通过在黄龙桥北林区多年来的外业调查和生产实践,我发现油松树种在树形、树皮、枝、芽、花、叶、球果、木材、树脂等方面,有较大的变异。我初步将这些新变异划分为四种类型:柴松、黑粗厚皮汕松、红细薄皮油松和大果刺汕松。这四种变型油松在延安南部油松林区内均有单株或零星小片分布。其中以桥北林区的大麦店沟、松树沟、蒿芭寺、黄龙林区的官庄、红庙沟、蔡家川等山上较为明显。现分别介绍如下: Through the field investigation and production practice in Beilin district of Huanglongqiao for many years, I found that the species of Pinus tabulaeformis have great variation in the aspects of tree shape, bark, branches, buds, flowers, leaves, cones, woods and resins . I initially classified these new variations into four types: Chai Song, thick black skin pine, thin red skin pine and large pine thorn pine. The four types of Pinus tabulaeformis in southern Yan’an pine forest area are single or sporadic small pieces of distribution. Among them, the barley ditch, pine grove, Artemisia Temple in Qiaobeilin District, Guanzhuang in Huanglonglin District, Hongmiaogou Ditch and Caijiachuan Mountain are more obvious. Now introduced as follows: