We surveyed a stand of patchwork-like mixed planting 30 years after its planting, and discussed whether this method is useful for the creation of mixed forests. In each patch 25 trees of the same species were planted in 5 rows by 5 columns. There were 3 plots with planting densities of 5,000, 10,000, and 40,000/ha. The sizes of patches were 7.0 by 7.0 m square, 5.0 by 5.0 m, and 2.5 by 2.5 m, respectively. Nine species of hardwoods were planted. Average heights of
Betula platyphylla var.
japonica were the highest, followed by
B. maximowicziana,
Prunus sargentii,
Kalopanax pictus,
Cercidiphyllum japonicum,
Quercus crispula,
Tilia japonica,
Maackia amurensis var.
buergeri, and
Phellodendron amurense. All patches of birches,
K. pictus, and
C. japonicum survived, but some patches of
P. sargentii,
M. amurensis var.
buergeri,
Q. crispula, and
T. japonica, in either the 10,000 or 40,000/ha plot, and all patches of
P. amurense in all plots disappeared. Crown canopies above patches of birches consisted of those of trees planted in the plots. Crowns of birches intruded into patches of other species with slower initial growth. Although patchwork-like mixed planting is effective for creation of mixed forests, some improvement is necessary to allow all patches to survive; either making patches bigger than 49 m
2 or creating strips of un-planted areas between patches needs to be tested.
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