Prionium serratum (Palmiet) is an endemic South African, semi-aquatic, evergreen plant forming dense, 2m-high shrublands along riverbanks in the Western Cape to KwaZulu-Natal. It features tough, saw-toothed, pale green leaves and dark, fibrous stems. Crucial for riverine ecosystem rehabilitation, it stabilizes banks, slows water flow, and filters water. 
Key Details of Prionium serratum:
Habitat: It thrives in shallow, fast-flowing water, often dominating stream corridors.
Structure: It is a rhizomatous shrub, with stems 50-100 mm in diameter, covered in the fibrous, black, or dark brown remnants of old leaves.
Leaves: Leaves are stiff, leathery, sword-shaped, and strongly serrated along the margins.
Flowers: Small, brownish flowers are borne on large (up to 500 mm), branched panicles, typically blooming from September to February.
Ecological Role: Palmiet wetlands are vital for water purification, carbon storage (trapping 
 in peat) and preventing soil erosion during floods.
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