That scar is an artifact of a process called grafting, or fusing two separate pieces of wood into a new tree. From citrus to ...

So which trees are best for firewood, and which should be avoided ... On the other end of the spectrum, if hickory, pecan, mulberry, bur oak, or red oak can be located, these would all produce ...

pecan groves that seemed to stretch into infinity. Without compunction they chopped the trees down to grow cotton and turned the fine, hard timber into ax handles, wagon parts, and firewood.

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.