What type of branching includes palm trees with a single unbranched stem?

The branching pattern described, exemplified by palm trees with a single unbranched stem, is accurately identified as columnar. This type of growth results in a tall, straight trunk that produces leaves only at the top, while the lower part remains free of offshoots or branches. This structural form allows the plant to reach significant heights and is particularly advantageous in environments where they compete for sunlight.

In contrast, deliquescent branching typically involves a tree structure with a trunk that branches out significantly at various heights, creating a spreading canopy. Apical dominance refers to the phenomenon where the main central stem of the plant grows more prominently than the side stems, which can lead to a more branched appearance, rather than a single trunk like that of the palm tree. Excurrent branching describes a growth form where a main leader dominates the canopy, but it still includes some branching that is more pronounced than in columnar forms. Thus, columnar accurately captures the characteristics of palm trees and their unique growth habit.