Asplenium australasicum

Aspleniaceae

Asplenium australasicum (J.Sm.) Hook.

Link to Australian Plant Name Index for publication details and synonyms: https://id.biodiversity.org.au/name/apni/105150

Birds-Nest Fern

Ferns with nest-like habit. Rhizome erect, scaly, unbranched with a single growing point. Fronds ±straight, arising in a regular rosette at a small angle to vertical. Stipe indistinct, 1–3 cm long, 6–15 mm wide. Rachis in cross-section flat on upper surface, strongly keeled below. Lamina narrowly obovate, simple, 50–175 cm long, 6–19 cm wide, shiny green, ±glabrous; bases narrowly cuneate; margins entire; apices acute or obtuse; veins free except for a marginal connection. Sori very numerous, close together; longest 16–60 mm long, extending from midrib, usually occupying more than half the width of the lamina. Perispores pale with fimbriate broad ridges and fenestrate lacunae; exospores 44.1–47.9 × 27.6–32.8 µm (means). 

Occurs on the east coast from the McIllwraith Range CYP through Wet Tropics of NE QLD to south-eastern NSW. Also Lord Howe and Norfolk Island. Also Malesia and Pacific Islands.

Epiphytic or lithophytic in rainforest and wet sclerophyll forest. In the higher altitude rainforests of NE QLD it is an abundant canopy and subcanopy epiphyte.

This is a large nest-forming species with a rosette of fronds that funnel rain and falling debris into its root system. It is widely cultivated and many horticultural forms exist.

This is a commonly cultivated ornamental fern. It grows well in a greenhouse or semi-shaded garden situation either on a tree, in a hanging basket or pot or in the ground. When grown in a container it should be planted in a coarse free draining epiphyte mix. A mature plant requires a large container for stability.

1a. Midrib strongly keeled on lower surface = Asplenium australasicum

1b. Midrib rounded on lower surface = Asplenium nidus