Poaceae

Hymenachne amplexicaulis and hybrids

Common Names: Hymenachne Synonyms: Hymenachne amplexicaulis

Plant Form: Tall perennial semi-aquatic grass. Size: Up to 2.5 m tall. Stem: Upright or semi-upright, relatively robust, hairless. Filled with a light pith that helps flotation. Leaves: Elongated blades 10-45 cm long, clasping around stem, with pointed tips. Mostly hairless except sometimes towards base. Small membranous flap at join (ligule). Flowers: Dense, long 10-50 cm flower spike with large number of spikelets. Fruit and Seeds: Small oval shaped seeds which remain enclosed in bracts when they fall. Habitat: Swamps, wetlands, riverbanks. Distinguishing Features: Stem-clasping leaf bases distinguish from native Hymenachne species. Impacts: Blocks and chokes waterways, reduces habitat for native fauna, reduces sugarcane quality significantly.