treering

例句：

1. 1. The treerings in the forest tell a story of the past.
   森林中的树皮层讲述了过去的故事。
2. 2.The treerings are an important indicator of the age of the tree.
   树皮层是判断树木年龄的重要指标。
3. 3.The treerings were analyzed to determine the cause of the tree's decline.
   对树皮层进行分析以确定树木衰退的原因。