Q: I need to know what the difference is between black gum compared to sweet gum, and how do I identify black gum. I think I am getting black gum in my sweet gum and our customers do not want it.

A: Sweetgum (Latin name Liquidambar styraciflua ) has white to light pink sapwood (sometimes sold as sap gum) and reddish brown to brown heartwood (sometimes sold as red gum).

Black gum (sometimes called tupelo gum) (Latin name Nyssa sylvatica ) has sapwood that is light gray brown and heartwood that is darker gray brown.

Positive separation of the wood (if the color does not provide obvious separation) can only be done with a microscope. Even with x10 magnification, they cannot be separated with certainty. I am curious what keys your customers are using to indicate they have black gum, as the experts cannot usually separate the two!