A scar left behind after the dropping of a northern Catalpa leaf (Catalpa speciosa). The letting go is controlled by chemistry in the tiny abscission zone, a narrow band of cells at the base of ...

The two methods are: (1) by leaf prong count and (2) by rhizome leaf scar count at the root neck. Leaf prong count method: Ginseng plants can have from one to as many as four palmately compound ...

At the point where the stem of the leaf is attached to the tree, a special layer of cells develops and gradually severs the tissues that support the leaf. At the same time, the tree seals the cut, so ...