What horticultural practice involves removing crowded growth from a tree or shrub's crown?

Crown thinning is a horticultural practice specifically aimed at promoting a tree or shrub's health and aesthetic appeal by selectively removing crowded growth from its crown. This technique helps enhance light penetration and air circulation within the canopy, which can lead to improved growth and reduced risk of disease. It also maintains the tree's natural shape and structure while reducing the weight of the branches, thereby lessening the likelihood of branch failure.

In contrast, crown lifting involves raising the lower branches of a tree to create clear space beneath it, while crown reduction focuses on shortening the branches to decrease the overall height or spread of the tree. Crown clearing, although related, commonly refers to the removal of obstructions for public safety or clearance in a landscape setting, but does not specifically address the selective removal of crowded growth. Each of these practices serves a distinct purpose, but crown thinning is the method that directly pertains to managing crowded growth in the crown of a tree or shrub.