What does topping refer to in tree maintenance?

Topping refers to the practice of drastically cutting back on the upper branches of a tree, often without considering the health of the tree. This method can be harmful because it removes a substantial portion of the tree's foliage, which is essential for photosynthesis and can lead to issues like increased vulnerability to pests and diseases, as well as improper healing of the cuts. Topping is often mistakenly seen as a way to control tree size or shape, but it can lead to more growth issues down the line, as the tree may respond by sending out numerous weakly attached shoots.

The other options do not accurately describe what topping entails. For example, increasing tree size through fertilization is a healthy method of growth management, while shaping the tree encourages proper growth habits and health. Planting new trees around existing ones pertains to landscape planning rather than maintenance of an existing tree.