一、主要形态特征大乔木,成龄树可高达12米以上,枝下高一般为1～1.7米,胸径可达30厘米以上,一般为20厘米左右,平均年生长量为1厘米以上,树冠倒卵形,分枝近轮状,树皮灰白,纵裂,裂纹红色,新梢灰白色,密被绒毛,每叶具小叶9～15枚,以13枚为多,小叶长椭圆形,先端尖,长6～13厘米,宽8～5厘米,顶小叶长宽比为1.9:1,复叶柄 First, the main morphological characteristics of large trees, mature trees can be as high as 12 meters above the branches are generally 1 to 1.7 meters high, breast diameter up to 30 cm or more, usually about 20 cm, the average annual growth of 1 cm or more, the crown Ovate, branches nearly whorl, bark gray, longitudinal crack, red crack, shrill white, densely tomentose, leaflet 9 ~ 15 per leaf, with 13 as much, leaflets oblong, apex pointed, long 6 ~ 13 cm, width 8 ~ 5 cm, the ratio of top leaflet 1.9: 1, complex petiole