研究与生长关系密切的类型和质量性状,以及从苗期类型与性状表现预测其后生长作为选优的标准,具有重要意义。据南京林产工业学院调查,杉木浓密冠型的材积生长量比林分大50%,比稀疏冠型的大100%。以后不少单位相继证实这一情况,各地所选优树也大都为浓密型的,可见浓密冠型是个优良类型。因此,掌握苗期发枝习性和冠型的关系,对判断后期生长有一定意义。 Research and growth are closely related to the type and quality traits, as well as from the seedling type and trait performance prediction of subsequent growth as a criterion for selection, is of great significance. According to a survey conducted by Nanjing Institute of Forest Products and Technology, the volume of crown of Cunninghamia lanceolata is 50% larger than the stand volume and 100% larger than the sparse crown type. After many units have confirmed this situation in succession, the selected trees are mostly dense type, showing that crowded crown is a good type. Therefore, grasping the relationship between the seedling stage and the crown-type, to determine the late growth has some significance.