Traditionally only the darkest heartwood—about 10% of each tree—is harvested for instruments.

传统上，仅采伐颜色最深的心材（每棵树的约 10%）来制作乐器。

But when the people of those forests found the infected trees, deep in the heartwood was a kind of wood inside a tree that was richly dark in color.

但当那些森林里的居民发现受感染的树木，发现在树的心材深处，有一种颜色深沉浓郁的木材。

And when a log gets to the sawmill, they're going to basically separate those two things because there's different uses for sapwood and for heartwood.

当原木运到锯木厂，基本上将边材和心材开处理，因为边材和心材各有不同的用途。

So you want to cut the sapwood from the heartwood because the heartwood is extraordinarily strong and you use it for

因此，你希望将边材从心材出来，因为心材异常坚固，适合用于需要承受重压的柱子、横梁和类似结构。

The third most highly prized of all these precious trees and their heartwoods was the Lao Wo Da Hong Suan Zhi.

这些珍贵树木及其心材，排名第三的是老挝大红酸枝。

Your heartwood is gonna be older, obviously, because you know how you can tell a tree by the rings, those inner rings that we talked about, the xylem.

显然，心材显得更老，这是显而易见的， 因为你了解通过年轮来判断一棵树的年龄，就是我之前讨论过的那些内部年轮，即木质部。 对吧，当形成层不断生成更多的木质部细胞， 它位于心材的外部。

Further inside, deeper into the tree, that's the older xylem, and that's the heartwood.

更深处，深入树干内部，那是较老的木质部，也就是心材。

Right, and as the cambium is creating more xylem cells, they're going on the outside of the heartwood.

是的， 随着形成层不断产生更多的木质部细胞，这些细胞布在心材的外部。

And there's gonna be more knots in that heartwood, too, from branches past.

那心材也因过去的枝条而形成更多节疤。