Abstract
In order to clarify the root distribution and the pull-out resistance of six Quercus serrata Murray grown at the slope with 5～48°angle, we measured the number and diameter of roots > 1 mm in diameter at horizontal and vertical plates of soil profiles (n=4,483) , and performed the pull-out tests (n=640) . The relationships between root diameter and pull-out resistance differed the roots < 30 mm from the all roots (ANCOVA, p<0.05) . The number of horizontal roots was larger than that of vertical roots (paired t-test, p<0.001 or p<0.05) . The roots at the gentle slope grew to downward than upward and the diameter was larger at with gentle slope than that at the steep slope (GLMM, p<0.05) .
