Which term refers to a layer of bark located on the upper side of a branch at the branch union?

The term that refers to a layer of bark located on the upper side of a branch at the branch union is indeed the branch bark ridge. This area is a distinct ridge of bark that forms where a branch joins the trunk or another branch. It is an important feature for the health of a tree, as it helps protect the union from diseases and decay by facilitating the growth of the branch and ensuring that the union is properly sealed.

Understanding this term is crucial for landscape contractors and arborists, as recognizing the branch bark ridge can inform proper pruning practices. It is important to prune just outside this ridge to encourage healthy growth and minimize damage to the tree. Properly identifying this area can help prevent injury to the tree and support its overall vitality, which is an essential aspect of landscape maintenance.