Which type of tree growth form typically has a wide spread?

The type of tree growth form that typically has a wide spread is the spreading growth form. Trees with this growth form are characterized by their branches extending outward from the trunk in a broad manner, creating a wide canopy. This adaptation allows for greater light capture from the sides, which is particularly beneficial in densely populated forest areas where competition for sunlight is fierce.

Spreading trees often display a low and broad habit, which not only supports increased photosynthetic efficiency but also stabilizes the tree by distributing weight across a larger area. This can be advantageous in terms of resilience against wind and environmental stressors.

In contrast, the other growth forms—horizontal, upright, and vertical—relate more to the orientation or verticality of the tree. Horizontal may imply a sweeping branching pattern but not necessarily a wide spread, upright suggests a more narrow, tall growth without significant lateral expansion, and vertical focuses on height rather than the breadth of growth. Thus, the spreading growth form distinctly emphasizes wide lateral expansion, making it the correct choice in this context.