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西南桦是热带山地、南亚热带地区的速生珍贵树种，作为热区人工造林的一个主要树种有着重要的意义。其天然分布最为密集的地区是云南西南部、南部、东南部，广西西部、西南部，也是西南桦的现代分布中心。西南桦人工林群落的种类组成仍与其造林前的成分大致相同，以热带成分为主，其分布区类型以热带属占主要地位。群落的水平结构是存在度Ⅰ占多数，为５２．５２％ ，而存在度Ⅴ仅为６．０６％ ，反映出热带山地雨林的特征。垂直结构简单，乔木层即西南桦一层。下层植被发达。生活型结构特征为中大乔木占８．１％ ，小乔木占５．３％ ，灌木占２２．２％ ，草本占１８．２％ ，藤本植物占２６．３％ 。
Southwest birch is a tropical mountainous, subtropical fast growing rare species, as a hot zone afforestation of a major species of great significance. Its natural distribution is the most intensive areas in southwestern Yunnan, southern and southeastern Guangxi, western and southwestern China, but also the modern distribution center of Betula alnus. The species composition of the Betula alnoides plantation community is still roughly the same as its pre-afforestation composition, with the tropical components as the dominant species, and the distribution type is dominated by the tropical genus. The horizontal structure of the community is the existence of the majority I, accounting for 52.52%, while the existence of only Ⅴ 6.06%, reflecting the characteristics of tropical mountain rainforest. Vertical structure is simple, arbor layer that is a layer of Betula australis. The lower vegetation developed. The life-form structure is characterized by 8.1% of middle-large trees, 5.3% of small trees, 22.2% of shrubs, 18.2% of herbs and 26.3% of vines.