一、形态特征常绿大乔木,高可达30—40米,胸径可达1.5米。树冠伞形,主干通直圆满,侧枝对生,平展,先端下垂。幼树树皮灰白色光滑,具多数大型皮孔,大树皮灰褐色、黑褐色,表面有小薄片皮脱落。小枝四棱形,赤红色,具明显皮孔。单叶对生,在枝上排成二列;叶大,长卵形或长方状椭圆形,长10—20厘米,幼树叶可长逾30厘米,先端急尖或长尾尖,基部心形,叶柄很短。顶生圆锥花序,花白色,直径可 First, the morphological characteristics evergreen tree, up to 30-40 meters, diameter up to 1.5 meters. Canopy umbrella, the trunk straight round perfect, collateral pairs, flat, apex drooping. Saplings bark gray and white smooth, with the majority of large leather holes, large bark brown, dark brown, the surface of a small sheet of peel off. Branchlets four prism, reddish, with obvious lenticels. Leaves simple, oblong or oblong-ovate, 10-20 cm long, young leaves longer than 30 cm, apex acute or long tail, base of the heart Shaped, petiole short. Top panicles, flowers white, diameter can be