1. A type of vascular cylinder in plant stems in which the vascular bundles are arranged in a ring around a central pith, characteristic of most dicots and some monocots.
Usage: botany; technical

Examples

• The eustele structure allows for secondary growth in woody plants.
• In a cross-section of a dicot stem, the eustele arrangement is clearly visible.
• The eustele differs from other stele types in its organized ring of vascular bundles.
• Botanists identify the eustele by examining the distribution of xylem and phloem tissues.