hollow stems

Hollow stems are plant stems with empty or air-filled centers rather than solid tissue.

Many grasses, bamboos, and herbaceous plants have this structure, which provides strength while minimizing weight—an efficient engineering solution that allows tall plants to stand upright without excessive material.

In botanical and gardening contexts, hollow stems help identify plant families and can affect how cuttings are taken or how plants respond to pruning.

The hollow stems of the sedge made it easy to use as natural straws.