2013 Volume 58 Issue 4 Pages 215-220
The effect of cattle grazing on dynamics of tree seedling recruited into Akkamori, Kitakami-sanchi hills and mountains, northern Japan was investigated in order to manage trees in semi-natural grassland. The number, survival rate and height of the seedlings of the dominant three species [Betula ermanii Cham. (54%, the proportion to total numbers), Acer mono Maxim. (25%) and Acer japonicum Thumb. (11%)] were compared in grazed and ungrazed plots from 2003 to 2010. Seven to fifteen Japanese Shorthorn were grazed from June to September on 16.6 ha of semi-natural grassland [8.7 ha of grassland (dominated by Carex spp. and Zoysia japonica Steud.), 5.5 ha of forest (dominated by B. ermanii with many gaps dominated by Z. japonica), and 2.4 ha of scree]. Contrary to Acer spp., the seedling density of B. ermanhi was higher in grazed plots than in ungrazed plots. Both survival rate and height growth of seedlings of three species were lower in grazed plots than in ungrazed plots. In grazed plots, the survival rate of seedlings of B. ermanii, A. mono and A. japonicum became 0% in five, four and three years, respectively. These results demonstrated that cattle grazing prevented establishment of tree seedlings in the semi-natural grassland.
