That scar is an artifact of a process called grafting, or fusing two separate pieces of wood into a new tree. From citrus to peaches, almost all fruit trees are grafted, and so are pecans.

While familiarity with the term “grafting” is widespread among gardeners, a true understanding of what grafting is and why it is done is not so common. In a nutshell, grafting is a ...

Many grapevines are propagated by grafting a branch from an existing vine onto rootstock, which allows the grower to selectively reproduce desirable traits in the grapes, she explained.