What type of trees are characterized by having a branching pattern that grows outward and is more rounded?

Decurrent trees are characterized by a branching pattern that grows outward and develops a more rounded shape as they mature. This growth pattern is typically seen in species that spread their branches horizontally, creating a broad canopy. The result is often a more rounded and fuller appearance, which can provide extensive shade and is often desirable in landscape settings.

In contrast, excurrent trees tend to have a more vertical growth habit with a central leader and branches that ascend, giving them a conical or pyramidal shape rather than a rounded one. Columnar trees, as the name suggests, grow in a narrow and upright manner, which does not fit the description of the outward, rounded branching pattern. Pyramidal trees typically exhibit a triangular shape as they grow, maintaining a central leader, which again contrasts with the rounded, outward branching of decurrent trees. Understanding the distinctions among these forms helps in selecting the right trees for specific landscaping and ecological purposes.