TFRI staff calculating the ages of illegally felled trees say that even "saplings" with trunks only 15 cm in diameter may in some cases be as much as 200 years old. The trees 'appearance belies their age, and the timber is much finer grained and denser than most of Taiwan's high-grade timber species.
林業試驗所人員曾計數被盜伐的紅豆杉年輪，僅十五公分直徑的「小樹」，就有兩百多歲，年輪肉眼難辨，材質比台灣大部分高級樹種都來的細密。