Acrostichum aureum

Pteridaceae

Acrostichum aureum L.

Link to Australian Plant Name Index for publication details and synonyms: https://id.biodiversity.org.au/name/apni/74258

Terrestrial ferns of moist ground, often on muddy ±saline substrates. Rhizome stout, creeping to erect, with large scales to c. 40 mm long and thick fleshy prop roots. Fronds to c. 3–4 m tall. Stipe up to one-third length of frond, scaly at base. Lamina dull green to golden green, 1-pinnate (simple in juvenile fronds), stiff, coriaceous, glabrous. Pinnae numerous, ascending, narrowly oblong to lanceolate, conspicuously stalked (except perhaps the uppermost ones); upper pinnae smaller and fertile; sterile pinnae c. 35 cm long, c. 4–5 cm wide; apex rounded to truncate, usually with a short abrupt point; lowermost pinnae sometimes reduced; all pinna margins entire. Secondary veins none; tertiary veins forming a close network of oblique (except for the costal ones) elongate-hexagonal meshes without free included veinlets. Sporangia covering lower surface of fertile pinnae, or only in the apical part; paraphyses abundant, filiform, several-celled with dark end-cells. Spores tetrahedral.

Pantropical. In Australia known from near Darwin, NT, and NE QLD between Cape York and Cardwell.

Terrestrial, usually in the supra-littoral zone on the fringes of riparian and swamp mangrove forest, paperbark swamp forest or the border between mangrove and vine forest.

One of few ferns that grow in salt affected areas.

An easy to cultivate fern if placed in bright moist situations in the garden in tropical and subtropical areas. This fern can also be grown in a container in a moisture retentive terrestrial mix. It commonly germinates from spore around the garden, especially in salt affected areas, and may be invasive in some situations.

Acrostichum aureum can be distinguished by having broader pinnae (40–50 mm wide) and longer rhizome scales (c. 40 mm long) from Acrostichum speciosum which has narrower pinnae (< 35 mm wide) and shorter rhizome scales (< 10 mm long).