Shiwandashan Nature Reserve is located between Fangcheng and Shangsi counties (cities), Banba in Fangcheng, Long Fu, Suo Na and Naqin, Shiwandashan National Forest Park and Pingjiang Farm in Shangsi, and the existing narrow leaf slopes still exist. Mainly distributed in valleys, streams or evergreen broad-leaved forests below 600 meters above sea level. Occasionally, it grows in the well-preserved "Feng Shui Forest" on the edge of the village, which is distributed in small pieces or sporadically, but it is not distributed in the upper part of the hillside or in the severely damaged barren hills and wasteland. Narrow leaf slope is relatively concentrated between Shiwandashan National Forest Park and Fangcheng Long Fu Township, and other distribution points are scattered and few in number. The communities distributed on narrow leaf slopes are mostly secondary forests restored after human destruction, with a community height of about 10m and a canopy density of over 0.9. The appearance is evergreen, which can be divided into tree layer, shrub layer and herb layer, but the stratification is not obvious. The species composition of the community is rich, the floristic composition is complex and the tropicality is obvious. Narrow-leaved slope is one of the dominant tree species in some communities, which often forms the upper tree species of the community with wood snail, phoenix tree, mountain alum and Leipa line stone. Shrubs under the forest grow luxuriantly, mostly tree seedlings. In addition, there are real shrubs, such as nine-section grass, myrtle, wild peony and so on. Herbs are sparsely distributed, with few species, and most of them are ferns that like humidity.
Guangxi (100,000 Dashan, Longzhou Daqingshan). The model specimens were collected from Shiwan Mountain in Guangxi.