Carex helferi

The sedge has a woody rhizome with central culms that have a triangular cross-section with a length of 20 to 50 cm (7.9 to 19.7 in) and a width of 1 to 3 mm (0.039 to 0.118 in) and that are smooth lower down with a rough texture toward the top. It has basal flattish to folded lengthwise leaves with a broadly linear to lanceolate shaped blade that is 17 to 60 cm (6.7 to 23.6 in) long with a 1 to 7 cm (0.39 to 2.76 in) long dark brown sheaths that usually disintegrate. The narrow inflorescences appear as a narrow branched cluster with a length of 17 to 20 cm (6.7 to 7.9 in) with three to six crowded to distant nodes.[2]

The species was first formally described by the botanist Johann Otto Boeckeler in 1876 as a part of the work Linnaea.[3] It has two synonyms;

• Carex helferi subsp. mapaniifolia (Ridl.) T.Koyama
• Carex mapaniifolia Ridl. [2]

It is often situated along river banks in the understorey of evergreen forests from an altitude of 0 to 400 m (0 to 1,312 ft)[2] in tropical biomes, the range of the plant extends from Myanmar in the north to Thailand in the south and on the island of Java in Indonesia.[1]

• List of Carex species