Because in the past the yew lacked economic value, it was not replaced by artificial replanting after logging, so that with the numbers of its wild population declining, it now gained an extra rarity value.
過去缺乏經濟價值，砍伐後未被更新、再造人工植群，天然數量又日愈匱乏，造成物以稀為貴，更為它帶來了高附加價值。