Commonly called ’bamboo’ in SA, this perennial grass to 4 metres tall looks like similar to Phragmites reed, only bigger. The stems are woody like bamboo, with leaves in two ranks along most of their length. The flowering heads are dense white plumes at top of stems, but never produce seed. There are also forms with green/yellow striped leaves. Once planted, giant reed is persistent. It can be spread into native vegetation along streams by waste dumping, and floods can move it downstream into wetlands.
(Note: NB Arundo donax declaration is pending approval by NRM Boards and Minister)