1. 386 native dawn redwood trees were disappeared from census of 1983 of 5, 779 to 5, 393 in 2003.The metasequoia population which is in serious lacking of saplings and seedlings cannot regenerate naturally.
1983年左右的水杉普查结果显示原生水杉母树有5779株，2003统计有5393株，20年内减少了386株。水杉原生种群中没有幼苗和幼树，自然更新不良，呈衰退的趋势。
2. Dawn Redwood (Metasequoia glyptostroboides), a living fossil, is an important endangered plant species with a limited distribution around the borders of Hubei Province, Hunan Province and Chongqing Municipality in China.
活化石水杉是重要的珍稀濒危植物，天然水杉只分布于我国湖北、湖南和重庆三省市交界的一小片区域，总数量只有4000多株。