secondary cambium

• 次生形成层

secondary cambium的用法和样例：

例句

1. The vascular cambium is located between the xylem and the phloem.
   维管形成层位于木韧之间。
2. The base of scoin is cut diagonally to expose a large oval of cambium.
   接穗的基部被切成斜形，暴露出椭圆形的大圈形成层。