Why might trees be pruned?

Pruning trees serves several purposes, and one significant reason is to increase the amount of clear wood in saw-timber trees. This is achieved by selectively removing branches that can hinder the growth of a straight trunk and lead to knots in the wood. As the tree grows, these knots can detract from the quality of the lumber, reducing its market value. By pruning, foresters can encourage the development of a sound, clear trunk that results in higher-quality timber when harvested.

The other options, while related to tree management, do not directly address the primary objective of pruning in the context of timber production. For instance, improving soil quality is typically associated with practices like mulching or adding organic matter rather than pruning. Encouraging more tree growth is not a primary goal of pruning; while it may happen as a side effect, the focus of pruning is more about shaping the tree for optimal future growth factors. Reducing the number of trees would apply to thinning processes rather than pruning, which specifically involves cutting back branches within the same tree rather than removing entire trees.