TY JOUR TI DIVERSITY OF SPRUCE SELECTIVE FORMS ACCORDING TO THEIR BARK IN PRIKAMYE KW coniferous-broadleaved (mixed) forests KW Permsky kray KW spruce stands KW selective forms KW drying in KW stability JO Vestnik of Kazan State Agrarian University AU Ivanchina, L.A. AU Zalesov, S.V. AU Kozhevnikov, A.P. PY 2019 IS 14 PB Kazan state agrarian University