Last updated 2026-10-06 — Hopea hainanensis Hopea hainanensis is an evergreen tree, a Class I nationally protected plant. It has a straight trunk, typically growing over 30 meters tall, resembling a towering pillar. Its notable characteristics include: first, its wood is as hard as iron, earning it the title "steel of timber." Second, its density is greater than water, allowing it to sink. Third, it has a dense structure, clear grain, and is highly resistant to decay, soaking, and sun exposure. This naturally grown Hopea hainanensis is nearly extinct. In Bawangling, it can only be found sporadically, scattered across the Yajia Ridge. So far, more than 100 individuals have been discovered, with an average age of 120 years, an average height of 22 meters, and an average crown diameter of 28 meters.