A constant transitional zone exists
between the altitude strips of forests with absolute prevalence of P. ajanensis
and P. koraiensis. In said zone, these species form unique mixed forests
that in the system of forest classification correspond to a subformation.
Initially, an admixture of P. koraiensis increases in the lower part of the alpine zone with P. ajanensis and A. nephrolepis. With decrease in the absolute altitude of the locality, these species become codominants, and then the share of Picea gradually decreases with resultant transition to typical cedar forests.
The position of cedar in this transitional zone is to some measure unstable, since during its cuttings the PiceaЧAbies canopy close up to prevent the growth of existing cedar and appearance of its subsequent seedlings. With complete cuttings of all coniferous species, even with preservation of seedlings present under the chopped tree stock canopy, cedar does not grow as rapidly as do other species, and its significant part dies off. Cedar growth is especially suppressed by Abies nephrolepis, which grows quicker. In these conditions, to preserve the role of cedar, there would be need for intense cutting and care to free it from oppression by all species, notably A. nephrolepis.