Pith The spongelike substance in the center of a stem. This feature helps describe plant support, storage, water movement, or vegetative spread.
Glossary: Stem / root structures
Purdue Arboretum botanical terminology reference and learning database.
Stem / root structures
Prickle A sharp outgrowth of the epidermis or bark, different from a thorn or spine. Did you know? Rose “thorns” are prickles, which arise from the outer stem tissue rather than being modified branches.
Procumbent Trailing or lying flat on the ground, but not rooting
Pseudobulb A thickened above-ground modified stem of some orchids. This feature helps describe plant support, storage, water movement, or vegetative spread. Did you know? Orchid pseudobulbs store water and nutrients, helping the plant survive dry periods between rains.