eustele
/ˈjuːstiːl/
noun
- A type of plant stem structure where the vascular tissue is arranged in a ring of separate bundles around a central pith, typical of many ferns and seed plants.
- The eustele of a sunflower stem is easy to see under a microscope.
- Botany students learn to identify a eustele in cross-sections of plant stems.
- Unlike a protostele, a eustele has distinct vascular bundles.