Acropetal differentiation of the cambium layer continues as the primary root elongates.

层向顶分化像初生根伸长一样在继续进行。

Interfascicular cambium A single layer of actively dividing cells between the vascular bundles in stems.

束层是于茎束具有旺盛分裂能力一层细胞。

Bark The outermost tissue of the stem and roots in woody plants, on the outside of the phellogen (cork cambium).

木本植物中茎或根中木栓层外方全部组织，称为树皮。