TY JOUR TI CREATION OF LONG-TERM HAY AGROCENOSES SUSTAINABLE IN PRODUCTIVITY IN THE TVER REGION CONDITIONS KW drained lands KW agrophytocenoses KW clover-alfalfa-timothy mixture KW clover-alfalfa-fescue mixture KW dry mass yield KW mineral fertilizers JO Bulletin of KSAU AU Pavlyuchik, E.N. AU Kapsamun, A.D. AU Ivanova, N.N. PY 2025 IS 0 PB Krasnoyarsk State Agrarian University