Caulescence

Caulescence is a plant growth form characterized by the development of an above-ground stem as the main axis supporting foliage. In caulescent taxa, leaves are borne along the stem, with nodes and internodes often present, and the stem may be herbaceous or woody. This habit is described as the opposite of acaulescence, in which plants have little to no obvious stem and leaves arise in a basal rosette or are otherwise clustered at ground level.

The term derives from Latin caulus, meaning stem, with the suffix -escence indicating a state or condition. It is used primarily in floras, morphological descriptions, and horticulture to describe habit, rather than to define a taxon.

Variation within caulescent forms can be broad: some plants have a short stem that barely elevates leaves, while others have a prominent, branching stem. Leaves may be sessile or petiolate, and the degree of branching can vary with species and environment. In some cases, plants may be acaulescent under certain conditions and caulescent under others, such as during flowering or in response to light and space.

The designation is most commonly applied to herbaceous or semi-woody plants, and serves to distinguish those with a distinct above-ground axis from those with a minimal stem or a rosette of leaves at ground level. It is one of several growth-form descriptors used in plant descriptions and taxonomy.