types of legumes - goat's-rue and red clover, providing yield gain to the control of 0,6 t/ha of dry mass, gathering from 1 ha 2851 feeding units, 400,6 kg of digestible protein and the outcome of changeable energy of 35,8 GJ.